A new method for linking results of detailed air flow pattern calculation with multizone models.

Multi-zone models are a common tool for calculating air and contaminant exchange within rooms of a building and between building and outdoors. Usually a whole room is then modelled by one calculation node with the assumption of homogeneously mixed conditions within this room whereas in real cases temperature and contaminant concentrations vary in space. The exchange to the neighbouring nodes via the flow paths is then a function of the local values of these variables. Detailed knowledge can be obtained from the solution of the transport equations for the air flow pattern within the room at the expense of far higher computation cost. This work shows a new approach called "method of detailed node values" to include results from detailed calculations in multi-zone models to give a better description of the real cases. Parameter transfer between a multi-zone program and a detailed air flow simulation program is discussed for different flow paths of practical imortance. The method is demonstrated in an example case with air in/exfiltration, ventilation and contaminant propagation, and discussed in a second example with large openings. This new method promises to improve the multizone model predictions with few additional CFD computations.