高海拔环境下离心风机性能数值模拟研究*

为研究高海拔环境下离心风机的运行性能规律，采用计算流体力学（CFD）方法对海拔高度分别为0,1 000,2 000,3 000,4 000和5 000 m条件下的离心风机流场及性能进行三维数值模拟。研究结果表明:相同工况风量条件下，风机内部流场形态不受海拔高度影响，但随着海拔的升高，内流场各处压力绝对值均减小，风机叶片载荷减小，风机蜗壳出口压力及轴功率均大致呈线性趋势降低，海拔每升高1 000 m，风机输出全压及静压分别降低9.3%及9.1%左右，轴功率降低9.0%左右。离心风机效率受海拔高度影响较小，模拟结果表明，各工况条件下，海拔每升高1 000 m，风机全压及静压效率分别平均降低0.21%和0.29%左右。研究为保证高海拔地区离心风机的高效运转及风机选型提供理论参考。

Numerical simulation research on performance of centrifugal fan in high altitude environment

In order to study the operation performance of centrifugal fans in the high altitude environment,the three-dimensional numerical simulation on the flow field and performance of centrifugal fans at the altitudes of 0,1 000,2 000,3 000,4 000 and 5 000 m were conducted by using the computational fluid dynamics (CFD) method.The results showed that under the same air volume,the form of internal flow field in the fan was not affected by the altitude,but with the increase of altitude,all the absolute values of pressure in each location of internal flow field decreased,the load of fan blades decreased,and both the outlet pressure and the shaft power of fan volute decreased with a linear trend approximately.When the altitude increased by 1 000 m,the total pressure and static pressure of the fan output reduced by about 9.3% and 9.1%,respectively,and the shaft power reduced by about 9.0%.The efficiency of centrifugal fan was less affected by the altitude.The simulation results showed that under various working conditions,the total pressure and static pressure efficiency of the fan decreased by about 0.21% and 0.29%,respectively,for every 1,000 m increase in altitude.The research provides a theoretical reference for ensuring the efficient operation of centrifugal fans and fan type selection in the high altitude areas.