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Historical UK Pressure Extremes

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02. Fluid Dynamics of the Upper Atmosphere

Simulating high altitude wind flows and heat exchanges through high & low pressure systems

Set-Up Diagrams

Modelling geometry to process in CFD to achieve an illustrative output that demonstrates: The movement of air particles in the jet stream (1), the thermal exchange in a vertical column of air - as occurs in a high or low pressure system (2) and the global scale thresholds of temperature in the mid-latitudes. Solid geometry serves as volumes of air, their boundary surfaces used as inlets and outlets for velocity, pressure, volume flow rate, and heat exchange.

Patterns in the Northern Hemisphere

Simulating global atmospheric circulation through chamfered spherical geometry, with cylindrical nodes representing cyclones and anticyclones, and heat exchange between the the cool northern and warmer southern latitudes.

Thermal Flows of the Northern Hemisphere

Cyclonic & Anti-Cyclonic Behaviour

Introducing the vertical column of air that transports thermal energy between the jet stream and ground level. The opposing characteristics of rotational velocity, vertical air flow and thermal exchange between the cyclone and anticyclone allowed for two simulations using the same geometry, swapping over the inlet and outlet surfaces.

Anti-Cyclonic Temperature Divergence

Revealing the thermal thresholds at different heights within the air column that forms around an anti-cyclone: the typical high pressure system that forms in the ridges of the jet stream.

General air particle movement is from West to East though in a cyclone or anticyclone the particles have rotational velocity. In an anti-cyclone, cool air sinks. and there is convergence at the top of the column.