The influence of ceiling-mounted obstacles on the air flow pattern in air-conditioned rooms at different heat loads

Abstract

Ceiling-mounted obstacles may disturb the flow in air-conditioned rooms, resulting in a downward deflection of the supplied air jet. Dimensional analysis and experiments quantify the most important parameters of this problem and it is shown how a deflection of a jet necessitates a reduction in the supply velocity and indirectly reduces the ability of the system to remove heat from the room. The results in the paper are valid for typical rooms with sill-mounted induction units and it is shown how they can be used to express the running conditions for such a room. The experiments are both isothermal and non-isothermal and they are made in different full-scale rooms with induction units and in a model-scale room with a linear slot inlet at the ceiling.