Mechanical Systems_Rachana Bhandarkar

Cooling Strategies - Assignment 01

MECHANICAL SYSTEMS PORTFOLIO Rachana Bhandarkar | NU17UAR020 | B.Arch Sem 8 |15BAR 8.6 | Nitte institute of Architecture Instructor : Shoumik Desai

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Mechanical Systems Portfolio | Spring 2021 | Rachana Bhandarkar

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CONTENTS

Cooling Strategies - Assignment 01

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01

Cooling Strategies

02

Single Line Diagrams

03

Single Line Diagrams

04

Elevators and Escalators

05

Viva Questions

Active strategies that can be implemented in a school building

Single line diagrams of 5 active strategies

Single line diagrams of 2 active strategies

Working mechanisms of elevators and escalators

A questionnaire for student reference

Mechanical Systems Portfolio | Spring 2021 | Rachana Bhandarkar

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Cooling Strategies - Assignment 01

Assignment

01

Time problem dealing with the active strategies that can be implemented in a school building to be designed in the hot and humid weather of Mangalore Expected Outcome : Three active strategies to be implemented after understanding the climate of the place with the help of psychrometric charts and PMV graphs.

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Cooling Strategies - Assignment 01

Site And Climate Analysis Location :

Mangalore, India

Site Area

:

36m x 18m = 648 sq. m

Climate :

Warm and Humid Temperature : 27 - 34 degree celsius Annual Rainfall : 3500mm

Building Typology

:

Institutional - School

Spaces

:

• Classrooms • Administrative Block • Gathering Space

Graph showing the Realtive humidity percentage in Mangalore throughout the year

Graph showing the Average temperature in Mangalore throughout the year

Graph showing the Annual Rainfall in Mangalore throughout the year

Winter

Summer

Monsoon

Through the above chart we can deduce that Mangalore is divided into 3 seasons - Summer, Winter and Monsoon.

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Cooling Strategies - Assignment 01

A N A LY S I S Strategy Analysis

- WINTER

A N A LY S I S - S U M M E R

F r o m t h e a bthat o v e c h aduring r t w e c a n i d winters e n t i f y t h a t d ur i nequally g t h e w i n t e r susing - e q u a l l Natural y using From the above chart we can identfy Ventilation, Mass Cooling N a t u r a l Ve n t i l a t i o n , M a s s C o o l i n g a n d A i r- C o n d i t i o n i n g a n d D e h u m i d i f i c a t i o n strategies can help achieve comfort zone within a building. and Air - Conditioning and Dehumidification strategies can help acheive comfort zone within a building.

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From the above chart we can identify that during the summer - equally using From the above chart we can that N a t u ridentfy a l Ve n t i l a t i o n , M a s s during C o o l i n g a n dmonsoon A i r- C o n d i t i o n i n g-ausing n d D e h u mmore i d i f i c a t i o nNatural Ventilation and strategies can help achieve comfort zone within a building.

Air - Conditioning and Dehumidification and a moderate amount of Mass Cooling strategies can help 30/03/2021 Mechanical Systems | Spring Semester 2021 | Group 6 acheive comfort zone within a building.

A N A LY S I S - M O N S O O N

From the above chart we can equally Ventilation, Mass F r o m identfy t h e a b o v e c hthat a r t w e cduring a n i d e n t i f y twinters h a t d u r i n g t he m o n s o o n - u s iusing n g m o r e oNatural f N a t u r a l Ve n t i l a t i o n a n d A i r- C o n d i t i o n i n g a n d D e h u m i d i f i c a t i o n a n d a m o d e r a t e a m o u n t o f Mand a s s C o oDehumidification l i n g s t r a t e g i e s c a n h e l p a c h i e vstrategies e c o m f o r t z o n e wcan i t h i n ahelp b u i l d i n gacheive .

Cooling and Air - Conditioning comfort zone within a building.

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Cooling Strategies - Assignment 01

Strategy Analysis Months :

January - December

This shows us the hourly data points throughout the year and by using the Givoni Bioclimatic Chart we can identify the Low Energy cooling systems to moderate the human comfort in a building.

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Cooling Strategies - Assignment 01

Strategy Analysis Months :

PREDICTED MEAN VOTE - GRAPH

March - May

By adjusting the variables effecting the PMV we can identify a comfortable condition for thr occupant.

By the adjusted variables we can conclude that a neutral sensation with a PMV value of -0.01 is acheived in the given weather condition.

Inference:

From all the above charts it can be

By adjusting the variables effecting the PMV we can identify a comfortable condition for the occupant.

By the adjusted variables we can conclude that a neutral sensation with a PMV concluded that the problems temperatures v a l u e o f - that 0 . 0 1 have i s a c hto i e vbe e d dealt i n t h e with g i v e nare w e ahumidity t h e r c o n dand i t i o nhigh .

From the Psychometric chart the methods to be adopted are : 30/03/2021 Mechanical - Provision of Natural Ventillation - Mass cooling 30/04/2021

Systems | Spring Semester 2021 | Group 6

Mechanical Systems Portfolio | Spring 2021 | Rachana Bhandarkar

while maintaining a steady temperature inside.

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Cooling Strategies - Assignment 01

Strategy 01

S T R ACrossT Ventilation E G Y: 1

NATURAL VENTILATION

Passive ventilation is the process of supplying air to and removing air from an indoor space without using mechanical systems.

It refers to the flow of external air to an indoor space as a result of pressure differences Passive ventilation arising from natural forces . ural Ven t i l a t i o n Nat :

The system relies on wind to force cool exterior air into the building through an inlet (like a wall louvre, a gable or an opening) while outlet forces warm interior air outside through a roof outlet (like a vent or an opening).

is the process of supplying air to and removing air from an indoor space without using mechanical systems.

It refers to the flow of external air to an indoor space as a result of pressure differences arising from natural forces.

Fac t o rs a f f ec t i n g

:

• • • • •

Dominant wind speed and direction Surrounding environment Building footprint and orientation Outdoor temperature and humidity Window sizing, location, and operable

T ype s o f i t

:

• •

C r o s s Ve n t i l a t i o n S t a c k Ve n t i l a t i o n

C r o s s Ven t i l a t i o n Factors : Affecting

Stack effect or chimney effect is the movement of air into and The system relies on wind to force cool exterior air into the out of buildings, chimneys, flue-gas stacks, or other containers, b u i l d i nWind g t h Speed rough an inlet (like a wall louvre, a gable, or an open • Dominant Stack Ventilation :r o m a i r b u o y a n c y . r e s u l t i n g f w i n d o w ) w h i l e o u t l e t f o r c e s w a r m i n t e r i o r a i r o u t s i d e ( t h r o u g h a • Surrounding Environment Stack effect or chimney effect is the movement of air into and out of the building, chimneys, flue r o o f v e n t o r h i g h e r w i n d o w o p e n i n g ) .

B u o y a n c y o c c u r s d u e t o a d i f f e r e n c e i n i n d o o r- t o - o u t d o o r a i r • Building footprint and orientation gas stacks or other containers resulting from air buoyancy. density resulting from temperature and moisture differences.

• Outdoor temperature and humidity • Window sizing, location and operation

Types

:

S t a ck Ve n ti l a ti o n

Image Source: Kwok,The Green Studio Handbook, p. 140.

