基于振动信号的螺杆压缩机故障诊断仿真研究

发布时间：2018-01-30 02:05

本文关键词： 螺杆压缩机建模仿真模态分析故障特征　出处：《上海交通大学》2015年硕士论文　论文类型：学位论文

【摘要】：随着螺杆压缩机越来越多地作为核心设备在石油化工领域被应用,其运行的可靠性和安全性日益受到人们的重视,螺杆压缩机一旦发生故障,往往造成整个工艺流程的停产,此外如果停机不及时,还会导致阴阳转子“咬死”导致整个主机报废,进行螺杆压缩机的故障诊断研究是非常必要的。为了降低产品的故障率、正确开展预知维修以及降低企业的服务损失,进行螺杆压缩机故障诊断系统的开发也是迫切的。因而本文采用有限元方法建立了螺杆压缩机的转子动力学模型,并对其主要故障的振动特征进行了仿真和实验验证研究,进而获取其故障诊断所需的振动信号故障特征。本文根据螺杆压缩机工作原理和特点,基于ANSYS软件采用有限元方法建立了转子动力学模型,对模型分别进行瞬态响应和稳态响应分析。在分析中重点进行了自由模态和支撑模态的分析,并采用瞬态动力学方法,进行了时变故障激励的加载,通过啮合频率下的简谐激励仿真转子啮合不良故障、啮合频率下的矩形激励仿真转子与机壳碰擦以及旋转频率下的简谐激励仿真不平衡故障,成功获取了上述故障的速度、位移、加速度和支反力的时域响应,此外通过离散傅里叶方法获取了响应的频域图谱;通过对不同频率激励下的系统仿真获取了各故障对频率变化的响应关系。通过对平衡等级、频率、不平衡量下的仿真获取了不平衡故障响应与其的关系。最后首先通过锤击模态法对自由状态下的转子模态进行了验证(验证了一阶固有频率);其次基于LabVIEW编制了螺杆压缩机振动信号采集分析系统,使用该系统采集和分析了阳转子排气端轴承座处的振动信号,分别验证了啮合不良故障、转子和机壳碰擦故障以及不平衡故障,实验结果与仿真结果基本一致,证明了系统建模和仿真的正确性。
[Abstract]:With more and more screw compressor being used as the core equipment in the petrochemical field, people pay more and more attention to the reliability and safety of the screw compressor, once the screw compressor breaks down. Often cause the entire process to stop production, in addition, if the shutdown is not timely, but also lead to the yin-yang rotor "bite", resulting in the entire host scrapped. It is very necessary to study the fault diagnosis of screw compressor. In order to reduce the failure rate of products, correctly carry out predictive maintenance and reduce the service loss of enterprises. It is urgent to develop the fault diagnosis system of screw compressor, so the rotor dynamics model of screw compressor is established by finite element method in this paper. The vibration characteristics of the main faults are studied by simulation and experiment, and the fault characteristics of the vibration signals are obtained. According to the working principle and characteristics of the screw compressor, the vibration characteristics of the main faults are obtained in this paper. Based on ANSYS software, the rotor dynamic model is established by finite element method, and the transient and steady response of the model are analyzed respectively. In the analysis, the free mode and the supporting mode are analyzed. The transient dynamic method is used to load the time-varying fault excitation, and the fault of rotor meshing is simulated by the harmonic excitation under the meshing frequency. The rectangular excitation simulation under meshing frequency is used to simulate the rotor and shell rubbing and the simple harmonic excitation under rotation frequency to simulate the unbalanced fault. The time domain responses of the above faults such as velocity displacement acceleration and supporting reaction force are obtained successfully. In addition, the frequency domain map of the response is obtained by discrete Fourier method. Through the system simulation under different frequency excitation, the response of each fault to the frequency change is obtained. The relationship between the unbalance fault response and the unbalance fault response is obtained by simulation. Finally, the rotor mode in the free state is verified by hammering mode method (verifying the first order natural frequency). Secondly, the vibration signal acquisition and analysis system of screw compressor is programmed based on LabVIEW. The vibration signal of bearing seat at the exhaust end of positive rotor is collected and analyzed by using the system, and the malfunction of meshing is verified respectively. The experimental results are in good agreement with the simulation results, which proves the correctness of the system modeling and simulation.
【学位授予单位】：上海交通大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TE65;TQ051.21

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