aerodynamic city
Maria Hernandez Barbara Martinez
There are 360 degrees, so why stick to one? -Zaha Hadid
TUTOR: M. ARCH ALEX RODRIGUEZ AGO-DIC 2012
CONTENTS
BACKGROUND CONCEPT RESEARCH PRELIMINARY STUDIES ALGORITHM FORMAL DESIGN STRUCTURAL SYSTEM SKIN MASTER PLAN PROGRAM INFRASTRUCTURE SUSTAINABILITY EXTERIOR AND INTERIOR
background
'Aerodynamic City' is an alternative design for the current urban development in the Centrito Valle zone in San Pedro Garza Garcia, NL, Mexico. After analyzing the present site it was concluded that there was great visual disorganization, insufficient parking spaces, ineffective traffic flow, a lack in pedestrian sidewalks and most importantly, an absence of connection between buildings and their functions. The original purpose for this development, now known as "Centrito Valle", was to provide its neighboring residents a commercial site, primarily thought to be pedestrian, it was a place where people sought to interact with one another. Sadly with time, this has been lost. There is a great need to rearrange the functionality of this zone in order to create a bond between the context and its present needs. Through parametric urban architecture, we aim to ammeliorate the context by creating a space that will
change the way people interact.
CONCEPT
Through the use of wind tunnel analysis, along with strategies for the manipulation of winds, the intention is to create a comfort zone that will in turn become a sustainable site. The masification will be dictated by their optimum form in response to the wind tunnels created, and in turn will be able to redirect the winds in favor of the comfort of the site, reutilizing the available air and hence, reducing the site's temperature. Resulting in the creation of a microclimate for the site.
Research
Aerodynamics
is the science that deals with the study of air movement and the actions that it exerts on moving bodies immersed in it. The shape of an object greatly affects the resistance to motion excerted by the air on it. for instance, a sphere, and most prominently, a rectangular surface, oblige the air to change directions, most commonly slowing down the object. In order to create an aerodynamic surface, it needs to hardly disturb the air, in order to induce little drag from the object. Through the study of optimization of Wind Turbines we came across the use of what is called an Optimum Power Extraction Curve. Which ensures the operation of the wind turbine has optimum energy efficiency for below nominal winds and limited output power for above nominal velocities. The following curves were reached through the application of the formula:
Bernoulli’s theorem is one of the fundamental laws governing the movement of fluids, where there is a direct relationship between an increase in flow rate and a decrease in pressure.
An investigation conducted by the Museo Ideale L. Da Vinci (2009) found that the differenciation of distance between buildings could be linked with the application of Bernoulli’s Theorem. where an increase in the distance between buildings, commonly known as “gaps”, entailed a reduction in wind velocity. Also proving that in places where wind tunnels have high speeds, an increase in gap diameter can increase comfort conditions, decreasing air velocities.
Preliminary Studies
Through the use of Vasari Wind Tunnel Analysis, the existing wind tunnels were identified according to the present-day neighboring constructions.
image captured from vasari wind tunnel analysis
Wind velocities were mapped into a 3d diagram, in order to visualize the optimal placement for pedestrian walkways in order to best take advantage of existing wind currents.
Wind analysis diagram
The optimal shape for the highest points in the surface was studied by means of an aerodynamic test, from which the final shape was obtained .
image captured from vasari wind tunnel analysis
Algorithm
Urban Surface
Formal Design
Based on photographic representations of Vasari Wind Tunnel Analysis, the urban surface was created through a series of experimental masses in search for the one with the optimal solution.
grasshopper creacion de superficie
SURFACE CREATED
Derived from the study of optimization of wind turbines and taking into consideration the main buildings footprints, an average of wind velocities was calculated in order to assign the corresponding curve. The tallest builings were assigned the Power Speed Control Curve (PSCC) in order to regulate the wind speeds.
Power Speed Control Curve Optimum Power Extraction Curve
A rectangular grid was created
The highest points were identified
These were assigned as attractor points, which had different radiuses and forzes of attraction.
the grid was deformed
Intersection points for these lines were foiund in order to create the diagrid.
structural system
Formal Design
The urban scheme works as a system were the diagrid serves as a single structural optimized system. Diagrids provide very efficient structural systems due to the triangular configuration of their structural members. Consequently, due to their inherent structural efficiency, diagrids can be designed with a small amount of structural material. Due to its triangular configuration , it contains very high lateral stiffness, which allows for no exterior vertical elements and promises structural efficiency and strength. Therefore diagrids have less probability of lock-in-condition.
Found to work best at an optimal angle range of around 5863째 for 15-20 story buildings, diagrid structures have a lower probability of the vortex frequency locking in on a modal frequency, most frequently caused by high wind velocities.
With the method outlined above, the intersection points were then connected into a diagrid, which was in turn proyected onto the urban surface in order to create the structure sought. grasshopper diamond panels
Solar Radiation
Formal Design
With the help of the algorithm “Annual Solar Incidence� created by Ted ngai, we were able to compute the solar radiation on each individual panel, therefore enabling us to regulate the openings in each panel.
Once the latitud and Longitud coordinates were set for our site, several iterations regarding the time of the year were made in order to best protect the buildings from solar radiation.
january
april
august
november
SKIN
Formal Design
Taking into consideration the range yielded by the Solar Incidence definition, each panel was assigned a scaled opening, where the panels with the least amount of radiation were 98% window, and the panels most affected by the sun were considered completely closed.
LANDSCAPE
Master Plan
According to the picture originally drawn from Vasari, the main wind tunnels are used as attractor curves, analizing all neighboring panel center points, enabling those closer than 15 m to become the main pedestrian walkways.
Infrastructure Vehicular transit is then generated proceding the same definition, where the main wind tunnels which have proximity to present-day roads are used to generate roads crossing the site.
Slabs
In order to create slabs, floors were predestined to be 4 m apart, all of which were then sliced by the surface itself, creating the slabs shown below.
Sections CommerceD
Residential
Business
Program
The program was selected by means of closeness to main boulevards, where offices and business centers were located. Residential areas were defined as the furthest from the chaotic streets, and with the most green. Seeing as Aerodynamic City is meant to become a cultural center, an auditorium was assigned to one of the buildings, where acustics would be best. A commercial zone resulted as the mid-point between these programs, and as a result of the intersection of slabs, which in turncreates one big shopping center.
infrastructure parking is provided as an underground parking zone, where vehicles can access by 5 different accesses. All Landscape was preserved as permeable area.
Sustainability
Solar Panels were incorporated into the panels which have the most solar radiation, therefore resulting in the ones where there was the most opportunity for energy captivation. Each building has at least one of these systems.
green Walls were utilized in order to keep the inside of buildings cooler, and hence, provide a better landscape.
A microclimate is achieved by the mere form of the buildings, where the building shown on the left is used to redirect the wind, bouncing off the second building, the wind begins to travel down through a vent in the facade which in turn cools the air which is then fed back to the atmosphere approximately reaching 3 degrees in temperature difference.
view business center
View into Business Center
View from neighboring streets
view from neighboring boulevard
view from neighboring street
view entrance commercial center
Conclusion
By means of strategies utilizing passive air cooling systems and wind and solar energy, The urban surface proposed is successful in creating a microclimate with almost total comfort for pedestrians in relationship with the buildings. In relation to the wind tunnels that were studied previous to this architectural approach, the resulting surface (shown below) has little effect on the pre-existing wind tunnels, and in turn has created some that were not there to begin with, increasing the pedestrians comfort by achieving a decrease in ambiance temperature.
vasari Wind Tunnel Analysis
Maria Hernandez Barbara Martinez