Numerical simulations of wind-driven rain on building facades under various oblique winds based on Eulerian multiphase model

Wind-driven rain (WDR) is an important factor affecting the hygric behavior and durability of building facades. In recent years, CFD simulations of WDR impinging on building facades almost have been focusing on isolated buildings for wind directions perpendicular to the facades. Very few efforts have been made towards study of complicated WDR on buildings considering group effect and the effect of varying wind direction. By virtue of the WDR simulation approach based on the Eulerian multiphase model, this paper presented a validation study of CFD simulations of WDR for an array of low-rise building models provided by recently field measurements. The simulation results suggested that CFD simulations can provide fairly accurate estimates of WDR for complex situations by the present method. And simulations of WDR are performed for a single building and building complex, analyzing the characteristics of catch-ratio distribution with various wind directions and focusing on the impact of group effect and varying wind direction on WDR. The differences of WDR distribution on the building facades are presented and discussed by comparing the results of the single with those of the complex. The conclusions in this paper can provide references for further research of WDR and design of engineering.