静压箱对地板送风气流组织与温度分层的影响

Impact of Plenum on Air Distribution and Thermal Stratification in Underfloor Air Distribution System

研究了地板送风系统在办公室的应用效果,重点考虑了静压箱对室内空气流动和热力分层效果的影响.首先通过现场实测得到有静压箱存在时室内的实际温度分层效果,然后采用数值模拟的方法定量分析了静压箱内得热对室内热环境的影响.发现静压箱内的空气温升承担了约40%左右的室内冷负荷,导致送风温度偏高,室内温度分层特性衰减,人员工作区整体温度升高,增大送风量会进一步减小竖直温度梯度.应当重视静压箱对室内热平衡和流场、温度场的影响,做好架空地板的防漏和保温措施,才能充分发挥地板送风的优势.

The real performance of under-floor air distribution （UFAD） system in the office was studied by focusing on the impact of plenum on the indoor air motion and thermal stratification. The practical thermal stratification in an office with under-floor plenum was tested first. Numerical simulation was adopted to quantificationally analyze the impact of heat gains in the plenum on the indoor thermal environment. The results show that the air in the plenum undertakes approximately 40% of indoor cooling load. The supply air temperature from air diffusers increases, leading to the decay of thermal stratification. The increase of flow rate will decrease the vertical temperature gradient as well. More attention should be paid to the influence of plenum on indoor thermal balance and flow field. The advantage of UFAD system depends on the good sealing and thermal insulation measure at the raised floor.