室内置换通风与混合通风的效果对比  

Comparison of ventilating effect of indoor displacement and mixing ventilation

作　　者：袁建平[1] 王龙滟[1] 何志霞[1] 刘晓凡[1] 

机构地区：[1]江苏大学流体机械工程技术研究中心,江苏镇江212013

出　　处：《排灌机械工程学报》2012年第5期563-566,577,共5页Journal of Drainage and Irrigation Machinery Engineering

基　　金：国家自然科学基金资助项目(50979034);江苏大学高级专业人才科研启动基金资助项目(09JDG032)

摘　　要：通过采用试验验证了的计算流体动力学模型开展数值模拟,从热舒适性和室内空气品质两方面,研究在商业厨房环境采用置换通风方式和混合通风方式的性能差异.研究发现,使用置换通风系统能够在不增大空调系统工作负荷的情况下,降低室内温度.在同样室内条件下,混合通风系统气流速度平均约为置换通风速度的2倍左右,并且上升下降气流相互交叉运动,气流相对不均匀.置换通风系统温度分布有明显的分层现象,从下到上逐渐递增,且大概在人呼吸的高度有较合适的温度值.其次,置换通风在呼吸区的空气质量,通常比在一个同样气流速度运行的混合系统要好.且在厨房环境中,呼吸区的平均空气年龄均小于100 s.通过适当的设计,置换通风能保持良好的热舒适环境,空气流速一般低于0.3 m/s,头和脚踝的温差小于2℃,呼吸区不满意百分数小于15,可以在人体所在区域提供更好的空气质量.The main objective of the article is to investigate the difference in indoor thermal comfort and air quality by means of numerical simulation based on a well-validated CFD（computational fluid dynamics） model when a commercial kitchen is subject to mixing and displacement ventilation.It was shown that using thermal displacement ventilation in the kitchen can reduce indoor temperature without increasing the air-conditioning system capacity.Under the same indoor environmental conditions,the flow velocity of mixing ventilation（MV） is almost twice that of displacement ventilation（DV） in ave-rage,and the cross-drafts exists which leads to an uneven flow pattern.The temperature stratification is evident for DV,the temperature gradually gets higher upwards,and it has an appropriate value in the human breathing zone.Also,the air quality in the human breathing zone of DV is better than that of MV system which operates in the same air velocity.Moreover,the average air age of the former is less than 100 s in the kitchen.A properly designed displacement ventilation can maintain a thermally comfortable environment where the air velocity is lower than 0.3 m/s,the difference in temperature is below 2 °C between the head and ankle level,and the percentage dissatisfied people in breathing zone is smaller than 15%,and eventually can provide a better IAQ（indoor air quality） in the occupied zone.

关 键 词：商业厨房 热舒适性 室内空气质量 置换通风 混合通风 数值模拟 

分 类 号：S277.9[农业科学—农业水土工程] TH311[农业科学—农业工程]