公路冷藏运输车厢内三场协同性三维数值模拟与试验

Three-dimensional Numerical Simulation and Experiment of Three Fields Cooperative in Refrigerated Road Transport Carriage

在公路冷藏运输车厢内温度场和速度场协同控制基础上,从能量守恒协同方程和湍流动能方程出发,设置传热工质空气参数,探讨其速度场和压力场的协同性。以温度均布为评价目标,从定性角度验证冷藏车厢内沿纵向截面三场的模拟仿真分布情况,并分别对圆形孔、椭圆形孔和正六边形孔进气匀流板的换热及低阻性能进行数值模拟比较与分析。冷藏厢内进气道采用椭圆形孔进气匀流板后,在满载过程厢内温度沿厢体宽度方向的最高温度由2.53℃降为1.27℃,温度标准差由0.642℃降至0.332℃。结果表明该进气道的流动阻力较小,有效减少制冷机组的泵功损耗,温度分布更加稳定且均匀,速度场、温度梯度场和压力梯度场三场有较好的协同性。

Taking advantage of research results about cooperative control of flow field and temperature field,the cooperative of velocity field and pressure field were further investigated by setting up indispensable parameters of heat transfer medium in refrigerated road transport carriage,according with start points of energy conservation synergistic equation and turbulent kinetic energy equation. Considering temperature distribution homogeneity as evaluation objective,the simulation distribution condition of three fields in longitudinal cross sections was qualitatively analyzed and experimentally verified. The heat transfer and pressure drop performance were fulfilled using numerical simulation analysis and comparison method for inlet orifice with three different shapes as circle holes,elliptic or regular hexagon. The test data of inside temperature in refrigerated transport carriage in fully loaded process showed that the highest temperature in cross sections with width direction dropped from 2. 53℃ to 1. 27℃,and the standard deviation amplitude of temperature values dropped from 0. 642℃ to 0. 332℃,respectively. The results also demonstrated that the flow resistance of elliptic air inlet orifice was smaller than other two shapes,and the consumption power of refrigeration motor-pump was fewer. The temperature distribution was more stable and homogeneity,and velocity field,temperature gradient field and pressure gradient field had favorable harmonious degree.