【摘要】：包裝用鋼桶具有機械性能優(yōu)良、強度高、成本低、使用方便、加工性能優(yōu)越、綜合防護性能強等特點,廣泛應用于各種工業(yè)與運輸包裝,成為長期保存內(nèi)裝物料的手段。鋼桶的加工已經(jīng)實現(xiàn)了自動化流水線生產(chǎn),然而成品鋼桶的檢測技術(shù)還不成熟,對鋼桶的檢測技術(shù)提出了更高的要求。(1)本文介紹了聲發(fā)射現(xiàn)象產(chǎn)生的機理,闡述了鋼桶泄漏聲發(fā)射信號的檢測原理,分析了聲發(fā)射檢測技術(shù)的特點,介紹了聲發(fā)射信號常用的處理方法,為探究鋼桶泄漏產(chǎn)生聲發(fā)射的機理與實驗研究提供了理論基礎(chǔ)。(2)采用FLUENT有限元分析軟件對鋼桶氣體泄漏射流流場分布情況進行了模擬仿真,選用k-ε湍流模型,建立了鋼桶的泄漏模型,得到了不同內(nèi)壓以及不同漏孔直徑下鋼桶泄漏的仿真結(jié)果,討論了鋼桶泄漏射流速度、壓力等參數(shù)的變化規(guī)律,得到了射流出口處的聲場特征。(3)利用ANSYS Workbench軟件的瞬態(tài)動力學模塊,分析了鋼桶氣體泄漏流固耦合作用下流激振動結(jié)構(gòu)響應情況。建立了鋼桶泄漏流體域和結(jié)構(gòu)域模型,設(shè)定了合適的網(wǎng)格尺寸和時間步長,得到了不同鋼桶內(nèi)壓以及漏孔直徑下結(jié)構(gòu)激勵響應,討論了鋼桶漏孔處應力強度、軸向振動位移、流體泄漏速度等參數(shù)的分布情況,以及各參數(shù)隨鋼桶內(nèi)壓和泄漏孔直徑的變化情況。根據(jù)仿真結(jié)果可知,鋼桶漏孔直徑對鋼桶漏孔處質(zhì)點的應力強度、軸向振動位移和流體的泄漏速度的影響較小,鋼桶內(nèi)壓的變化對其影響較明顯。但是,不論是泄漏孔徑還是內(nèi)壓的變化對各參量的特征頻率與峰值頻率影響甚微。(4)最后,通過實驗分析了鋼桶氣體泄漏聲發(fā)射信號的特征量和特征頻率的規(guī)律,探討了漏孔直徑、內(nèi)壓與鋼桶泄漏特征參數(shù)的相關(guān)性,并結(jié)合頻域分析,得到了能夠表征鋼桶泄漏的特征參數(shù)與特征激振頻率。本文利用仿真模擬與現(xiàn)場實驗檢測的方法研究了鋼桶泄漏的激振聲場特征,兩者分別得到了鋼桶泄漏流激振動結(jié)構(gòu)響應的頻譜和峰值頻率。研究結(jié)果表明:實驗與仿真鋼桶泄漏的激振頻譜和峰值頻率基本一致,鋼桶泄漏聲發(fā)射信號產(chǎn)生機理仿真及其實驗研究,為鋼桶氣體泄漏在線檢測技術(shù)的研究提供了依據(jù)。
[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.
【學位授予單位】：南通大學
【學位級別】：碩士
【學位授予年份】：2014
【分類號】：TB486

【參考文獻】

相關(guān)期刊論文 前1條

1 李曉東;江e，

本文編號：2244390