离心通风机气动特性与振动量级关系研究

发布时间：2018-06-30 06:22

本文选题：离心通风机 + 气动激励　；参考：《中国舰船研究院》2017年博士论文

【摘要】：开展离心通风机低噪声设计研究,是国民经济和国防军事相关设备的发展需求,同时也是保护生态环境和可持续发展的战略要求。近十几年来,随着科学技术的发展,在离心通风机的气动性能分析、振动噪声控制等方面都有较大的进展。但是,在取得进展的同时,也仍然存在一些不足,首先,对离心通风机气动激励的产生机理、内部具体分布特性等研究较少;其次,已开展的通风机振动噪声预测及控制措施方面的研究大多集中在流固耦合分析方面,过程复杂、漫长且以目前的手段和研究现状,还存在较大的误差,对目前离心通风机领域多变的实际需求,难以有效快速的提供工程应用指导。气动激励是影响离心通风机振动的最主要因素之一,本文主要以目前工程实际应用需求为出发点,采用流场仿真计算—流场测试验证—振动测试—气动特性与振动关联性分析这一步骤,通过计算和测试分析离心通风机内部气动激励,结合振动测试,直接探索气动因素对离心通风机振动的影响,获得离心通风机振气动特性与振动之间的量级关系,为离心通风机低噪声结构设计及振动预估提供一项简洁的新手段。首先,针对常规结构的离心通风机进行不同湍流模型、网格数目及几何模型处理等方面的计算对比分析,以确定合适的计算模型,为本文计算分析提供有效依据;在此基础上,针对离心通风机叶轮、蜗舌等部件结构等的变化,进行计算对比,从总性能、定常流动方面分析离心通风机局部结构变化对性能的影响,初步分析离心通风机内部流动的激励,为后文结构-气动特性-振动特性的分析提供定性分析的依据;其次,在定常计算分析的基础上,对常规结构离心通风机内部流动进行非定常计算分析,探索离心通风机内部压力脉动产生机理和不同位置的变化规律;在此基础上,以常规结构为基准,进行叶型、蜗舌局部结构变化情况下的压力脉动计算,分析局部结构变化对离心通风机内部气动激励的影响;通过比较标准结构下不同区域和不同结构下对应区域压力脉动的变化情况,初步掌握离心通风机内部气动激励的沿周向和轴向的分布规律以及结构变化对离心通风机内部气动激励的定量影响。在计算分析的基础上,进行常规结构下离心通风机内部流场的测试,通过内部流动、静压分布和压力脉动测试,对比验证计算和试验的有效性;通过计算和测试对比发现,在获得整体规律上计算结果和测试结果基本一致,并且在具体量值上也较为接近(误差在10%)以内,并以此对通风机内部如叶轮进出口、叶片通道等位置的压力分布及脉动进行了进一步分析,为探索结构与气动激励之间的关系提供了更为可靠的依据。最后,进行离心通风机振动测试,通过常规结构样机压力脉动测试值、计算值和振动测试值的对比及关联性分析,进一步获得气动激励对通风机壳体振动的影响以及在此激励下典型位置、典型频率的振动特性;在此基础上,通过不同叶轮结构、不同蜗舌结构典型位置压力脉动计算值和样机对应位置振动测试值的分析,初步总结本文研究这一类离心通风机气动特性与典型位置、典型频率振动的量级关系,为离心通风机低噪声设计提供有效参考。
[Abstract]:The research on the low noise design of centrifugal fan is the development demand of national economy and national defense military related equipment, and it is also the strategic requirement for protecting the ecological environment and sustainable development. In the last decade, with the development of science and technology, there are great progress in the analysis of aerodynamic performance and vibration and noise control of centrifugal fan. However, at the same time, there are still some shortcomings. First, there is little research on the mechanism of aerodynamic excitation and the specific distribution characteristics of the centrifugal fan. Secondly, the research on the prediction and control measures of the ventilator's vibration and noise is mostly focused on the fluid solid coupling analysis, and the process is complicated and long. The former means and the present research situation still have large error. It is difficult to provide engineering application guidance for the changeable actual demand in the field of centrifugal fan. Aerodynamic excitation is one of the most important factors affecting the vibration of centrifugal fan. This paper mainly takes the actual application requirements of the current engineering as the starting point, and adopts the flow field simulation meter. The calculation and verification of the flow field test - the vibration test - the step of the aerodynamic characteristic and the vibration correlation analysis, through the calculation and test analysis of the internal aerodynamic excitation of the centrifugal fan and the vibration test, the influence of the aerodynamic factors on the vibration of the centrifugal fan is explored directly, and the relation between the aerodynamic characteristics of the centrifugal fan and the vibration is obtained. The low noise structure design and vibration prediction of the centrifugal fan provide a simple novice section. Firstly, the calculation and comparison of the different turbulence models for the conventional structure centrifugal fan, the number of grid numbers and the geometric model processing are compared, so as to determine the appropriate calculation model and provide the effective basis for the calculation and analysis of this paper; and this foundation is based on this basis. In view of the changes in the structure of the centrifugal fan impeller and the worm tongue and other components, the influence of the local structure change on the performance of the centrifugal fan is analyzed from the total performance and constant flow, and the internal flow excitation of the centrifugal fan is preliminarily analyzed to provide the qualitative analysis for the analysis of the later structure aerodynamic characteristics vibration characteristics. Secondly, on the basis of the constant calculation and analysis, the unsteady calculation and analysis of the internal flow of the conventional centrifugal fan are carried out, and the mechanism of pressure pulsation and the change of the different positions are explored in the centrifugal fan. On this basis, the pressure pulsation under the normal structure as the base, the moving leaf type and the local structure of the worm tongue is changed. The influence of local structural change on the internal aerodynamic excitation of centrifugal fan is analyzed. By comparing the changes of pressure fluctuation in different regions and different structures under the standard structure, the distribution law of the aerodynamic excitation along the circumferential and axial direction of the centrifugal fan and the change of the structure to the inner of the centrifugal fan are preliminarily studied. On the basis of the calculation and analysis, the internal flow field of the centrifugal fan under the conventional structure is tested. The effectiveness of the calculation and test is verified by the internal flow, the static pressure distribution and the pressure pulsation test. The calculation results and the test results are found to be basic through the calculation and test comparison. In addition, the pressure distribution and pulsation in the ventilator, such as impeller inlet and exit, blade passage, and so on, are further analyzed in order to find a more reliable basis for exploring the relationship between structure and aerodynamic excitation. Finally, the vibration test of centrifugal fan is carried out. According to the pressure fluctuation test value of the conventional prototype, the comparison of calculated value and the vibration test value and the correlation analysis, the influence of the aerodynamic excitation on the vibration of the fan shell and the typical position and the typical frequency vibration characteristics under this excitation are obtained. On this basis, the typical position pressure of different worm tongue structure is passed through different impeller structures. The analysis of the calculation value of the force pulsation and the test value of the corresponding position of the prototype of the prototype, and the preliminary summary of the study on the aerodynamic characteristics of this type of centrifugal fan, the typical position and the magnitude relation of the typical frequency vibration, can provide an effective reference for the low noise design of the centrifugal fan.
【学位授予单位】：中国舰船研究院
【学位级别】：博士
【学位授予年份】：2017
【分类号】：TH432

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