The indoor air flow pattern in a single heated space with wind leakage from rail windows.

Abstract

The wind and buoyancy forces acting on a naturally ventilated building that has a distributed heat source on the floor can lead to multiple steady state regimes. These two driving forces are also present in a building with leaky windows. However, in this case the vents vary in size and location. This difference is expected to result in different flow dynamics. In this study, we are interested in studying the interior flow pattern and thermal behavior of a single building space fitted with the rail-type window design that prevails in buildings across the Middle East. This popular window design is inherently leaky, and air leakage in the winter months can lead to poor thermal comfort and-or increased heating bills. We apply particle imaging velocimetry PIV and thermometry to probe the interior flow of a model building with a prescribed pattern of small orifices to represent leaking sites of a window. The results from the naturally ventilated model and air infiltrated model show similar regimes and global energetic, while varying interior flow patterns. The temperature measurements show comparable results indicating that the physics behind natural ventilation and air infiltration are alike.