Research on numerical analysis method of sensible heat flux from building external surfaces in an existing old residential district

The renovation of existing residential district is being promoted in major cities across China, including Shanghai. Therefore, it is important to improve the thermal environment in surrounding areas of buildings. Sensible heat flux from building external surfaces is a key factor influences the thermal environment. In order to clarify sensible heat flux, it is significant to understand the distributions of Convective Heat Transfer Coefficient (CHTC) and surface temperature. This study used 3D CAD-based thermal-environment simulator which can calculate building surface temperatures by heat balance simulation. By coupling the heat balance simulation with Computational Fluid Dynamics (CFD), the study examines the relationships between wall-adjacent wind velocity and CHTC to derive a prediction equation which can apply to the prediction of CHTC for High Reynolds number k-ε model (the High-Re model). Finally, the study examines the prediction accuracy of the prediction equation by comparison with the Jürges equation. The results show that the prediction equation for the High-Re model is appropriate for predicting the sensible heat flux from the building external surfaces under the forced convection field.