压力容器爆破压力数值模拟与试验研究

发布时间：2018-03-17 06:00

本文选题：压力容器　切入点：爆破压力　出处：《浙江工业大学》2015年硕士论文　论文类型：学位论文

【摘要】：压力容器内部储存着大量的能量,一旦过载引发爆破,后果是灾难性的。精确的爆破压力计算不仅可以保证容器安全的运行,还能减少材料的浪费。压力容器爆破压力的常用分析方法可分为理论计算、试验测量和数值模拟等三种。理论计算方法通过理论推导求得压力容器爆破压力的计算公式,因材料的非线性和容器几何结构复杂性给求解解析解带来了很大困难,因此仅适用于圆柱壳或球壳等简单结构容器。试验测量方法一般需要进行大量实际容器爆破试验,根据试验结果拟合爆破压力计算公式,因此成本很高,而且试验结果还受制造精度的影响。数值模拟根据容器的实际结构建立模型,采用材料真实的本构关系计算容器的爆破压力,是一种简便高效的方法。特别是对于带接管压力容器,目前还没有一种有效的爆破压力计算方法,本文通过数值模拟和试验研究相结合的方法,提出容器的爆破压力计算公式,研究结果具有重要的理论意义和工程应用价值。本文首先总结了常用的爆破压力计算公式,分析了现有计算公式的局限性。通过拉伸试验得到材料的真实本构模型,采用弹塑性分析法,进行大量不同结构的压力容器爆破压力数值模拟计算,拟合得到同时适用于不带接管和带接管容器的爆破压力计算公式。论文的主要研究工作和成果如下:(1)通过拉伸试验得到的材料真实应力和真实应变关系,建立基于多线性等向强化的材料本构模型。采用弹塑性分析法,进行压力容器爆破压力数值模拟计算,得到导致总体结构不稳定的塑性垮塌载荷,即爆破压力。(2)比较三台容器的爆破压力数值模拟和爆破试验结果,发现两者吻合较好,验证了爆破压力数值模拟方法的可靠性。从容器爆破的位置来看,不带接管容器最大应变位置出现在筒体中间位置,而带接管容器最大应变位于接管与筒体连接处,其结果与爆破试验的爆破位置一致。(3)常用的爆破压力计算公式包括:中径公式、福贝尔公式、史文逊公式和Cloud公式,与数值模拟方法相比,对于不带接管的容器,两者的计算精度基本相当;但对于带接管的容器,采用数值模拟计算的爆破压力误差明显小于常用公式计算误差。(4)采用数值模拟方法研究了长径比对爆破压力的影响。当长径比较小时,封头对筒体的加强作用显著,爆破压力随长径比增大而降低;当长径比较大时,封头对筒体几乎没有加强作用,爆破压力不随长径比变化。(5)分析了带接管容器的开孔参数对爆破压力的影响规律。结果发现,容器爆破压力随着开孔率的增大而逐渐降低,随着接管与筒体厚度比的增加而明显升高。(6)通过大量爆破压力数值模拟数据拟合,得到了综合考虑长径比和接管开孔系数等参数的碳钢容器爆破压力计算公式。该经验公式同时适用于不带接管和带接管容器的爆破压力计算。
[Abstract]:Pressure inside the container to store a lot of energy, once the overload caused by blasting, the consequences are disastrous. Not only can guarantee the safe operation of the container the exact calculation of the blasting pressure, but also reduce the waste of material. Common methods for analysis of pressure vessel explosion pressure can be divided into theoretical calculation, experimental measurement and numerical simulation of three kinds of calculation. The theoretical formula calculation method of pressure vessel pressure blasting obtained through theoretical derivation, because of difficult nonlinear and complex geometric structure of the container material to solve the analytical solution, so it only applies to a cylindrical shell or shell structures and vessels. The test methods generally require a number of actual vessel blasting test according to the test results, the calculation formulas the blasting pressure, so the cost is very high, and the test results are affected by the manufacturing precision of the numerical simulation. According to the actual structure of container construction formwork The container type, calculation of material constitutive relation of the real burst pressure, is a simple and efficient method. Especially for pressure vessel with nozzle, there is not a effective blasting pressure calculation method, method of combining numerical simulation and experimental research, the proposed formula of blasting pressure vessel, research the results have important theoretical significance and engineering application value. This paper summarizes the commonly used blasting pressure calculation formula, analyzes the limitation of the existing formula. Through the tensile test of real material constitutive model, adopting elastic-plastic analysis method to simulate a large number of different structure of pressure vessel pressure blasting numerical fitting at the same time for without taking over and over with the calculation formula of blasting pressure vessel. The main research work and results are as follows: (1) through the tensile test True stress and true strain relationship, establish multi linear based on reinforcement constitutive model. The elasto-plastic analysis method, numerical simulation of blasting pressure of the pressure vessel, has led to the plastic collapse load of the overall structure is not stable, namely the blasting pressure. (2) comparison of three vessels numerical simulation burst pressure and test results, found in good agreement, to verify the reliability of the numerical simulation method of blasting pressure. From the container blasting position, do not take over the position of the maximum strain in the middle position of the cylinder container, and take over the maximum strain of container is located at the joint of nozzle and cylinder, and the results of blasting blasting the same position. (3) the formula including the calculation of the normal blasting pressure formula, Faubert formula, history Wenxun formula and Cloud formula, compared with the numerical simulation method for container with nozzles, The calculation accuracy of both are similar; but for the container with nozzle, numerical simulation of blasting pressure calculation error is significantly less than the commonly used formula. (4) the influence of slenderness ratio on the blasting pressure numerical simulation method. When the length diameter is small, strengthening the role of head of the cylinder body is significant, with the blasting pressure the ratio of length to diameter decreases; when the aspect ratio is larger, the head of the cylinder body almost no strengthening effect. Blasting pressure does not vary with the ratio of length to diameter change. (5) analyzed the law of the opening of the container with nozzle hole parameters influence on blasting pressure. The results showed that the blasting pressure vessel and gradually reduce with the increase of hole the rate, with the increase of the pipe and the cylinder thickness ratio increased. (6) through lots of numerical simulation of blasting pressure data fitting, by considering the slenderness ratio and the parameters of nozzle opening pressure coefficient of the Tan Gangrong is blasting The formula. The empirical formula is also applicable to the calculation of blasting pressure without the nozzle and the nozzle with the nozzle.

【学位授予单位】：浙江工业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TH49

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