Buoyancy occurs due to difference in indoor to outdoor air density resulting from temperature and moisture differences.

• Cross Ventilation • Stack Ventilation

Stack Ventilation. [Image](n.d). Retrieved from

30/03/2021 30/04/2021 Importance of cross ventilation. [Image] (2015). Retrieved from

M e c h a n i c a l S y s t e m s | S p r i n g S e m e s t e r 2 0 2 1 | G r o uhttps://www.passivent.com/night-cooling p 6 Mechanical Systems Portfolio | Spring 2021 | Rachana Bhandarkar

https://indiansustainability.wordpress.com/2015/08/04/importance-of-cross-ventilation/

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STRATEGY 2

Cooling Strategies - Assignment 01

Strategy 02 Mass Cooling

MASS COOLING

Radiant Cooling

:

:

‘Thermal mass’ describes a material’s capacity to abs water and concrete have a high capacity to store hea mass’ materials.

A radiant cooling system is a temperature-controlled surface that cools indoor temperatures One of the ways to achieve this is the installation of by removing sensible heat and where more than half of e n vheat e l o p . transfer occurs through thermal radiation. radiant cooling system is a temperature-controlled Raobjects, d i a n t Coccupants, o o l i n g equipment : andAblights Heat will flow from y r e m oin v i na g space s e n s i b l etoh eaa cooled t a n d w hsurface e r e m o r e as than half r a d i a t i o n . long as their temperatures are warmer than that of theHcooled surface and they are within the eat will flow from objects, occupants, equipment an line of sight of the cooled surface. long as their temperatures are warmer than that of th

Thermal mass describes a materials capacity to absorb, store and release heat. For example water and concrete have high capacity to store heat and is referred to as high internal thermal mass materials.

line of sight of the cooled surface.

STRATEGY 2 M a s s C o o l in g

:

‘Thermal mass’ describes a material’s capacity to absorb, store and release heat. For example water and concrete have a high capacity to store heat and are referred to as ‘high thermal mass’ materials.

One of the ways to achieve this is the installation of Radiant Cooling systems on the building envelop.

R a d i a n t C o o l in g

Factors : Affecting

• • • • •

Type of cooling medium Surface area Thermal Conductivity Difference in temperatures Size of the home

:

A radiant cooling system is a temperature-controlled surface that cools indoor temperatures by removing sensible heat and where more than half of heat transfer occurs through thermal radiation.

Heat will flow from objects, occupants, equipment and lights in a space to a cooled surface as long as their temperatures are warmer than that of the cooled surface and they are within the line of sight of the cooled surface.

Radiant cooling and heating involves piping chilled water or hot water through a material th space. This method is most commonly extended to chilled sails, in-floor radiant slab, radia Piping water through these materials requires significantly less transport energy than mov creates sustained and predictable savings on monthly energy

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Radiant cooling and heating involves piping chilled water or hot water through a material that can transfer heat effectively in the space. This method is most commonly extended to chilled sails, in-floor radiant slab, radiant ceiling panels, and radiant walls.

P i p i n g w a t e r t h r o u g h t h e s e m a t e r i a l s r e q u i r e s Radiant s i g n i f i c a ncooling t l y l e s s tand r a n s pheating o r t e n e r ginvolves y t h a n m opiping v i n g a i rchilled w i t h a water f o r c e d - or a i r hot s y s t ewater m . T h i sthrough a material that c r e a t e s s u s t a i n ecan d a n dtransfer p r e d i c t a heat b l e s a effectively v i n g s o n m o nin t h the l y e nspace. e r g y b i l This ls. method is most commonly extended to chilled 30/03/2021

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Thermal mass. [Image] (2013). Retrieved from https://www.yourhome.gov.au/passive-design/thermal-mass

sails, in floor radiant slab, radiant cieling panels, and radiant walls. Piping water through these Mechanical Systems | Spring Semester 2021 | Group 6 materials requires significantly less transport energy than moving air with a9 force - air system.

This created sustained and predictable savings on monthly energy bills.

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STRATEGY 3

Dehumidifier air conditioning allows the humid air to pass through cool coils and evaporate and returns it back to the room a n d t h e r e s u l t i s c o o l e r a i r. M o r e o f t e n t h a n n o t i t i s t h e h u m i d air and not heat itself which is the cause of discomfort in warm places.

Cooling Strategies - Assignment 01

Strategy 03 AIR CONDITIONING AND DE - HUMIDIFICATION

Stand Alone AC

:

Airnconditioning the humidity of the air In stand alone AC’s device d itio i n g a nisdthe process of removing heat and controlling Yo uboth h a coils v e t are w o inside s e t s one of m e t a l which c o i l sis ; usually t h e f i rlocated s t o n einside c o l l ethe c t house s t h e or heat fr : T ymaybe p e s acheived o f A i rusing within a building to acheive more comfortable environment. This the building. : second one disperses the heat outside. d i f i cpowered a t i odevices n (air conditioners) or by passive cooling or ventilative cooling.

The key part here is the refrigerant; this is a liquid mixture that t Conditioning Systems two sets of coils.

o n i n g i s t h e p r o c e s s o f r e m o v i n g h e a t a n d c oS n ttraonl ldi n-gA l o n e A C U n i t s : t y o f t h e a i r w i t h i n a b u i l d i n g t o a c h i e v e a m Ionr es t a n d - a l o n e A C u n i t s , b o t h c o i l s a r e inside one device (usually located inside e interior environment. e a c h i e v e d u s i n g p o w e r e d d e v i c e s ( ‘ a i r c o n d i tt hi oe nheoruss’ e) ), . cooling or by ventilative cooling.

Split-System AC Units :

e r a i r c o n d i t i o n i n g a l l o w s t h e h u m i d a i r t o p aS sp sl i t - s y s t e m a i r c o n d i t i o n e r s a r e o l c o i l s a n d e v a p o r a t e a n d r e t u r n s i t b a c k t o ctohme prr oi soe m d of two shells. u l t i s c o o l e r a i r. M o r e o f t e n t h a n n o t i t i s t h e h u m i d h e a t i t s e l f w h i c h i s t h e c a u s e o f d i s c o m f o r t Ti nh awt amrema n s t h a t t h e c o o l i n g c o i l i s

inside your house and the heating coil that dispenses heat and compressor are outside your house.

Stand-Alone AC Units SplitDehumidifier air conditioning allows the humid Yo uairhtoapass v e through t w o s cool e t scoil o fand mevaporate e t a l c o i l s ; t h e f i Split r s t oAC n e c o l l e c t s :t h e h e a t f r o m y o u r h o u s e a n d t h e and returns it back to the room and the result often than not it is the s e cisocooler n d oair. n eMore 3d0i /s0p3e/ 2r 0s 2e 1s t h e h e a t o u t s i d e . Split Air Conditioners M e c husually a n i c aconsists l S y s t eof mtwo s | Sshells. pring Semester 2021 | Group 6 humid air and not heat itself which is the cause of discomfort in warm places.

