Investigation On Diffuser Effect On Centrifugal Compressor Performance And Radiated Noise

With the industrial development today, compressors are widely used in steel, shipbuilding, petroleum, automotive, aerospace, and many other areas. Visibly compressor has been occupied an important position. In the using process of compressor, its performance requirements of people are more and more high, and the noise problems of vibration and radiation receive much more attention. Diffuser is an important part in the compressor, the different type of diffuser will lead to the difference of performance and vibration noise of the compressor. In this paper, based on simulation and experiment, the mechanism of impact of diffuser on performance and radiated noise of compressor are studied to find the source of vibration and noise of compress. That has very important significance to improve compressor performance, reduce noise and improve people’s environment quality of work and life.In this paper, the MCL series centrifugal compressors of Shenyang Blower Group are for the research. Based on the study of simulation calculation and analysis of impeller, the flow field of different types of diffuser of centrifugal compressor is studied. The total pressure distribution of flow field is obtained by calculation. Through performance test, noise test and radiated noise fast prediction test of compressor and a series of tests, the influence of different types of diffuser on performance and radiated noise of compressor are studied.The specific tasks of study are as follows:(l)Simulation analysis of impeller. Internal flow field of diffuser in different shapes of model stage centrifugal compressor is analyzed. The total pressure distribution of the internal flow field of four different types of diffuser is obtained by CFD calculation. Change flow conditions and contrast the performance curves of four different types of diffuser.(2) The tests were implemented to research the compressor performance with the impacts of different diffusers. According to the performing effects both of the compressor with the different diffusers and model stage impacted by the different diffusers especially, performance tests of the stage were implemented, and the performing effects effected the pressure pulsation were analyzed. The pressure pulsation values of impeller inlet, diffuser inlet and the diffuser outlet of compressor and vibration data of enclosure and pipeline were collected, analyzed and compared. The influence on internal pressure pulsation and vibration of the pipeline and the enclosure while the compressor in operation is main considered.(3)Analysis for vibration noise impact of diffuser. Take noise test on compressor installing different diffusers and make correlation processing on acoustic pressure signal. Compare the effects on the compressor noise of different diffusers according to processing results. The determination of the noise source can control the noise and provide effective data support for the design and improvement of compressor. (4)The fast prediction of radiated noise. The MCL series centrifugal compressors of Shenyang Blower Group are for the research. Through a multiple sets of noise tests on compressor, the relationship between the compressor noise and its working parameters are studied, and the experience formula of the noise prediction is found. Determining the main noise source of the compressor, making simulation predictions and improving design to achieve the purpose of controlling noise.