Numerical Simulation On Diffuser Type's Affect On Ventilation Efficiency Of Displacement Ventilation

Compared with mixing ventilation, displacement ventilation has a lot of advantage, for example, it can afford a more clearing indoor environment, and has a notable effect on saving energy. But when installing diffures, traditional displacement ventilation was limited, up-fixing diffures of displacement ventilation was put forward. Up-fixing diffures is favor for engineering use.This paper based on our studying group's test-bench of up-fixing diffures of displacement ventilation, used CFD to simulate diffures'type affect on ventilation efficiency of displacement ventilation with up-fixing diffures, and verified the results with existing experiment datas of our studying team has got. The simulation mainly contents the flowing details: how dose the change of plate's angle inclination affect on the indoor airflow, temperature, velocity, thermal comfort and ventilation efficiency; how dose the change of the length of ventilation attachments in the air box affect on the air draft and ventilation efficiency; how dose the diffures length breath ration change affect on indoor air distribution and ventilation efficiency. Based on thermal comfort, choose the best diffures' type for up-fixing diffures displacement ventilation which has the largest ventilation efficiency.Up-fixing diffures of displacement ventilation is the conbained flow of active and passive ventilation, so used indoor zero equation, and SIMPLE arithmetic, dispersed the equation with FVM, mashed the gird with unwell-distribute structured grid. At the different boundary conditions, the writer did a lot of simulation about the research subject. By analysis the result of the simulation, found ventilation ratio p, the length of ventilation attachments h and diffures length breath ration has some affection on ventilation efficiency.