主扇扩散器出口速度分布的数值模拟与实验研究

Numerical Simulation and Experimental Research on the Velocity Distribution in Outlet of Main Fan Diffusers

借助重整化群双参数湍流模型,建立扩散器内风流流动的控制方程组。基于工程实际,给定模拟边界条件进行数值模拟,并分析扩散器的出口速度分布。根据大量的数值模拟算例,获得节能型扩散器的最优断面扩大系数,找出扩散器出口速度分布与扩散器动能回收之间的关系。通过对节能型扩散器的多工况模型实验,对扩散器出口速度分布进行研讨。借助数值模拟实验与模型验证实验,揭示了扩散器结构形式与扩散器出口动压能损失分布之间的关系。

By virtue of RNG turbulent model, the control equation group of airflow flowing inside the diffuser was firstly built. Then, based on engineering actuality, numerical simulations were conducted with given boundary conditions, and velocity distributions in the outlet of diffusers were analyzed. According to many numerical simulation calculating examples, the optimal section expansion coefficient of energy-saving diffusers was obtained, and the relation between dynamic energy recovery by diffuser and the velocity distribution in diffuser outlet was found out. The velocity distributions in the outlet of diffusers were explored through simulating different working conditions of energy-saving diffusers. Finally, based on simulation test and model verification test, the relation between the structural type of diffuser and the loss distribution of dynamic pressure energy in diffuser outlet was disclosed.