ANALYSIS OF WIND-DRIVEN FLOW AND EXTERNAL CONVECTIVE HEATTRANSFER COEFFICIENTS FOR THE BESTEST MODEL BUILDING

摘要

Building energy analysis are very sensitive to externalrnconvection heat transfer coefficients so that somernresearchers have made sensitivity calculations andrnproved that depending on the choice of convectivernheat transfer coefficient values, energy demandsrnestimation values can vary from 20 to 40%. In thisrncontext, a Computational Fluid Dynamics (CFD)rnprogram has been used to predict external convectivernheat transfer coefficients at external buildingrnsurfaces. The simulations have been carried out usingrnthe building model presented in ANSI/ASHRAErnStandard 140-2001 – Standard Method of Test for thernEvaluation of Building Energy Analysis ComputerrnPrograms in the Building Energy Simulation Testrn(BESTEST). For the BESTEST house model, effectsrnof wind speed and temperature differences betweenrnthe surfaces and the external air have been analyzed,rnshowing different heat transfer conditions andrncoefficients.