THE MAIN INFLUENCE ON INDOOR THERMAL ENVIRONMENT OF AN OFFICE WITH COMBINED SYSTEM OF CHILLED PANEL AND DISPLACEMENT VENTILATION
Choosing proper combined cooling parameter is an important step in designing combine air-conditioning systems of chilled panel and displacement ventilation. Different combination may bring about different indoor thermal comfort as well as different operational cost. To this end, CFD simulations were conducted on an office with a combined system to reveal the influence of different combination of cooling parameters. Firstly, the impact of the location of heat sources and air inlet on indoor thermal environment were investigated, when the cooling parameters were kept constant. Then, the individual influence of such cooling parameters as supply air flow rate or temperature of DV, the surface temperature or the area ratio of CP to the ceiling on indoor air temperature and velocity distribution were studied. It shows that the lower the air supply flow rate, the stronger the buoyant force plays on the room air movement, and the less the convection fraction from the chilled panel to the room air. The higher the supply air temperature of the DV, the lower the vertical temperature gradient it creates in the occupied zone. Ventilation efficiency also improves as it rises, while the cooling capacity of CP decreases somewhat. It was found that the temperature gradient in the occupied zone drops as the surface temperature of the CP drops scarifying ventilation efficiency. The enlargement of the area of CP brings about the drop of air temperature in the upper part of the room. And then, the influence of a change in the exterior wall face temperature on the indoor environment was explored. Cooling parameters were adjusted pursuing optimal combined parameters to maintain the original PMV.
Lei ZHAO Feng YUAN M.Zaheeruddin
School of Environ. & Muni. Engi., Xi’an University of Architecture and Technology,Xi’an, 710055, Chi Dept. of Building, Environmental and Civil Engi., Concordia University,Montreal, H3G 1M8, Canada
国际会议
The 22nd International Congress of Refrigeration(第22届国际制冷大会)
北京
英文
2007-08-21(万方平台首次上网日期,不代表论文的发表时间)