Scaling of air flow patterns in room ventilation.

Is it possible to translate a computed flow field to a design case with different physical dimension? - This and related questions must be answered when the results of the "air flow pattern atlasM, as proposed in the IEA Annex 20, should be applied to actual ventilation systems. Looking up a case in the atlas and transforming results to an actual application is like interpolating in a table. If geometries are similar, scaling laws may be applied. The interpolation problem also arises when numerical or experimental data from literature must be translated to a case at hand. Scaling rules show whether and how measurements on scale models may be translated to full-scale. The poster identifies dominant physical parameters of jet- and buoyancy-driven air flows in rooms. It lists non-dimensional parameters that are important for the air flow and those that are not. The difficulty of running scale-model tests for natural convection in large spaces is analyzed.