SERVICES FOR MODELING OF BUILDING AERODYNAMICS
SIMULATION OF FLOW AROUND BUILDINGS
This is an alternative to the wind tunnel simulation aimed at determining the in-situ distribution of velocities and harmful impurities, building loads, etc., as well as calculating wind loads on structures and their pressure coefficients.
Wind Load Simulation, Determining Pressure Coefficients
Wind load simulation is required when constructing new buildings and structures. However, the wind tunnel simulation is required to calculate wind loads provided that the building height exceeds 75 meters. Either a physical wind-tunnel experiment or a CFD&BEM modeling can be used to perform such simulation.
Wind load simulation using CFD&BEM modeling has been increasingly gaining popularity lately.
Modeling of building aerodynamics includes the following:
1. Simulation of flow around buildings/structures in 24 wind directions with 15° increments using CFD&BEM modeling methods (CFD calculations).
2. Determination of pressure coefficients for buildings/structures.
3. Wind load calculation for buildings/structures.
4. Determination of peak pressures on facade structures.
The results of simulation of flow around buildings are presented in the form of:
— Force fields created by an air flow around buildings/structures.
— Pressure distribution over the surface of the building/structure, including “small” elements.
— Values of forces and pressure coefficients.
Terrain features and surrounding buildings should be considered to perform modeling of aerodynamics of buildings/structures.
The results of wind load simulation are presented in the form suitable for further transfer to strength calculation programs.
CFD Modeling of Pedestrian Level Wind Velocity and Wind Comfort Assessment
Pedestrian wind comfort is an important indicator for outdoor public areas. Particularly difficult situation may arise in the pedestrian area near high-rise buildings. The CFD&BEM modeling of air flow around buildings in the context of the urban building renders it possible to analyze in detail the aerodynamic conditions and pedestrian wind comfort.
The obtained information should be used when:
— Planning and developing the surroundings, including when locating children’s playgrounds, garbage collection areas, pedestrian paths, etc.
— Constructing the complex of buildings to determine their mutual arrangement that prevents strong air gusts from occurring in the pedestrian area.
Simulation of pedestrian level wind velocity includes the following:
1. Simulation of flow around buildings and surrounding buildings in 8 wind directions with 45° increments using CFD&BEM modeling methods (CFD calculations).
2. Analysis of pedestrian level wind velocity fields. Location and causes for occurrence of local areas with increased velocities.
Analysis of Air Discharge Overflow into Air Intakes
The walls of buildings should have air intakes and discharges positioned in such a way as to prevent the air discharge from overflowing into the intake of the draw-in ventilation system.
Adverse effects from overflow:
— Reduced air quality in the ventilated premises;
— Unpleasant odors entering the intake air;
— Reduced air flow of CO2 sensors installed in the premises due to reduced energy efficiency of HVAC systems.
Modeling of building aerodynamics using CFD&BEM modeling methods makes it possible to analyze the air discharge overflow into air intakes.
Simulation of air distributed from air discharge chambers includes the following:
1. Simulation of flow around buildings and surrounding buildings in 8 wind directions with a wind velocity typical for the facility location, as well as under zero wind conditions.
2. Analysis of the velocity fields near air intakes and discharges to ensure that no air discharge enters the air intakes of the building.
3. Development of recommendations for the avoidance of air overflows in the event of undesired air overflows.