That means the cooling coil is located inside the T h e k e y p a r t h e r e i s t h e r e f r i g e r a n t ; t h i s i s a l i q u i d m i x t u r e t h a t t r a n s f ehouse r s h eand a t the b eheating t w e e ncoilt hthat e dispenses and compressor are located outside the house. two sets of coils.

f Ai r o ni ng S y s t em s

:

• Humidity l o neFactors AC U n: its :

o n e AAffecting C u n i t s , b o t• h cClothing o i l s aand r e Insulation d e v i c e ( u s u a l l y l o• c aMetabolic t e d i n sRate ide • Air temperature • Air velocity

s t em A C U nits :

m a i r Types c o n d i t i o n: e r • s aStand r e alone AC • Split AC units of two shells.

s that the cooling coil is house and the heating coil nses heat and compressor are ur house.

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Mechanical Systems Portfolio | Spring 2021 | Rachana Bhandarkar Stand-A lone AC Units

Split-System AC Units

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CoolingLine Single Strategies Diagrams - Assignment - Assignment 01 2

Assignment

02

To understand the working mechanism and components of 5 active cooling methods by means of a single line diagram.

Expected Outcome : Single line diagram of the chosen active cooling strategy along with the details of its working components.

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CoolingLine Single Strategies Diagrams - Assignment - Assignment 01 2

Split Air conditioner

Components of AC

About AC

Refrigerant : Refrigerants are usually liquids with very low boiling points which are used to carry heat from the inside of a building to the outside.

:

Split air conditioners are one of the most common active cooling system used in residential, commercial and industrial sectors. An added advantage of this system is that, energy wise this system has the highest energy star rating which helps in increasing energy efficiency. Split air conditioners are used in areas of Hot and dry and Warm and humid climate.

Cool Refrigerant

Compressor : A compressor is a device that pressurizes the refrigerant that results in a rise in temperature. This eventually makes the temperature of the refrigerant higher than the outside resulting in a flow of hot air in the outside direction.

Condensor Coil : The condenser coil is the outdoor unit that receives the high pressure, high-temperature refrigerant, which releases the heat to the outside with the help of the fans and cools down the Refrigerant into liquid again in this process.

Hot Refrigerant

Evaporator Coil

Cool Air

Fan

Fan

Condensor Coil

Compressor

Evaporator Coil : Mainly used to reduce the pressure of the refrigerant, which makes it dissipate heat and reduce to a temperature much lower than the surrounding temperature with the help of the fans.

Expansion Valve Cold Refrigerant

Working

Warm Air

Expansion Valve : When the refrigerant leaves the condenser in its liquid form, it’s still too hot to enter the evaporator coil, the expansion valve reduces the pressure of the refrigerant thus leading to the temperature drop and converts it into gas.

Warm Refrigerant

:

The return vents, located inside the home, suck in hot air from inside the room. The refrigerant picks up heat as air flows over the evaporator coils, which are very cold.

Fan : Used to speed up the cooling process.

Psychrometric Chart

:

Once the refrigerant absorbs a certain amount of heat from the indoor air, it then discharges it to the compressor, which pressurizes and heats up the refrigerant. After passing through the compressor, it flows through the condenser coils. A big, often loud condenser fan helps to push air over the condenser coils to facilitate heat transfer outdoors.

The refrigerant then cycles back over an expansion valve, depressurizing it and cooling it down. It then performs the same heat absorption process over and over again.

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CoolingLine Single Strategies Diagrams - Assignment - Assignment 01 2

Radiant Wall Cooling RADIAN About

:

T WALL COOLING SYSTEM Components

Panels : In radiant panel type cooling, cooper tubes may be used for circulating chilled water

Radiant Cooling is based on the physical principle, that bodies with varying temperatures C o mp o nexchange e n t s thermal : radiation until an equilibrium is achieved.

Radiant cooling systems work by circulating chilled water through a network of polymer pipes installed in floors, walls or ceilings. This network of pipes can turn the floors, walls and ceilings of a conditioned space into cooled surfaces that evenly absorb heat energy

Piping : Loops of cross-linked polyethylene pipes are embedded in walls/ floors/ ceilings and chilled water passed through them.

Chiller : A chiller is used to cool the fluid medium to required temperatures Other components : Other components like manifolds, valves, pumps, etc. complete the layout.

Panels In radiant panel type cooling, cooper tubes may be used for circulating chilled water

Wo r k i n g

Piping Loops of cross-linked polyethylene pipes are embedded in walls/ floors/ ceilings and chilled water passed through them.

Chiller A chiller is used to cool the fluid medium to required temperatures.

:

Radiant cooling is the use of cooled surfaces to remove sensible heat by radiation and convection.

As in radiant cooling system, the thermal radiation due to wall, lamp, ceiling, and electronic components like laptop is absorbed by the chilled water which is passing through the pipes like copper/ polyethylene tubes embedded in the walls or use of the panels on the ceiling and walls.

Working : of chilled water result to cool the room temperature at desired This continues flow Radiant temperature. cooling is the In use ofmanner cooled surfaces to remove sensible heat by this radiant cooling system is works. radiation and convection.

As in radiant cooling system, the thermal radiation due to wall, lamp, ceiling, and electronic components like laptop is absorbed by the chilled water which is passing through the pipes like copper/ polyethylene tubes embedded in the walls or use of the panels on the ceiling and walls.

This continues flow of chilled water result to cool the room temperature at desired temperature. In this manner radiant cooling system is works.

Other components Other components like manifolds, valves, pumps, etc. complete the layout.

P s y c hom etric : Char t Psychrometric Chart

:

1 - 2 Cooling and Dehumidification of air in outdoor air cooling system

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M e c h aMechanical n i c a l SSystems y s t e mPortfolio s | S p| rSpring i n g 2021 S e m| eRachana s t e r Bhandarkar 2021 | Group 6

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E V A P O R A T I V E C OE O LVIAN P G OS R Y SATTE IMV

E COOLING

CoolingLine Single Strategies Diagrams - Assignment - Assignment 01 2

Evaporative Cooling Ab o u t About

::

Components

Evaporative cooling is a process that uses the effect of evaporation as a natural heat sink. Sensible heat from the air is absorbed to be used as latent Water Tank heat necessary to evaporate water. The amount of sensible heat absorbed depends on the amount of water that can be evaporated.

C o m po n en t s

:

:

Evaporative cooling is a process that uses the effect of evaporation as a To store the water needed to fulfil the process requirements Evaporative cooling can be direct or indirect; passive or hybrid. In direct evaporative cooling, the water content of the cooled air increases because air natural heat sink. Sensible heat from the air is absorbed to be used as is in contact with the evaporated water. In indirect evaporative cooling, evaporation occurs inside a heatValve exchanger and the water content of the cooled Float : latent heat necessary to evaporate TheSince amount of sensible air remainswater. unchanged. high evaporation ratesheat might increase relative humidity and create discomfort, direct evaporative cooling can be applied To keep the water level in check: prevent tank overflow only in places where relative humidity is very low. absorbed depends on the amount of water that can be evaporated.

Climateor zone - Hot andpassive dry Evaporative indirect; or hybrid. In direct : be direct Ap p l i ca tcooling i o n can Air Blower : evaporative cooling, the water content of the cooled air increases because Building types - The unit is especially applicable for public places, like workshop, internet bar, sports room,cool theatre, room and so on,spaces it is also To blow airmeeting into the occupied air is in contact with the evaporated Inand indirect applicablewater. for hotel villa. evaporative cooling, evaporation occurs inside a heat exchanger and the water content of Louvers : the cooled air remains unchanged.

