Urban Microclimate Scale CFD SimulationUrban Microclimate Scale CFD Simulation ... ANSYS CFD...
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Urban Microclimate Scale CFD Simulation Daniel HII Jun Chung PhD Candidate, Department of Building, School of Design & Environment, NUS [email protected] Prof. WONG Nyuk Hien (Supervisor) [email protected] 26 April 2016 2016 CAD-IT ANSYS Convergence - Singapore
Transcript of Urban Microclimate Scale CFD SimulationUrban Microclimate Scale CFD Simulation ... ANSYS CFD...
Urban Microclimate Scale CFD Simulation
Daniel HII Jun ChungPhD Candidate, Department of Building, School of Design & Environment, [email protected]
Prof. WONG Nyuk Hien (Supervisor)[email protected]
26 April 2016
2016 CAD-IT ANSYS Convergence - Singapore
Content
• Introduction: field, scale, workflow
• Examples: natural ventilation, morphology, urban heat
• Conclusion
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Introduction: Urban physics / environmental wind engineering
Link between grand societal challenges and urban physics focus areas. (Blocken, 2015)
Sketch of the urban boundary layer structure indicating the various (sub)layers and their names. (Rotach et al., 2004; modified after Oke, 1987)
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Introduction: Urban scales
Spatial and temporal scales of atmospheric phenomena and how these phenomena are treated in Reynolds-averaged Navier Stokes (RANS) mesoscale or obstacle resolving microscale models (right columns). (Blocken, 2015)
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Introduction: ANSYS CFD workflow
Autodesk AutoCAD
McNeel Rhinoceros
ANSYS Workbench
ANSYS Meshing
ANSYS Icepak
ANSYS FluentCFD-Post
CEI Ensight
ANSYS Design Modeler
Analysis &Visualization3D Modeling SolverMeshing
Turbulence model: RANS Realizable k- ε (Steady & Transient)Energy model: S2S & solar load radiation, gravity (buoyancy)
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Examples
1. Low Density: Educational - secondary school, junior college (thermal comfort)
2. High Density: Residential - high-rise housing (urban morphology)
3. Very High Density: Commercial - Central Business District (urban heat)
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Example 1: Natural ventilation for thermal comfort
Site Plan Class Plan
Class Perspective
Coral Secondary School
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Example 1: Natural ventilation for thermal comfort
North-East Monsoon period South-West Monsoon period
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Example 1: Natural ventilation for thermal comfort
Site Plan Class Plan
Class Perspective
Serangoon Junior College
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Example 1: Natural ventilation for thermal comfort
North-East Monsoon period South-West Monsoon period
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92 cases in total
Cases Distribution Worldwide
Example 2: Housing precinct morphology study
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Guancheng_Shijia, Shenzhen Spandau, Berlin Borneo_whale, Amsterdam Parque_Modelo, Mexico City
n.FAR : 3.03g.FAR: 2.69
n.FAR : 3.14g.FAR: 2.69
n.FAR : 3.17g.FAR: 2.25
n.FAR : 3.35g.FAR: 2.43
Messina_01, Paris Skyville_Dawson, Singapore Bumps, Beijing Tung_Chung_Crescent, Hong Kong
n.FAR : 3.42g.FAR: 2.79
n.FAR : 3.90g.FAR: 3.29
n.FAR : 4.08g.FAR: 3.36
n.FAR : 4.08g.FAR: 3.38
Metro_harbour, Hong Kong Shininome, Tokyo Paris_002, Paris Royal_Peninsula, Hong Kong
n.FAR : 4.65g.FAR: 3.92
n.FAR : 5.16g.FAR: 4.65
n.FAR : 5.97g.FAR: 3.99
n.FAR : 8.09g.FAR: 6.53
Some examples ofhousing typologies
Example 2: Housing precinct morphology study
A Punggol typology being normalized in the 3X3 setup
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N N N
Original site Normalized site
Theoretically homogenous context
Example 2: Housing precinct morphology study
URBAN CASES DATABASE
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Example 2: Housing precinct morphology study
Example 3: Urban heat (anthropogenic)
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Fluke TiR125 thermal imager
Roadside measurement at the bus stop in the urban canyon in the afternoon
Bus surfaces under thermal imagingRoadside measurement equipment
on the 1.2m high tripod
50°C at 14m/s (right)
50°C at 14m/s (left)
50°C at 6m/s (right)
50°C at 6m/s (left)
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Example 3: Urban heat (anthropogenic)
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Parallel Flow (Plan) Perpendicular Flow (Plan)
Example 3: Urban heat (anthropogenic)
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Parallel Flow (Left Elevation) Perpendicular Flow (Left Elevation)
Example 3: Urban heat (anthropogenic)
Example 3: Urban heat (anthropogenic)
Various vehicles in the urban canyon
North East Wind Flow
North Wind FlowEast Wind Flow
Example 3: Urban heat (anthropogenic)
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Conclusion
Schematic representation of the six spatial scales in urban physics, their typical maximum horizontal length scales and associated model categories. NWP = Numerical Weather Prediction; MMM = Mesoscale Meteorological Model; CFD = Computational Fluid Dynamics; BES = Building Energy Simulation; BC-HAM = Building Component e Heat, Air, Moisture transfer; MSM = Material Science Model; HTM = Human Thermophysiology Model. (Blocken, 2015)
-ANSYS CFD helps to solve design issues in the field of urban design, building and architecture(thermal comfort, urban morphologies, urban heat island).
-Better hexahedral + prism meshing for the field.-Availability of built material properties, models (thermal comfort), wizards (wind profile).-Realistic tree models (shading and evapotranspiration). -Better integration with mesoscale (Weather Research Forecasting), microscale (Urban Canopy Model) & building scale (EnergyPlus) simulations.
What we hope for:
