IMPACTS OF AN EVAPORATING WATERBODY IN URBAN FABRIC THROUGH CFD SIMULATIONS

The evaporation and condensation of water are crucial phenomena that drives many physical processes in urban environment both in terms of buoyancy force generated and heat sink or source introduced. This work presents and implements a general evaporation and condensation model that includes the heat exchange due to the water change of phase. Such a general approach can be applied to different simulation techniques link RANS and LES. Two geometries paradigmatic of a city fabric are investigate under a mixed convective regime and considering waterbodies which are set to be warmer and colder compared to the building temperature. Globally, the water evaporation leads to an increase of convective motions that enhance the vertical transport and the turbulent mixing between urban canyons and the surrounding atmosphere. To the best of the authors knowledge, this is one of the first study directly reproducing the evaporation form a waterbody in urban context.