Since high evaporation rates might : Si n gl e L i n e Wo r k i n g : It allows air to pass through it keeping away unwanted elements like water, dirt etc increase relative humidity and create discomfort, direct evaporative Diagr a m Two-stage evaporative cooling, also known as indirect/direct adiabatic cooling, makes use of cooling can be applied only in places where relative humidity is very low. both techniques described above to cool Filters the air. : They are used to filter out foreign particulate matter in air to ensure acceptable air quality The first indirect adiabatic “cooling step” uses cold recirculation water in a heat exchanger to pre-cool the ambient air. Because no moisture is added, the air reaches a lower dry bulb and wet bulb temperature than the outside air, when leaving the heat exchanger.

W a t e r Ta n k Float Valve Thestore second “cooling step” coolsTo thekeep air even furtherlevel through the wet pads.

To thedirect wateradiabatic needed to fulfil the the water in check: prevent As a result of this two-step cooling process, the air can be brought down to a much lower process requirements tank overflow temperature, while the increase in moisture is significantly lower.

P sych o met r i c : Chart

Working

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Psychrometric Chart

Louvres It allows air to pass thro away unwanted element etc.

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Mechanical Systems | Spring Semester 2021 | Group 6

Two-stage evaporative cooling, also known as indirect/direct adiabatic cooling, makes use of both techniques described above to cool the air.

The first indirect adiabatic “cooling step” uses cold recirculation water in a heat exchanger to pre-cool the ambient air. Because no moisture is added, the air reaches a lower dry bulb and wet bulb temperature 1 - 2 than the outside air, when leaving the heat exchanger. The second direct Indirect Evaporative Cooling adiabatic “cooling step” cools the air even further through the wet pads.

2 - 3 As a result of this two-step cooling process, the air can be brought Direct Evaporative Cooling down to a much lower temperature, while the increase in moisture is significantly lower.

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Air Blower To blow cool air into the occupied spaces

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CoolingLine Single Strategies Diagrams - Assignment - Assignment 01 2

Variable Refrigerant Volume

Components

About

Outdoor Units : Inside these units, condensation takes place. The refrigerant that goes into these units is in gaseous form as it would have absorbed heat from the indoors and would be released outside. When the refrigerant passes out of this unit it is in liquid for.

:

This type of system is suitable for warm and humid climates.

R I ATheBmost L Eefficient R way E Fof using R I this G system ERA N beT in buildings V O Lwith UME would different zones like hotels, office buildings or domestic buildings.

on

:

This type of system is suitable for warm and humid climates.

Indoor Units : They receive the refrigerant in liquid form, which is at a lower temperature. These indoor units absorb the heat from the room, which causes the refrigerant to evaporate and turns into vapour.

Hence the indoor units are also referred to as evaporators.

The most efficient way of using this system would be in buildings with different zones like hotels, office buildings or domestic buildings.

e

:

V A R I A B L E R E F R I G E R :A N T V O L U M E Comp on en ts

:

Refrigerant Piping The refrigerant travels in these pipes from the outdoor units to indoor units and vice versa. It transforms from gaseous into a liquid state during this process and keeps repeating.

The main components of a VRV system are outdoor systems, indoor units, and other accessories like refrigerant piping and wiring between the different components.

Outdoor Units Inside these units, condensation takes place. The refrigerant that goes into these units is in gaseous form as it would have absorbed heat from the indoors and would be released outside. When the refrigerant passes out of this unit it is in liquid for.

Psycho m etric : Char t Psychrometric Chart

:

V a r i a b l e R e f r i g e r a n t Vo l u m e

Mechanical Systems | Spring Semester 2021 | Group 6

Working

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Indoor Units

Two-stage evaporative cooling, also known as indirect/direct adiabatic They receive the refrigerant in liquid form, which is at a lower temperature.

These indoor units cooling, makes use of both techniques described above to cool the air. absorb the heat from the room, which causes the The first indirect adiabatic “cooling step” uses cold recirculation water refrigerant to evaporate and turns into vapour.

Hence the indoor units are also referred to as in a heat exchanger to pre-cool the ambient air. Because no moisture evaporators. is added, the air reaches a lower dry bulb and wet bulb temperature than the outside air, when leaving the heat exchanger. The second direct adiabatic “cooling step” cools the air even further through the wet pads.

As a result of this two-step cooling process, the air can be brought down to a much lower temperature, while the increase in moisture is significantly lower.

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Refrigerant Piping Mechanical Systems Portfolio | Spring 2021 | Rachana Bhandarkar The refrigerant travels in these pipes from the outdoor units to indoor units and vice versa. It transforms from gaseous into a liquid state during

1 - 2 Cooling and dehumidification in Split Air Conditioning System

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CoolingLine Single Strategies Diagrams - Assignment - Assignment 01 2

Economizer About

:

An economizer is a part of a building’s cooling system that uses cool outdoor air to cool the building instead of operating the air conditioning compressor.

An economizer is an add-on feature to an HVAC air handler that draws in outdoor air and mixes it with return air from indoors.Buildings in extremely hot, humid areas may not be suitable for adding an economizer

Working

:

An economizer is a part of a building’s cooling system that uses cool outdoor air to cool the building instead of operating the air conditioning compressor.

- An economizer is an add-on feature to an HVAC air handler that draws in outdoor air and mixes it with return air from indoors.

- A controller in the economizer measures the temperature and humidity of the outdoor air. When the outdoor temperature is favorable, the control switches the air conditioning compressor off and cools the building with outdoor air instead.

- The outdoor air got in controlled by the damper and mostly is at its 100% flow - The filter located, filters the air and sends the clean air to the mixing chamber.

- Where in mixing chamber the outdoor air and the indoor air is mixed enough in order to meet the thermostat setpoint without using the compressor.

- The excess return air is sent out through relief air outlet - The mixed air is then sent through cooling coil and to the room in order to meet the thermostat setpoint without using the compressor.

Components Dampers : Filter cleans the air by removing solid airborne particles Heating Coil : Heating coil raises the air temperature to the required supply temperature Cooling Coil : Cooling coil provides cooling and dehumidification. A thermostat and a controller are used to control both the heating and cooling coil.

Filter : A damper is a component that controls the airflow. This can be controlled manually. It automatically shuts down on power failure. It also prevents small birds or animals from entering.

Fan : Fan is used to draw air and to blow air wherever required.

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CoolingLine Single Strategies Diagrams - Assignment - Assignment 01 3

Assignment

03

To understand the working mechanism and components of two active cooling method by means of a single line diagram.

Expected Outcome : Single line diagram of the chosen active cooling strategies along with the details of its working components.

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ECONOMIZER CoolingLine Single Strategies Diagrams - Assignment - Assignment 01 3

About System 01

:

ECONOMIZER

An economizer is a part of a building’s cooling system that uses cool outdoor ECONOMIZER air to cool the building instead An economizer is a part of a building’s cooling system that uses cool outdoor air to cool of operating the air conditioning the building instead of operating the air conditioning compressor. compressor.

An economizer is an add-on feature to an HVAC air handler that draws in outdoor air An economizer is an add-on Abo utindoors. : and mixes it with return air feature from to an HVAC air handler that draws in economizer outdoor air and mixes it An with return air is a part of a building’s cooling system that uses cool outdoor from indoors. air to cool the building instead Formulae of operating the air conditioning Co-Efficient of Performance (COP) compressor.

