Numerical study of airflow structure of a cross ventilated model building.

With the purpose of evaluating validity of the application of CFO on the problems of cross-ventilation, numerical simulation was performed, using standard k- E model and two types of modified k-E models which improve evaluation accuracy in production term of turbulence energy, and also using LES, and the results were compared with those of the corresponding wind tunnel experiment. As a result, it was found that the defects of the model characteristic to the standard k- E model could be improved to a certain extent by application of the modified models. However, from the reasons that the effects of improvement are not necessarily remarkable, it was judged that the standard k- E model could be applicable to a certain extent in case general cross-ventilation phenomenon is to be predicted. On the other hand, when LES is used, the factors such as wind pressure coefficient, turbulence energy, etc. are more accurately reproduced than k- E type models. Based on these results, the results of calculation of LES were separately assessed, and turbulence structure specific to cross-ventilation was evaluated