基于结构适应的离心压缩机自愈调控方法研究

发布时间：2018-08-12 18:06

【摘要】：离心压缩机作为核心设备广泛应用于石油天然气、大型煤化工以及深海油气开采等领域。离心压缩机性能的高低直接影响整套装置经济效益，安全运行以及可靠性。现阶段随着经济快速发展，资源消耗、环境恶化等问题日趋严重。所以如何保持压缩机安全稳定高效运行，提高其设计、运行效率及自愈能力，拓宽工况范围越来越受到广泛的关注。本文针对以上难点和热点应用数值分析方法开发高效精确的分析预测模型，首先对离心压缩机进行非定常数值模拟深入研究了入口导叶与叶轮的非定常相干现象。分析了这种现象对叶轮结构强度的影响，得出这种现象产生气流激振力为造成叶轮叶片断裂故障的主要原因。其次，，探讨了叶轮盖侧曲率及轴向长度对压缩机整级性能影响。对四种不同盖侧曲率叶轮进行气动性能、力学性能以及振动模态综合分析。分析结果表明，减少叶轮轮盖侧曲率会使空气动力学性能明显提高同时也会使叶轮机械性能有所改善，振动固有频率有所提高，但在得益的同时必须要考虑这种叶轮引起相关转子动力学问题。最后，采用CFD技术研究离心压缩机整级性能优化设计方法。应用全三维流场分析的方法分析叶轮、扩压器以及回流器叶片参数变化对压缩机性能的影响。在此基础上，对主要几何参数进行了优化设计并建立气动参数与结构参数之间的对应关系。研究结果表明，通过在压缩机运行过程中调节扩压器叶片的角度，可以使压缩机的最大效率和工况范围均得到改善。对于本模型的压缩机，效率可提高2％以上。优化设计后压缩机整级气动性能得到明显改善。本文的研究成果可为提高压缩机的设计效率和工况范围及自愈调控提供有效的方法。
[Abstract]:Centrifugal compressor as the core equipment is widely used in oil and gas, large-scale coal chemical industry, deep-sea oil and gas mining and other fields. The performance of centrifugal compressor directly affects the economic benefit, safe operation and reliability of the whole unit. At present, with the rapid development of economy, resources consumption, environmental deterioration and other problems are becoming more and more serious. Therefore, how to keep compressor safe, stable and efficient operation, improve its design, operation efficiency and self-healing ability, broaden the scope of working conditions has been more and more widely concerned. In this paper, an efficient and accurate analysis and prediction model is developed by using the numerical analysis method in view of the above difficulties and hot spots. First, the unsteady coherent phenomenon between the inlet guide vane and the impeller is deeply studied by unsteady numerical simulation of the centrifugal compressor. The influence of this phenomenon on the strength of impeller structure is analyzed. It is concluded that the main reason for the failure of impeller blade is the airflow exciting force caused by this phenomenon. Secondly, the influence of the side curvature and axial length of the impeller cover on the overall performance of the compressor is discussed. The aerodynamic, mechanical and vibration modes of four kinds of impellers with different cover and side curvature were analyzed. The results show that reducing the lateral curvature of the impeller cover can obviously improve the aerodynamic performance and improve the mechanical properties of the impeller and the natural frequency of vibration. But at the same time, the rotor dynamics caused by the impeller must be considered. Finally, CFD technology is used to study the optimization design method of centrifugal compressor integral performance. The effect of blade parameters of impeller diffuser and reflux on compressor performance was analyzed by using the method of full-3D flow field analysis. On this basis, the main geometric parameters are optimized and the corresponding relationship between aerodynamic parameters and structural parameters is established. The results show that the maximum efficiency and working range of the compressor can be improved by adjusting the angle of the diffuser blade during the operation of the compressor. For the compressor of this model, the efficiency can be increased by more than 2%. After the optimization design, the overall aerodynamic performance of the compressor is obviously improved. The research results of this paper can provide an effective method for improving the design efficiency, working condition range and self-healing regulation of compressor.
【学位授予单位】：北京化工大学
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：TH452

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