CAJ | 학술논문

设计研究中离心压缩机进口均假定为直管,而实际应用中进口管道多为弯管布置。采用数值模拟的方法对比了不同转速下90°进口弯管和进口直管对离心压缩机内部压力脉动的影响,并分析了进口弯管对离心压缩机气动噪声的影响。结果表明,进口弯管引起叶轮进口处基频的8倍频幅值在近弯管内侧处增大,叶片表面的基频幅值减小；叶顶间隙处16倍频幅值显著增大,在扩压器出口处影响已很小。弯管进口造成离心压缩机进口处声压级增大约7dB,需要在气动设计过程中考虑进口弯管的影响且在进口处采取降噪设施,以减少从进口弯管向外辐射的噪声。弯管进口对出口处噪声的影响较小,主要为宽频噪声减小。
설계연구중리심압축궤진구균가정위직관,이실제응용중진구관도다위만관포치。채용수치모의적방법대비료불동전속하90°진구만관화진구직관대리심압축궤내부압력맥동적영향,병분석료진구만관대리심압축궤기동조성적영향。결과표명,진구만관인기협륜진구처기빈적8배빈폭치재근만관내측처증대,협편표면적기빈폭치감소；협정간극처16배빈폭치현저증대,재확압기출구처영향이흔소。만관진구조성리심압축궤진구처성압급증대약7dB,수요재기동설계과정중고필진구만관적영향차재진구처채취강조설시,이감소종진구만관향외복사적조성。만관진구대출구처조성적영향교소,주요위관빈조성감소。
In the design research, the inlet of centrifugal compressor is assumed to be a straight pipe, but the inlet is generally bend pipe in the practical application. The effect of 90° bent pipe and straight pipe on the pressure pulsation of a centrifugal compressor in different speed is numerically simulated, and the influence of the bent pipe on compressor’s aerodynamic noise is analyzed. The result shows that the bent pipe makes the 8th harmonic base fre-quency at impeller inlet increases near the bent pipe inside, the base frequency on the blade decreases, the 16th har-monic base frequency in tip clearance increases observably, the pressure pulsation change little at diffuser outlet. The bent pipe makes the sound pressure level at centrifugal compressor’s inlet increase by about 7dB, which needs to val-ue the inlet bent pipe in the aerodynamic design and reduce the radiation noise from the inlet. The bent pipe has little effect on aerodynamic noise at the outlet, where the broadband noise decreases.