Analysis and modeling of building thermal response to investigate the e ect of boundary conditions

Thermal load simulation and sensitivity analysis are performed for a buildingin tehran by numerical means. a heat conduction equation of the walls, together withappropriate convection and radiation boundary conditions, is simulated numerically tocompute temperature distributions in the walls. this research proposes a heat balancemethod, coupled with a bulk model, to calculate the building thermal load. in the rststep, the results of the building thermal load for weather data of tehran are comparedand validated with those of carrier hap software, and a good agreement is found betweenthem. the building thermal load depends on the boundary conditions of the building.the inuence of the boundary conditions, such as the emissivity of interior and exteriorsurfaces of the walls and convective coecients, on the building thermal load, is investigatedthrough the application of a sensitivity analysis. then, the sensitivity coecients, whichdemonstrate the signicance and impact of internal and external boundary conditionsof walls on the thermal load of the building, are calculated, numerically, using a nitedierence method. the results show that internal radiation is an important component ofthe building energy balance.