Simulation of Natural Drafts and Ventilation in Void Spaces in 3-D Densely Built-up Area Models

Abstract

   In this paper, airflow and concentration calculations in void spaces in 3-D densely built-up area models are done for study on relationship between configurations of the models and performances of natural drafts and ventilation of them. In a center block in the first model, there are ten buildings around a road with width of 4m and length of 40m, which has a dead end and another end opening to a road with width of 7m, and the clearances between walls of buildings are 1m. Fifteen almost the same blocks are set around the center block. Another two models are also set with slightly different city configurations. The gases are supplied from four points on the road surface only in the center block in 3 cases. The simulations are done using 3 models and the tendencies of ventilating performances for 3 levels of city density in the models are obtained.