An economizer is an add-on feature = Cooling Effect Work Inputto an HVAC air handler that draws in outdoor air and mixes it with return air = Heat Absorbed from indoors.

Heat rejected - Heat Absorbed Energy Efficiency Co-Efficient Ratio of Performance (COP) = Output Cooling Energy in BTU= Cooling Effect Work Input Input Electrical Energy in Wh = Heat Absorbed Seasonal Energy Efficiency Ratio Heat rejected - Heat Absorbed = Output Cooling Energy in BTU over a season Energy Efficiency Ratio = Output Input Electrical Energy in Wh over Cooling Energy in BTU the same season Input Electrical Energy in Wh

Seasonal Energy Efficiency Ratio Cooling Tower Formula M = (Ti -T0) X 100= Output Cooling Energy in BTU over a season (Ti -Twb) Input Electrical Energy in Wh over the same season Where, Ti = Inlet Temperature of water Cooling Tower Formula (0C/0F) T0 = Outlet Temperature of water M (0C/=0F)(Ti -T0) X 100 Twb = Wetbulb Temperature of air (0C/0F)(T -T ) i wb M = Cooling Tower Efficiency (%) Where, 17/04/2021 Mechanical Systems | Spring Semester 2021 | Group 6 Ti = Inlet Temperature of water 0 0 ( C/ F) T0 = Outlet Temperature of water (0C/0F) Twb = Wetbulb Temperature of air (0C/0F) M = Cooling Tower Efficiency (%) 17/04/2021 30/04/2021

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3

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CoolingLine Single Strategies Diagrams - Assignment - Assignment 01 3

System V 02 A

RIABLE REFRIGERANT VOLUME

VARIABLE REFRIGERANT VOLUME

Variable Refrigerant Volume (VRV) system is one of the Heating, Ventilation and Air Variable Refrigerant Volume (VRV) system is one of the Heating, Ventilation and Air Conditioning (HVAC) type in the building.

Conditioning (HVAC) A b o utype t in the building.: VRV system is a multi-split type air conditioner that uses variable refrigerant flow control VRV system is a multi-split type air conditioner that uses variable refrigerant flow control to provide customers with the ability to maintain individual to provide customers with the ability to maintain individual in floor eachofroom zone control inzone each control room and a building. and floor of a building.

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Cooling Strategies Elevators, escalators - Assignment and walkalators 01 - Assignment 4

Assignment

04

To understand the different types of elevators, escalators and walkalators and their mechanisms.

Expected Outcome : Details about the different types of escalators, elevators and walkalators and understand their working mechanisms and the different parts it consiste of. Also identifying the worlds fastest elevators and understanding their mechanism.

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Cooling Strategies Elevators, escalators - Assignment and walkalators 01 - Assignment 4

Elevators An elevator is a platform that could either be open or closed and is used for lifting or lowering both people and goods to upper and lower floors. In the past, it was not mandatory for story buildings to have elevators.

Gearless Elevators The type of elevators where the wheel is directly attached to the motor. They can move in speed upto 2000ft per minute.

TYPES OF ELEVATORS TRACTION : Elevator cars are pulled up by means of rolling steel ropes over a deeply grooved pulley.

They are further categorized into : Geared Elevators These types of lifts consists of a gear box along with a motor which drives the wheel that moves the ropes. They can move upto 500ft per minute. Used or mid and high rise buildings

Machine room less Elevators The type of elevators where the wheel is directly attached to the motor. They can move in speed upto 2000ft per minute.

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Cooling Strategies Elevators, escalators - Assignment and walkalators 01 - Assignment 4

COMPONENTS : An elevator is a platform that could either be open or closed and is used for lifting or lowering both people and goods to upper and lower floors. In the past, it was not mandatory for story buildings to have elevators.

Cabin : The part a lift unit designed for transportation of persons and/or goods.

Shaft : A space in which the lift cabin moves. The space is as a rule housed with pit bottom, walls and ceiling.

Machine Room : A room in which the drive unit (or units) and the connected equipment are situated, e.g. control elements.

Drive Unit : A unit that contains motor that drives a lift. In traction lifts it is so called traction machine and in hydraulic ones it is a set with a motor, pump and valve block.

T Guides : Rigid elements that secure guiding of a car frame and a cabin.

Car frame : A rigid construction that holds the car and travels in the guides.

Counterweight : A separately guided mass that partly counterbalances the cabin and secures ropes pressure to a driving pulley.

Controller : A unit that controls the lift travel.

Piston : A lift component that uses a working medium for a plane motion. The piston is composed of a cylinder and a ram. There are also single or multistage pistons so called telescopic.

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HYDRAULIC : These are powered by hydraulic piston within a cylinder. The movement of the piston happens by pumping hydraulic oil into the cylinder. The oil is controlled by an electric valve which enables the piston movement.

Car Guide Rails : The part of the lift that is responsible for the safe movement of the car and the counterweight.

Door Operators : Elevator door operator opens and closes the doors to an elevator at every level Car : The part a lift unit designed for transportation of persons and/or goods.

Lift well : This is rectangular in shape .RCC walls on 3 sides and the opening for lift shutters on the fourth side.

Travelling Cables : Elevator traveling cable is a link between the elevator car and controller and facilitates the movement of the car Piston : The piston separates the internal rod side from the internal cap side of the cylinder.

Controller : An elevator controller is a system that controls the elevators, the controller usually tunes down the voltage between 12V to 24V to the controlling system Valve Block : Hydraulic Valve Blocks, are machine parts that act as junctions between components in a hydraulic system that regulate flow of the fluid.

Pump : A hydraulic pump is a mechanical device that converts mechanical power into hydraulic energy.

Tank : The main function of a reservoir is to hold system hydraulic fluid in a convenient location for the pump inlet also the reservoir also holds excess fluid needed when the hydraulic system is in operation.

Cylinder : A hydraulic lift is a device for moving objects using force created by pressure on a liquid inside a cylinder that moves a piston upward.

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Cooling Strategies Elevators, escalators - Assignment and walkalators 01 - Assignment 4

PNEUMATIC : They are air-driven elevators that operate on laws of physics. It is constructed with polycarbonate and aluminum. This lift system is like a tube in a sealed vacuum. The air below and above the elevator car is what helps in the movement of the car.

Hoist Machine : It is a mechanical device used primarily for raising and lowering heavy loads but occasionally for moving objects horizontally.

Traction Cables : The part of the lift that is responsible for the safe movement of the car and the counterweight.

Door Openors : Elevator door operator opens and closes the doors to an elevator at every level Counterweights : A separately guided mass that partly counterbalances the cabin and secures ropes pressure to a driving pulley.

Oil Buffer : A buffer consisting of a cylinder and a piston or plunger where the oil in the cylinder acts as a medium to absorb and dissipate the kinetic energy of an impact, such as that of a descending elevator car or counterweight acting on the piston or plunger.

Pit : The elevator pit is the depression below the surface of the lowest landing that allows the elevator floor to be level with the floor of the lowest landing.

Motor Drive : A motor at the top of the shaft turns a pulley that raises and lowers cables attached to the cab and a counterweight.

