Comparison of experimental and numerical test results of the airflow in a room with displacement ventilation.

The paper presents a comparison between the results of experimental tests airflow pattern forming in a room with displacement ventilation and numerical calculation. The heat source in the room was a heating plate. Quasi-laminar diffusers supplied the air with the ventilation change rate from l to 7 h-1. Temperature and velocity distributions in the plume and in its surroundings as well as the tracer gas concentrations in the background were measured. The airflow in the room was also predicted by means of CFD, using the standard k-E turbulence model and standard log-law wall-functions. The long-wave radiation between the walls was considered. Boundary conditions in the diffusers, on the walls and those of the heat source used for numerical prediction came from experimental data. By comparing the results of measurement and calculation of non-dimensional vertical air temperature distribution, tracer gas concentration, distribution of parameters in the plume and changes in the plume velocity flux, the k-E turbulence model applicability to displacement ventilation was verified.