钢桶气体泄漏声发射信号分析与检测
发布时间：2018-09-15 20:12
【摘要】：包装用钢桶具有机械性能优良、强度高、成本低、使用方便、加工性能优越、综合防护性能强等特点,广泛应用于各种工业与运输包装,成为长期保存内装物料的手段。钢桶的加工已经实现了自动化流水线生产,然而成品钢桶的检测技术还不成熟,对钢桶的检测技术提出了更高的要求。(1)本文介绍了声发射现象产生的机理,阐述了钢桶泄漏声发射信号的检测原理,分析了声发射检测技术的特点,介绍了声发射信号常用的处理方法,为探究钢桶泄漏产生声发射的机理与实验研究提供了理论基础。(2)采用FLUENT有限元分析软件对钢桶气体泄漏射流流场分布情况进行了模拟仿真,选用k-ε湍流模型,建立了钢桶的泄漏模型,得到了不同内压以及不同漏孔直径下钢桶泄漏的仿真结果,讨论了钢桶泄漏射流速度、压力等参数的变化规律,得到了射流出口处的声场特征。(3)利用ANSYS Workbench软件的瞬态动力学模块,分析了钢桶气体泄漏流固耦合作用下流激振动结构响应情况。建立了钢桶泄漏流体域和结构域模型,设定了合适的网格尺寸和时间步长,得到了不同钢桶内压以及漏孔直径下结构激励响应,讨论了钢桶漏孔处应力强度、轴向振动位移、流体泄漏速度等参数的分布情况,以及各参数随钢桶内压和泄漏孔直径的变化情况。根据仿真结果可知,钢桶漏孔直径对钢桶漏孔处质点的应力强度、轴向振动位移和流体的泄漏速度的影响较小,钢桶内压的变化对其影响较明显。但是,不论是泄漏孔径还是内压的变化对各参量的特征频率与峰值频率影响甚微。(4)最后,通过实验分析了钢桶气体泄漏声发射信号的特征量和特征频率的规律,探讨了漏孔直径、内压与钢桶泄漏特征参数的相关性,并结合频域分析,得到了能够表征钢桶泄漏的特征参数与特征激振频率。本文利用仿真模拟与现场实验检测的方法研究了钢桶泄漏的激振声场特征,两者分别得到了钢桶泄漏流激振动结构响应的频谱和峰值频率。研究结果表明:实验与仿真钢桶泄漏的激振频谱和峰值频率基本一致,钢桶泄漏声发射信号产生机理仿真及其实验研究,为钢桶气体泄漏在线检测技术的研究提供了依据。
[Abstract]:The packing steel barrel has the characteristics of excellent mechanical properties, high strength, low cost, convenient use, superior processing performance and strong comprehensive protective performance. It has been widely used in various industrial and transportation packaging, and has become a means of long-term preservation of internal materials. The processing of steel barrel has already realized the automatic assembly line production, but the detection technology of finished steel barrel is not mature, so it puts forward higher requirements for the detection technology of steel barrel. (1) the mechanism of acoustic emission phenomenon is introduced in this paper. The principle of acoustic emission signal detection for steel barrel leakage is described, the characteristics of acoustic emission detection technology are analyzed, and the common processing methods of acoustic emission signal are introduced. It provides a theoretical basis for exploring the mechanism and experimental study of acoustic emission in steel barrel leakage. (2) the flow field distribution of gas leakage jet in steel barrel is simulated by using FLUENT finite element analysis software, and the k- 蔚 turbulence model is selected. The leakage model of steel barrel is established, and the simulation results of steel barrel leakage under different internal pressure and different hole diameter are obtained. The variation law of parameters such as velocity and pressure of leakage jet is discussed. The characteristics of the acoustic field at the jet outlet are obtained. (3) using the transient dynamic module of the ANSYS Workbench software, the fluid-induced vibration structure response under the fluid-solid coupling of the steel barrel gas leakage is analyzed. The model of leakage fluid domain and structure domain of steel barrel is established, the appropriate mesh size and time step are set up, the structure excitation response under different internal pressure of steel barrel and the diameter of leak hole is obtained, and the stress intensity and axial vibration displacement at the leak hole of steel barrel are discussed. The distribution of the fluid leakage velocity and the variation of the parameters with the internal pressure of the steel barrel and the diameter of the leak hole. According to the simulation results, the diameter of steel barrel leak hole has little effect on the stress intensity, axial vibration displacement and fluid leakage velocity, and the change of internal pressure of steel barrel has a more obvious effect on the stress intensity, axial vibration displacement and fluid leakage velocity. However, the variation of leakage aperture or internal pressure has little effect on the characteristic frequency and peak frequency of each parameter. (4) finally, the characteristic quantity and characteristic frequency of acoustic emission signal of gas leakage from steel barrel are analyzed by experiments. The correlation between leak diameter, internal pressure and characteristic parameters of steel barrel leakage is discussed. Combining with frequency domain analysis, the characteristic parameters and the characteristic exciting frequency of steel barrel leakage are obtained. In this paper, the acoustic field characteristics of steel bucket leakage are studied by means of simulation and field experiment. The frequency spectrum and peak frequency of the structural response of steel bucket leakage flow induced vibration are obtained respectively. The results show that the exciting spectrum and peak frequency of steel barrel leakage are basically the same as that of simulation. The simulation of acoustic emission signal generation mechanism and the experimental study provide a basis for the research of on-line detection technology of steel barrel gas leakage.
