许登科 庞建勇 杜传梅 管二勇



摘 要:大空间分层空调送风气流属于高Re数非等温浮力流,常用的双方程模型不能较好地解决非等温气流流动时温差引起的浮力作用。为此在控制方程中添加浮力源项并进行Boussinesq假设,建立对浮力项经过修正的高雷诺数双方程数学模型。以淮北市中心体育馆分层空调气流温度实测数据为基础,对实际工况下的气流组织进行数值模拟。测试与模拟结果对比表明,所建立的数学模型以及边界条件的简化措施对高大场所气流温度场的模拟解算有良好的适用性,模型对预测高大空间分层空调系统设计的效果具有指导意义。
关键词:数值模型;分层空调;气流场;大空间
中图分类号: TU834.3 文献标志码:A
文章编号:1672-1098(2017)05-0029-05
Abstract:The air supply flow of stratified air conditioning in large space belongs to high Reynolds number non-isothermal buoyancy flow, and the common two-equation model cannot solve the effect caused by non-isothermal buoyancy flow. For this reason, the high Reynolds two-equation mathematical model modified with buoyancy was established by adding buoyancy source to the governing equation and proposing the Boussinesq hypothesis. Based on the measured air flow temperature of stratified air conditioning in Huaibei gymnasium, the numerical simulation was carried out with establishing model in operation condition. The comparison of the numerical results with experimental data showed the former mathematical model and the way of dealing with boundary conditions had strong applicability on calculating this kind of airflow; meanwhile mathematical model had guiding significance for forecasting effects on the design of the large space stratified air conditioning system.
Key words:numerical model; stratified air conditioning; air flow; large space
随着建筑技术的进步,大层高、大跨度等高大建筑得到飞速发展。如体育场馆、航站楼、会展中心、高铁站房、生产车间等[1-2]。外围护结构面积、人员密度和照明强度较大,因此空调系统冷负荷较大[3]。大空间和大层高的场所会出现室内气流层化现象,导致垂直温度梯度增加。此类建筑中央空调能耗较常规建筑大幅增加,约为建筑总能耗的45%~65%[4-5]。为了解决高大空间高能耗的问题,出现了“分层空调”技术,即利用合理的送风射流在空调区和非空调区之间形成气流隔断面,从气流上对空间进行了分层划分,建筑的上部为非空调区,下部为空调区。分层空调技术的关键是空调区和非空调区空气屏障的形成,送风气流在空调区进行热湿交换,达到消除余热余湿的目的,非空调区的热湿由机械通风排出。……