Models for the prediction of room air distribution.

The paper describes work on simplified design methods made in connection with the International Energy Agency programme "Air Flow Pattern within Buildings", Annex 20, subtask 1. It is shown that simplified models are able to indicate design values as the maximum velocity in the occupied zone and penetration depth of a non-isothennal jet in a room. The design according to throw of an isothermal jet is a fully developed method which has a sufficient level of accuracy when it is used in regular rooms. Models for prediction of the maximum velocity in the occupied zone and penetration depth of non-isothermal jets need further development. The possibility of Computational Fluid Dynamics (CFD) is evaluated and it is compared with simplified models. It is shown that the CFD-method is special useful because it gives the distribution of the variables as well as the design values. The CFD-method can also predict variables which are time consuming to measure by full-scale experiments. The CFD-method is especially useful for the prediction of air distribution in large enclosures with complicated geometry and different sources for the air movement.