【学位授予单位】：南通大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TB486
[Abstract]:The packing steel barrel has the characteristics of excellent mechanical properties, high strength, low cost, convenient use, superior processing performance and strong comprehensive protective performance. It has been widely used in various industrial and transportation packaging, and has become a means of long-term preservation of internal materials. The processing of steel barrel has already realized the automatic assembly line production, but the detection technology of finished steel barrel is not mature, so it puts forward higher requirements for the detection technology of steel barrel. (1) the mechanism of acoustic emission phenomenon is introduced in this paper. The principle of acoustic emission signal detection for steel barrel leakage is described, the characteristics of acoustic emission detection technology are analyzed, and the common processing methods of acoustic emission signal are introduced. It provides a theoretical basis for exploring the mechanism and experimental study of acoustic emission in steel barrel leakage. (2) the flow field distribution of gas leakage jet in steel barrel is simulated by using FLUENT finite element analysis software, and the k- 蔚 turbulence model is selected. The leakage model of steel barrel is established, and the simulation results of steel barrel leakage under different internal pressure and different hole diameter are obtained. The variation law of parameters such as velocity and pressure of leakage jet is discussed. The characteristics of the acoustic field at the jet outlet are obtained. (3) using the transient dynamic module of the ANSYS Workbench software, the fluid-induced vibration structure response under the fluid-solid coupling of the steel barrel gas leakage is analyzed. The model of leakage fluid domain and structure domain of steel barrel is established, the appropriate mesh size and time step are set up, the structure excitation response under different internal pressure of steel barrel and the diameter of leak hole is obtained, and the stress intensity and axial vibration displacement at the leak hole of steel barrel are discussed. The distribution of the fluid leakage velocity and the variation of the parameters with the internal pressure of the steel barrel and the diameter of the leak hole. According to the simulation results, the diameter of steel barrel leak hole has little effect on the stress intensity, axial vibration displacement and fluid leakage velocity, and the change of internal pressure of steel barrel has a more obvious effect on the stress intensity, axial vibration displacement and fluid leakage velocity. However, the variation of leakage aperture or internal pressure has little effect on the characteristic frequency and peak frequency of each parameter. (4) finally, the characteristic quantity and characteristic frequency of acoustic emission signal of gas leakage from steel barrel are analyzed by experiments. The correlation between leak diameter, internal pressure and characteristic parameters of steel barrel leakage is discussed. Combining with frequency domain analysis, the characteristic parameters and the characteristic exciting frequency of steel barrel leakage are obtained. In this paper, the acoustic field characteristics of steel bucket leakage are studied by means of simulation and field experiment. The frequency spectrum and peak frequency of the structural response of steel bucket leakage flow induced vibration are obtained respectively. The results show that the exciting spectrum and peak frequency of steel barrel leakage are basically the same as that of simulation. The simulation of acoustic emission signal generation mechanism and the experimental study provide a basis for the research of on-line detection technology of steel barrel gas leakage.
【学位授予单位】：南通大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TB486
【参考文献】
相关期刊论文 前1条
1 李晓东;江e，
本文编号：2244390
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