Experimental study of a non-isothermal wall jet issued by a displacement ventilation system

• Experimental study of a large displacement diffuser.
• Analysis of the velocity, temperature and turbulence intensity fields.
• Study of the flow physics of a thermal wall jet.
• Study of the effects of thermal buoyancy.

This paper reports a new set of experimental data and presents an in-depth analysis of the flow physics of a non-isothermal jet stream produced by a large quarter-round corner-mounted displacement diffuser. The air velocity, temperature and turbulence intensity inside the displacement ventilation (DV) jet have been thoroughly analyzed and compared with the reported findings of previous studies and model predictions. Through the experiment, it is observed that the DV jet development is significantly altered by buoyant forces and can be divided into four distinctive zones. The results of the present study refine the physical understanding of the coupled thermal-fluid fields characteristic of a DV jet stream, and are useful for improving the design of the DV system tested.