The Experiment Research Of Displacement Ventilation About Many Polluting Heat Sources

This text introduced the present condition and developmental foreground of displacement ventilation, expounded the principle and characteristic of displacement ventilation, combined with the traditional mixed ventilation , This text pointed out the displacement ventilation have the advantage of specially ventilated air organize, higher ventilation efficiency, satisfying the human body's request for the hot and comfortable degree, and energy saving, and it is a kind ventilated way of all for human which has broad development foreground, but displacement ventilation lay the short and localization. This text raised the question on displacement ventilation of many pollution heat sources. Simulation experiments have been done for three pollution heat sources on such working conditions as different air-in velocity, different air-in temperature, different air outlet position, different dispersion of many sources and different heat source area. Experiment data had been drew by use of software. According to analysis ,this text drew conclusions as following:(1) Heat lamination height influenced by air-in volume especially and heat load in room. The height changes comfortably with the air-in volume. A t means the temperature difference between work area and air-in. When A t is up or down, heat lamination height is down or up.(2) Considering heat lamination height , heat load and hot comfortability, this text said A t of 3-4℃ degrees between work area and air-in is better.(3) Air outlet position didn't influence the air flow field temperature field, concentration field, heat lamination height and vertical distribution of temperature of work area.(4) Heat lamination height changed contrarily with outlet flu-gas temperature, outlet flu-gas velocity, and the dispersion of pollution sources, and Ventilation efficiency changed uniformly with the dispersion of pollution sources. If sources dispersed in somedegree, then efficiency and height is constant.(5) When pollution sources centring relatively .Energy is saved by air blowing locally and air-in volume reducing. But Energy saving must depend on the heat lamination height, ventilation efficiency and heat load eliminated efficiency.