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Cooling Strategies Elevators, escalators - Assignment and walkalators 01 - Assignment 4

PATERNOSTER : This type of lift is a passenger elevator which consists of a chain of open compartments (each usually designed for two persons) that move slowly in a loop up and down inside a building without stopping. Passengers can step on or off at any floor they like.

Car : The part a lift unit designed for transportation of persons and/or goods.

Sprocket Wheel : A sprocket-wheel or chainwheel is a profiled wheel with teeth, or cogs, that mesh with a chain, track or other perforated or indented material.

Flaps : A flap is a high-lift device used to reduce the stalling speed of an elevator at a given weight.

Travelling Cables : Elevator traveling cable is a link between the elevator car and controller and facilitates the movement of the car.

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Cooling Strategies Elevators, escalators - Assignment and walkalators 01 - Assignment 4

Fastest elevators CTF FINANCE TOWER Located in Guangzhou, China, the new CTF Finance Centre Tower not only is the world’s seventh tallest building, but is contains the world’s fastest elevator.

Standing at 530 metres (1,740ft), the lift in this incredible skyscraper can reach speeds up to 44mph.

TAIPEI 101 Speeding into second place is the Taipei 101, which can be found in Taiwan. This 1,670ft superstructure also held the title of fastest lift until 2016.The two lifts in the Taipei whizz up from ground to roof in 30 seconds at a speed of 37.7mph.

Type : Double Decker Lift Rated speed: Ascending speed-1260m/min; Descending speed- 600m/min Capacity: 1600kg, 21 persons Distance: 440.4m Stop floors: 1F,3F,4F,95F Production: Hitachi, ltd

Type : Cable less capsule lift Rated speed: Ascending speed-1010m/min; Descending speed- 600m/min Capacity: 1600kg, 24 persons Distance: 382.2m Service floors: 1F,5F,85F,86F,88F,89F(6floors) Production: Toshiba

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YOKOHAMA LANDMARK The famous Yokohama Landmark Tower in Yokohama, Japan, has a total of seventy-nine lifts.

The 296.3 metre (2,460ft) building also boasts a Mitsubishi lift which can travel 28mph this is the fastest lift in Japan.

Type : Electric lift Rated speed: Ascending speed-1010m/min; Descending speed- 749m/min Capacity: 1600kg, 24 persons Distance: 296.3m Production: Mitsubishi Electric

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Cooling Strategies Elevators, escalators - Assignment and walkalators 01 - Assignment 4

Escalators Escalators are essentially moving staircase but where people on them are expected to remain standing on one step whilst the step itself moves. For this reason, the rise are not governed by the same criteria as normal stairs.

CRISSCROSS Escalators going in one direction "stacked" with escalators going the opposite direction oriented adjacent but perpendicular, frequently used in department stores or shopping centers.

Types of Escalators : There are three basic configurations that are used for most common escalator systems: PARALLEL Up and down escalators adjacent or nearby, often seen in perpendicular areas,metro stations and multilevel movie theaters.

Side Elevation

Side Elevation

End Elevation

End Elevation

MULTIPLE Banks of more than one escalator going in the same direction parallel to banks going the other direction.

Side Elevation

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End Elevation

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COMPONENTS OF ESCALATOR Landing Platform : Landing platforms are the two platforms (at the two ends) that house the curved sections of the tracks, as well as the gears and motors that drive the stairs. The top platform usually contains the motor assembly and the main drive gear, while the bottom holds the return gear.

Truss : The truss is the hollow metal structure that bridges the lower and upper landings, composed of two side sections joined together with cross braces across the bottom and just below the top. The ends of the truss are attached to the top and bottom landing platforms via steel or concrete supports. It carries all the straight track sections connecting the upper and lower sections.

Balustrade : The balustrade is composed of handrails, balustrade panels, and skirt panels Handrail : The handrail provides a handhold for passengers while they are riding the escalator. The handrail is pulled along its own track by a chain that is connected to the main drive gear by a series of pulleys, keeping it at the same speed as the steps.

Tracks : The track system is built into the truss to guide the step chain, which continuously pulls the steps from the bottom platform and back to the top in an endless loop. One track guides the front wheels of the steps (called the step-wheel track) and another guides the back wheels of the steps (called the trailer-wheel track).

Steps : The steps themselves are solid, one piece, die-cast aluminium or steel. Yellow demarcation lines are sometimes added to indicate their edges. The steps are linked by a continuous metal chain that forms a closed loop. The front and back edges of the steps each have two wheels, the rear of which are set further apart and fit into the trailer-wheel track while the front set have narrower axles and fit the step-wheel track.

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Cooling Strategies - Assignment 01 - Assignment 4 Elevators, escalators and walkalators

Walkalators A moving walkway is a slow-moving conveyor mechanism that transports people across a horizontal or inclined plane over a short to medium distance. Moving walkways can be used by standing or walking on them. They are often installed in pairs, one for each direction.

Types of Escalators : There are two basic configurations that are used for most common walkalator systems:

PARALLEL A continuous series of flat metal plates join together to form a walkway – and are effectively identical to escalators in their construction. Most have a metal surface, though some models have a rubber surface for extra traction.The plates are one-piece, die-cast aluminium pallets, with a typical width between the walkway sides of 800–1,200 millimeters (31–47 inches). The walkway can be powered by an AC induction motor. Example speed is 0.5 metres per second (1.6 feet per second).

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MULTIPLE These are generally built with mesh metal belts or rubber walking surfaces over metal rollers. The walking surface may have a solid feel or a bouncy feel. Both types of moving walkway have a grooved surface to mesh with combplates at the ends.

Also, nearly all moving walkways are built with moving handrails similar to those on escalators.

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Cooling Viva Questions Strategies - Assignment - Assignment 5 01

Viva questions What is a psychrometric chart?

A psychrometric chart presents physical and thermal properties of moist air at a constant pressure in a graphical form.

What is adiabatic or evaporative cooling process?

It is a psychrometric process that involves the cooling of air without heat loss or gain. Sensible heat lost by the air is converted to latent heat in the added water vapor.

Why is the psychrometric chart used?

This can be useful in the design of heating, ventilation and air-conditioning systems for buildings, and psychrometric charts often include a zone in the middle that represents the range of conditions that people find comfortable under different circumstances.

What are the 4 stages of the Carnot cycle?

Stage 1- Isothermal expansion under heat input Stage 2- Adiabatic expansion accompanied by fall in temperature Stage 3- Isothermal compression Stage 4- Adiabatic compression accompanied by an increase in temperature

What are the different parameters in a psychrometric chart?

Dry bulb Degree Celsius/ Farhanheit or K Wet bulb Degree Celsius/ Farhanheit or K Relative humidity % Specific volume sq.m/kg d.a Dew point Degree Celsius/ Farhanheit Enthalpy kJ/kg d.a Humidity ratio g/kg d.a

What is COP? COP stands for Coefficient Of Performance and indicates the efficiency of heating and cooling machines. The COP is defined by the ratio heat dissipation and electrical power intake.

What is the formula for COP? COP= Cooling effect = Heat absorbed .

Work input Heat rejected- Heat absorbed

What is latent heat ?

It is the heat required to convert a solid into a liquid or vapour, or a liquid into a vapour, without change of temperature.

What is sensible heat ?

Sensible heat is the energy required to change the temperature of a substance with no phase change.

What is a sensible heating or cooling process?

It is a psychrometric process that involves the increase or decrease in the temperature of air without changing its humidity ratio.

