Numerical Simulation And Experimental Study Of Burst Pressure Of Pressure Vessel

There is a great amount of energy stored in the pressure vessel, and the consequences are catastrophic once the overload is triggered. Accurate burst pressure calculation can not only ensure the safe operation of the vessel, but also reduce the waste of materials.The common analysis method of pressure vessel burst pressure can be divided into three kinds, theoretical calculation, experimental measurement and numerical simulation. The theor-etical calculation method is derived from the theoretical derivation of the calculation formula of pressure vessel burst pressure. Because of the material nonlinearity and the complexity of container geometry, it is very difficult to solve the analytical solution. Therefore, it is only suitable for the simple structure, such as cylindrical shell and spherical shell. Test methods generally need to carry out a large number of actual vessel blasting test, according to the experimental results to fit the blasting pressure calculation formula, the cost is very high, and the test results are also affected by the manufacturing precision. Numerical simulation is a simple and efficient method, which is based on the actual structure of the container to establish the model and use of the real stress strain relationship to calculate the pressure of the vessel. Especially for pressure vessel with tube, there is no effective method to calculate the pressure. By means of numerical simulation and experimental research, the paper puts forward the calculation formula of pressure vessel burst pressure. The results have important theoretical significance and engineering application value. This paper first summarizes the commonly used burst pressure calculation formula and analyzes the limitations of the existing calculation formula. The real constitutive model of the material was tensile test. Through the elastic plastic method, the numerical simulation of the explosion pressure of a large number of containers is carried out, and the calculation formula of burst pressure is applied to the pressure vessel with tube or without tube at the same time.The main research work and achievements of this paper are as follows:(1) The relationship between real stress and strain of the material was obtained by tensile test, and the constitutive model based on multi linear and istropic hardening is established. The failure of the pressure vessel is simulated by using the elastic plastic analysis method, and get to the plastic collose of structural instability, namely burst pressure.(2) The numerical simulation and the experimental results of the explosion pressure of three test containers are compared. The results show that the reliability of the numerical simulation method is verified. From the location of the container, the maximum strain position of the container is located in the middle position of the cylinder, and the maximum strain of the vessel is located at the junction of the tube.(3) Commonly used burst pressure formula includes: Middle diameter formula, Faupel formula, Svensson formula and Cloud formula. Compared with the numerical simulation method, the calculation accuracy of the two mathods is basically equivalent for cylindrical vessels, but for the vessel with nozzle, the pressure error of numerical simulation is obviously less than that of common formula.(4) The influence of length to diameter ratio on burst pressure is studied by using numerical simulation method. When the length to diameter ratio is small, the reinforcing effect of the head on the cylinder is significant. The burst pressure decreases with the increase of the length to diameter ratio. When the length to diameter ratio is large, the head has little effect on the cylinder.(5) The influence of the parameters of the open hole parameters on the explosion pressure is analyzed. The results show that the burst pressure of the pressure vessel is gradually decreased with the increase of the opening rate, and significantly higher with the increase of thickness ratio.(6) By means of a large number of numerical simulation data fitting, the calculation formula of the explosive pressure of carbon steel vessel with the length diameter ratio and the open hole coefficient is obtained. The empirical formula is suitable for the calculation of the blasting pressure of pressure vessel with tube or without tube.