Towards the determination of regional purging flow rate

This paper deals with the description and determination of the purging flow rate, Up, for ventilation systems or equivalent flow systems. The regional purging flow rate and its use are discussed and proposed. By using the mass conservation principle, Up is embodied in various accessible mathematical expressions in terms of the transfer probability. Some Up-related parameters are described. A Markov chain model is proposed for determining the transfer probability and exploring several useful ventilation indices. An effective CN method is proposed for calculating the interchanging flow rates between various regions. The application of these proposals is demonstrated, and they appear to be promising for analyzing and assessing ventilation performance.