气流脉动与流体动力性噪声诱发机理研究

项目名称： 气流脉动与流体动力性噪声诱发机理研究

项目编号： No.50806055

项目类型： 青年科学基金项目

立项/批准年度： 2009

项目学科： 无线电电子学、电信技术

项目作者： 吴华根

作者单位： 西安交通大学

项目金额： 21万元

中文摘要： 流体动力性噪声是压缩机的主要噪声源，特别是在高转速螺杆压缩机中该类噪声尤为突出，既对环境造成了声污染，又增加了功耗，控制和降低噪声是目前压缩机发展面临的最大技术难点之一。突破这一技术难点的关键基础在于吸、排气腔流场和气流脉动的研究。本项目通过对螺杆压缩机的几何及运行参数、气流脉动、噪声这三者之间的相互作用机理研究，建立螺杆压缩机完善、准确的变质量工作过程数学计算模型，并通过对气流脉动形成机理的研究，建立了气流脉动数学计算模型与压力脉动的传递矩阵。在此基础上，建立了螺杆压缩机热力学工作过程与排气系统气流脉动耦合计算的理论模型，揭示了压缩机几何及运行参数对流场及气流脉动的作用机理。并以此为基础，建立了以lighthill基本方程为基础的声学数值计算模型，有助于理解螺杆压缩机流体动力性噪声的诱发机理。在理论研究的同时，搭建了螺杆压缩机综合性能及气流脉动和噪声试验台，研究了螺杆压缩机几何及运行参数对气流脉动的作用和气流脉动对压缩机性能影响，并对气流脉动与噪声之间的作用机理进行了研究分析。本项目的开展为螺杆压缩机的型线、孔口设计等提供了科学指导，也为开发高效低噪及高转速压缩机奠定了基础。

中文关键词： 螺杆压缩机；气流脉动；噪声；数学模型；试验研究

英文摘要： The major noise of twin-screw compressor comes from fluid dynamic noise, especially in high speed twin screw compressor. It pollutes the environment and consumes the additional energy. So how to control and decrease the noise is proved to be one of the crucial technical difficulties which hinder the development of twin-screw compressor. In order to break this critical technical difficulty, a new integrative mathematical model considering the coupling relationship between the discharged gas pulsation and working process of compressor is built in this project, based on the research on the mechanism of interaction among the structural and operation parameters, gas pulsation and noise of compressor.This new model includes the submodel of working process of compressor, submodel of gas pulsation and the transfer matrix of pressure pulsation. Also it is helpful for comprehending the effect of structural and operation parameters on the flow distribution and gas pulsation of the compressor. For understanding the action mechanism of the noise in twin-screw compressor, an acoustical numerical calculation model is built up on the basis of the acoustic theory of Lighthill. In order to verify the coupling model, a test rig including the measurements of performance, gas pulsation and noise of twin screw compressor has been set up. The experiments that include the research on the effect of structural and operation parameters on the gas pulsation, the effect of gas pulsation on the performance and the interaction mechanism between the gas pulsation and noise have been carried out. Also, the experimental results have been analyzed and compared with the calculation results. It shows that the results of theoretical calculation based on the coupling model are in good agreement with the experimental data, which leads to conclusion that the model can be used as a powerful tool for performance and gas pulsation prediction. The research on this project can not only bring the guides for rotor profile and orifice designing, but also establish the foundation for the development of the high efficiency, lower noise and high operation speed twin screw compressor.

英文关键词： Twin-screw Compressor; Gas Pulsation; Noise; Mathematical Model; Experimental Research