Pressure pulsation analysis during rotational stall stage of multiwing centrifugal fan
PAN Zhongyong， CHEN Jiahao， ZHANG Shuai
1. National Engineering Research Center for Pumps and Systems, Jiangsu University, Zhenjiang， Jiangsu 212013, China； 2. Wuxi Mingheng Hybrid Technology Co., Ltd., Wuxi， Jiangsu 214000, China
Abstract：To investigate the pressure pulsation characteristics of multiwing centrifugal fans in the rotational stall stage, taking the multiwing centrifugal fans as research object, the Creo software was used to model in three dimensions, and the models were meshed and calculated for unsteady values. Monitoring points were set in different circumferential, radial and axial positions of the impeller outlet, and the internal pressure pulsation law of the fan under the rotational stall condition was analyzed. The calculation results show that the pressure coefficient of the monitoring point at the diaphragm tongue is the largest, and with the decreasing of flow, the intensity of pressure pulsation is increased. The impeller outlet is affected by the dynamic and static interference between impeller and volute, and the amplitude of the pressure coefficient is the largest. When it moves radially to the volute wall, the pressure pulsation degree is weakened. The law of pressure pulsation is slightly affected by the axial position change，while the change of rotational stall degree can cause the change of pressure pulsation. The stronger the rotational stall is, the more intense the pressure pulsation is. The wider the lowfrequency pulsation range is, the higher the stall frequency amplitude is.
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