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以矿用对旋式轴流通风机为研究对象,应用计算流体力学软件FLUENT对通风机气动噪声及三维流场进行数值模拟与分析,研究矿用对旋式轴流通风机气动噪声产生机理及通风机内部三维流场的流动状况;在三维非定常流动条件下,采用大涡模拟湍流模型(LES)进行求解,选取二阶隐式时间推进法来提高计算精度,结果表明:受前后两级叶轮之间所形成的流道不均影响,在同一轴向截面上靠近叶轮壁面位置的噪声值小于叶轮流道中部位置的噪声值,而叶轮流道中部位置的噪声值又小于靠近轮毂壁面位置的噪声值.离通风机气动噪声源(前后两级叶轮)越近,受到的气流压力脉动的影响就越大,则该区域气流的振动也越大,其对应的噪声值就越高;反之,越远离噪声源的区域受到的气流压力脉动的影响就越小,使得该区域的气流的振动越小,其对应的噪声值越低.同时,高压旋转的气流在扩散器区域的分布不再均匀,靠近叶轮壁面及轮毂的动压较低,而通风机流道中部附近的动压较高.研究结果对矿用对旋式轴流通风机的优化设计具有一定的指导意义.
Taking the mining counter-rotating axial fan as the research object, the numerical simulation and analysis of the aerodynamic noise and the three-dimensional flow field of the fan are carried out by using the computational fluid dynamics software FLUENT, and the aerodynamic noise generation mechanism of the mine counter-rotating axial fan is studied. In the case of three-dimensional unsteady flow, LES is adopted to solve the problem. The second-order implicit time-based method is adopted to improve the calculation accuracy. The results show that, Impeller is formed between the uneven runner, in the same axial cross-section near the impeller wall position noise value is less than the central part of the impeller runner noise value, and the middle of the impeller runner noise value is less than the position near the hub wall Of the noise value from the fan aerodynamic noise source (before and after the two impeller) closer to the impact of air pressure pulsation is greater, then the regional air flow greater vibration, the higher the corresponding noise value; the other hand, , The farther away from the noise source is less influenced by the pressure pulsation of the air flow so that the smaller the vibration of the air flow in this area is, the lower the corresponding noise value is. At the same time, the high-pressure rotating air flow The distribution of the diffuser area is no longer uniform, the dynamic pressure near the impeller wall and the hub is low, and the dynamic pressure near the middle of the ventilator runner is higher.The research results have some advantages for the optimization design of the mining counter-rotating axial flow fan The guiding significance.