What is the humidification process?

The process in which the moisture or water vapor or humidity is added to the air without changing its dry bulb (DB) temperature is called as humidification process What is the dehumidification process?

The process in which the moisture or water vapor or the humidity is removed from the air keeping its dry bulb (DB) temperature constant is called the dehumidification process.

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What are the 4 main refrigeration cycle components?

The compressor The condenser The expansion device The evaporator Explain the refrigeration process The refrigerant flows into the Compressor where it is compressed and pressurised. At this point, the refrigerant is a hot gas.

The refrigerant is then pushed to the Condenser which turns the vapour into liquid and absorbs some of the heat. The refrigerant then proceeds to the Expansion Valve where it expands, losing pressure and heat.

The refrigerant coming out of the expansion valve is cold and slow due to the loss of pressure.

It enters the Evaporator in a liquid state where the exchange of heat takes place thus cooling the load inside the refrigerator.

As the gas cools down the load, it absorbs the heat which turns it into a gas. The gas is then pushed back into the Compressor where it can start the cycle again.

What is EER? A room air conditioner’s efficiency is measured by the energy efficiency ratio (EER). The EER is the ratio of the cooling capacity (in British thermal units [Btu] per hour) to the power input (in watts).

The higher the EER rating, the more efficient the air conditioner.

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Viva questions What is the formula?

EER = Output cooling energy in BTU _ Input electric energy in Wh

What is the heat extraction rate?

For all-air systems the space heat extraction rate is the sensible enthalpy difference between supply and return (or room air outlet) air flows.

What is SEER? SEER stands for Seasonal Energy Efficiency Ratio. Much like the EER, it is the ratio of the cooling output to the electricity input, but the main difference is that the SEER is calculated over a whole summer season.The SEER is calculated using a constant indoor temperature throughout the season.

What is space heat gain?

The instantaneous rate at which heat enters into, out of, or generated within a space.

What is the formula of SEER? SEER = Output cooling energy in BTU over a season _ Input electric energy in Wh in the same season What is a MERV filter?

An air filter’s minimum efficiency reporting value (MERV) rating measures how effectively the filter stops dust and other contaminants from passing through the filter and into the air stream. Filters with higher MERV ratings trap small particles more effectively than filters with lower MERV ratings.

What are the different filter types?

The different types of MERV filters are Merv 1-4, 6, 8, 10, 12, 14, 16.

What is a refrigerant?

A refrigerant is a substance used in a heat cycle to transfer heat from one area, and remove it to another.

What is cooling load?

It is the thermal energy that must be removed from the space in order to maintain the desired comfort conditions.

HVAC systems are used to maintain thermal conditions in comfort range What is the purpose of load estimation?

The load estimation is used to : Derive load profile over a day Get peak load (basis for equipment sizing) To conduct operation Energy analysis To know HVAC Construction cost

What are the components of space heat gain?

The components are: • Sensible gain • Latent gain What is space cooling load?

The rate at which heat must be removed from a space to maintain air temperature and humidity at the design values What is space heat extraction rate?

The actual heat removal rate by the cooling equipment from the space The heat extraction rate is equal to cooling load when the space conditions are constant which is rarely true.

What is cooling coil load?

The rate at which energy is removed at the cooling coil Sum of: • Space cooling load (sensible + latent) • Supply system heat gain (fan + supply air duct) • Return system heat gain (return air duct) • Load due to outdoor ventilation rates (or ventilation load) What factors contribute to external loads?

Heat gains from Walls and roofs – sensible Solar gains through fenestrations – Sensible Outdoor air – Sensible & latent What are the factors that contribute to internal loads?

People – Sensible & latent Lights – sensible Appliances – Sensible & latent What is refrigeration load?

The capacity of the refrigeration system to produce the required coil load.

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Viva questions What are cooling load components?

Space cooling load – Sizing of supply air flow rate, ducts, terminals and diffusers – It is a component of coil load – Bypassed infiltration is a space cooling load Cooling coil load – Sizing of cooling coil and refrigeration system – Ventilation load is a coil load

What is effective room sensible heat gain?

Effective Room Sensible Heat (ERSH) is the sum of all sensible heat gain that occurs in the room including the gain due to the portion of the ventilation air which is bypassed.

Effective Room Sensible Heat Gain = Solar Gain of glass + Solar transmission gain through the walls and roof + Transmission gain through the walls and partitions + Heat gain – (1)Through infiltration (2) (by passed)Fresh Air + Internal heat gain + Safety factor What is grand total heat gain?

It is sum of Effective room total heat gain +outside air heat+ Return duct heat gain

What are the principles of cooling load estimate?

Enclosure heat transfer characteristics – Conduction – Convection – radiation Design conditions – Outdoor & indoor Heat Gains – Internal – External or Solar Thermal capacity

What is an elevator?

A vertical transport equipment that efficiently moves people between floors (levels, decks) of a building,vessel or any other structure.

What is bypass air?

All the air passing over the cooling coil cannot come in contact with the fins/tube surface of the coil due to the gaps between the fins and tubes. It comes out of the cooling coil at the same condition at which it entered and so it is termed as the by-pass air. The sensible and the latent heat in this by-pass air needs to be removed out. So it is a part of the room load.

What is the bypass factor?

It is the ratio of the quantity of bypass air to that of the total air passing through the coil.

What is room total heat load?

A building or room gains heat from many sources. Inside occupants, computers, copiers, machinery, and lighting all produce heat. The sum of all these heat sources is known as the heat gain (or heat load) of the building, and is expressed either in BTU (British Thermal Units) or Kw (Kilowatts).

Room total heat load (RTH) = Room sensible heat load (RSH) + Room latent heat load (RLH)

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What are the different types of lifts?

Electric Lift-It is basically electro-mechanical enabled gearless traction electric technology to send people to higher buildings.

Hydraulic Lift-These are powered by a piston that travels inside a cylinder. An electric motor pumps hydraulic oil into the cylinder to move the piston. The piston smoothly lifts the elevator cab.

Pneumatic Lift- The principle operation of the lift is based on the ascending push generated by difference in the atmospheric pressure on the top of the car and under the car. The vacuum required is achieved by turbines operating as exhaust fans, located at the top of the elevator.

Paternoster Lift-It is a passenger elevator which consists of a chain of open compartments that move slowly in a loop up and down inside a building without stopping. Passengers can step on or off at any floor they like.

What are the classifications of lift?

Drum type- In this system the car is attached to driving system by two ropes out of which one is attached to drum and other is attached to a counter weight Traction type- In this type of elevator one end of the rope is connected to pulley and another to counter-weight.

What are the factors affecting the selection of lifts?

Utility- The function must be identified whether lift is for residential, commercial, or hospital etc.

Capacity- This depends on type of building and frequency of access to lift.

Speed- This depends on no. of stops and users.

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Viva questions What are the design specifications of lifts?

Capacity: The minimum size car recommended for single purpose buildings is one suitable for a duty load of 884kg. For office buildings cars with capacities up to 2040kg are recommended as per requirement.

Speed: It depends upon quality and quantity of service desired. There are no set formulas. General recommendations are: No. of Floors Speed 4-5 0.5-0.75m/s 6-12 0.75-1.5m/s 13-20 Above 1.5m/s

What are the advantages of escalators?

