The effect of different air inlet sizes on the air flows through a stairwell.

The effect of airflow through an opening (or a crack) on the natural convection in a stairwell model is presented. The flow is driven by energy input from an electric panel heater located in the lower floor of the stairwell. The work concentrates on the effect of the size of inlet opening by varying it while keeping the area of the outlet constant. New data are presented for the measured temperatures and velocities at various cross-sections of the stairwell. The results also include gross parameters of the flow, such as the mass flow rates of the through flow and recirculating flow, heat losses from the lower and upper floors and also from the stairway. The results show that the size of the opening has a significant effect on the flows of mass and energy within, and through, the stairwell.