流体引起的空调管路振动分析与实验研究

Analysis and test for fluid flow induced vibration of air conditioner pipes

结合流体动力学和结构动力学分析了空调室外机管路系统由流体引起的振动问题。采用有限元方法建立了管路系统的动力学模型,并通过模态试验验证了模型的准确性。使用流体动力学方法分析了管内流场,获得管道内壁的表面压力,并以压力作为激励,结合实验验证后的管路动力学模型进行了谐响应分析。通过管路ODS(Operational Deflection Shapes)实验,验证了由流体引起的管路振动分析方法的可靠性和有效性。研究表明:管路理论模态分析与实验结果基本吻合,确保建立的动力学模型的准确性,为后续分析的准确度提供了基础;管路振动分析与ODS实验对比结果在低频段理论与实验吻合较好,而在高频段误差较大。分析了误差产生的原因,为后续研究指明了方向。

Pipes connecting compressor and heat exchange coils play an important role in noise and vibration control of air conditioners. The vibration of pipes caused by fluid flow was analyzed with fluid dynamics and structural dynamics. The accurate FE dynamic model of the pipe system was established and the correctness of the FE model was verified using modal analysis and tests. The pressures on the pipe surface were obtained with the fluid dynamic analysis.The excitations（ the pressures） were combined with the FE model verified with tests to analyze harmonic vibration responses of the pipes. Then,the pipes＇ operational deflection shapes（ ODS） test was performed to verify the reliability and effectiveness of the analysis method for fluid flow induced vibration of pipes of air conditioner. The results showed that the results of the pipe system＇s theoretical modal analysis agree well with those of tests to ensure the correctness of the FE dynamic model and to lay a foundation for further analysis; the theoretical analysis results of the pipe system vibration agree better with the results of its ODS test in lower frequency range,but there are larger errors in higher frequency range.The reasons to cause errors were analyzed,they provided a reference for further study.