It has more loading capacity and allows large numbers of people to move from one place to another at the same time.

It is more efficient as people don’t have to wait as in the case of an elevator.

Its speed can be adjusted as per crowd management and can be turned off when not in use.

What is an escalator?

Escalators are moving stairs-a conveyor transport device where the treads move on a track at an incline or decline to transport people from one floor to another.

What are its types?

Parallel Type-These are escalators which are constructed side by side or with some distance between them. These are usually at metro stations.

Multi-Parallel Type-These are the two or more escalators constructed of the same nature in parallel.

Criss-Cross Type-These are escalators which are constructed keeping the same nature of escalators on one side.

What are the components of a lift?

Hoistway or Shaft Machine room Lift pit Overheads Counter weight Guide rails Buffers What are the components of an escalator?

Landing platforms Truss Balustrade Handrail Tracks Steps

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References 5 of the fastest lifts in the world. (2017). Retrieved from https://olympiclifts.co.uk/5-fastest-lifts-world/

Evaporator-heating-coil-18290926862.html lab, B. (n.d.). Enery Technologies area. Retrieved from svach: https://svach.lbl.gov/what-isan-economizer/

10 Types Of Air Conditioners Explained (With Pictures, Prices). (2021). Retrieved from https://learnmetrics.com/air-conditioner-types/

Fairconditioning (n.d.). Retrived from: https://fairconditioning.org/knowledge/sustainablecooling-technologies/evaporativecooling/

Air conditioning.(n.d). Retrieved from https://en.wikipedia.org/wiki/Air_conditioning#:~:text=Air%20conditioning%20(also%20A%2FC,cooling%20or%20by%20

How do Hydraulic lifts work.(n.d). Retrieved from https://www.gartec.com/2018/08/14/hydraulic-lifts-work/

Air conditioning systems [Image] (n.d). Retrieved from http://www.forcefield.co.uk/ACDiag.html

Huizhou Hicool Climate Equipment co.,Ltd.(n.d.).Retrieved from: http://www.hicoolac. com/en/product/show.php?id=1

Amazon. (n.d.). amazon. Retrieved from amazon: https://www.amazon.com/LennoxCorporation-ECONOMIZER-FILTER-16X25X1/ dp/B00QW2SLNS

Indiamart. (n.d.). Indiamart. Retrieved from Indiamart: https://www.indiamart.com/ proddetail/

Ali Alahmer & Sameh Alsaqoor. (2017). Simulation and Optimization of multi split variant refrigerant flow systems. Retrieved from https://www.researchgate.net/publication/312182469_Simulation_and_optimization_of_multi-split_variable_refrigerant_flow_ systems

Keeping cool with wind effect ventilation.(2019). Retrieved from https://www.moffittcorp.com/wind-effect-cross-ventilation/#:~:text=Cross%20ventilation%20(also%20called%20Wind,vent%20 machinery, H. (n.d.). HVAC machinery. Retrieved from machinery equipment online: http://machineryequipmentonline.com/hvac-machinery/about/

Cooling and dehumidification process [Image] (n.d). Retrieved from https://www.cedengineering.com/userfiles/Air%20Conditioning%20Psychrometrics%20R1.pdf Cooling and Dehumidification process [Image] (n.d). Retrieved from https://www.brighthubengineering.com/hvac/41505-psychrometric-processes-coolingheating-and-dehumidification/ Daikin. (2014). VRV Reference Guide. Retrieved From http://www.daikinac.com/content/assets/DOC/Product%20Brochures/2017/VRVREFRENCEGUIDE0117.pdf Dehumidifier vs air conditioner. (n.d) Retreieved from https://aerindustries.com/blog/2019/02/06/dehumidifier-vs-air-conditioner/#:~:text=An%20air%20conditioner%20acts%20

MEP Engineering: Cost-Effective Comfort with Radiant Heating and Cooling. (2017). Retrieved from https://glumac.com/cost-effective-comfort-radiant-heating-cooling/ Moving Walkway. (n.d). Retrieved from https://en.wikipedia.org/wiki/Moving_walkway Natural Ventilation. (n.d). Retrieved from https://greenhome.osu.edu/natural-ventilation#:~:text=Natural%20ventilation%20is%20the%20use,reduce%20your%20home%20

Double deck elevator [Image](2020). Retrieved from https://www.toshiba-elevator.co.jp/elv/infoeng/technology/doubledeck/

New Concept on Radiant Cooling. (n.d). Retrieved from https://zenodo.org/record/3516648/files/%2812-20%29NEW%20CONCEPT%20ON%20RADIANT%2COOLIN-format. pdf?download=1

Dr. Andrew. J. Marsh. (2020). Psychrometric Chart. Retrieved from https://drajmarsh.bitbucket.io/psychro-chart2d.html

Parts of Air conditioner [Image] (n.d). Retrieved from https://www.energy.gov/articles/energy-saver-101-infographic-home-cooling

Ebay. (n.d.). ebay. Retrieved from ebay: https://www.ebay.com/itm/RHEEM-RXRX-BFF04C3-TO-6-TON-POWER-EXHAUST-FANFOR-ECONOMIZER-153603-/200606573326

Parts and working of a Split Air Conditioner. (n.d). Retrieved from https://ontime59.com/

Energy optimiser, u. (n.d.). energy optimiser, usa. Retrieved from energyoptusa: https:// energyoptusa.com/benefits-hvac-economizer/

Performance assessment of Radiant Cooling System integrated with desiccant assisted DOAS with solar regeneration. [Image] (n.d). Retrieved from https://www.osti.gov/servlets/purl/1376508

Energy performance prediction of thermoelectric ceiling radiant panels with a dedicated outdoor air system. [Image] (n.d).

Retrieved from https://www.researchgate.net/publication/319623154_Energy_performance_prediction_of_thermoelectric_ceiling_radiant_panels_ with_a_dedicated_outdoor_air_system

Radiant Cooling. [Image] (n.d). Retrieved from https://fairconditioning.org/knowledge/sustainable-cooling-technologies/radiantcooling/#1500296799565-408a1441-895b50c2af0b

Escalator. (n.d). Retrieved from https://en.wikipedia.org/wiki/Escalator

Sarang Belsare. (2020, March 22). Indirect Direct Evaporative cooling system [Video file].

Retrieved from https://youtu.be/MIcflwh8jxY

Escalator Basic Components - Part one. (n.d). Retrieved from http://www.electrical-knowhow.com/2012/04/escalators-basic-components-part-one.html

Satish Kulkarni. (n.d). Construction Basics Retold. Retrieved from https://constructionqueries.wordpress.com/tag/lift-well/

Escalator Structure and Component. (n.d). Retrieved from https://www.mitsubishielectric.com/elevator/overview/e_m_walks/e_s_equipment.html

Stack effect. (2021).Retrieved from https://en.wikipedia.org/wiki/Stack_effect

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References Sunlight and Natural Ventilation - Design Considerations. (2020). Retrieved from https://bnbarchitects.blogspot.com/2020/07/sunlight-and-natural-ventilation-design.html Thermal mass. (2021). Retrieved from https://www.greenspec.co.uk/building-design/thermal-mass/ VRF Air conditioning System Parts [Image] (n.d). Retrieved from https://www.yanmar.com/in/energy/ghp/vrf/system_parts.html

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