风送式喷雾机喷筒结构优化数值模拟与试验

摘要

采用动参考系模型,将可动风机的转速作为仿真的初始值,分段划分喷筒内计算区域中的网格,利用数值及正交试验的方法,对风送式喷雾机的喷筒结构进行了优化设计,仿真计算喷筒出口处的风速.为验证模型的正确性,在对应风机转速下,实测了喷筒出口各采样点的风速,并将实测值与仿真结果进行了覆盖率统计及x2检验.结果表明:影响喷筒压力损失及喷筒出口风速的因素依次为:出风口直径、柱形喷筒长度、锥形喷筒长度；在喷筒出口采样点上,仿真计算出的风速区间覆盖实测风速的概率为95％；x2检验表明在水平0.05下,喷筒出风口风速的仿真值均服从其实际测量值的分布；因此,利用动参考系方法,以风机转速为初始条件,对喷筒出风口速度的数值模拟是可信的.%Taking the rotation speed of mobile fan as the initial value of simulation,grids within the computational regions inside the air duct were divided into sections based on the dynamic reference model.The structure of air-blast sprayer was optimized by using numerical experiments and orthogonal experiment.The flow speed at the outlet of air duct was simulated.In order to verify the correctness of model,flow speed at the outlet of air duct was measured at each corresponding fan rotation speed.The coverage rate statistics and x2-test were carried out between measured and simulated value.The results indicated that the order of factors which affected the duct pressure loss and outlet flow speed was:the diameter of outlet,the cylindrical duct length and the tapered duct length.Meanwhile,at the sampling spot of air duct outlet,the measured flow speed in simulation was 95％.The simulated flow speed at the air duct outlet was submissive with the measured distribution when x2-test result was under 0.05.It was reliable to simulate outlet flow speed of air duct by using dynamic reference model with fan rotation speed as initial value.