安全阀反冲效应的控制方法研究

发布时间：2018-05-30 03:01

本文选题：安全阀 + 反冲效应　；参考：《华南理工大学》2011年硕士论文

【摘要】：安全阀作为工业装备上的安全保护装置,其作用是防止各种承压设备的内压升高到超过允许的压力值而发生突发性事故,保障设备长期运行,通常作为系统最终保护装置。从安全阀的运行经验可知,安全阀在使用过程中会出现各种各样的故障,如整定压力随着使用时间的推移会发生某些偏差,或者造成泄漏,阀瓣受粘,弹簧刚度过硬或软化,阀杆不对中等原因,从而引起严重的后果。自20世纪80年代开始,人们对安全阀进行了新一轮的研究。从安全阀的动力学特性分析可知,安全阀核心受力部位是阀瓣,但反冲盘在开启时也承受巨大的冲击力,它的反冲效应对阀瓣的开启具有很大作用。于是,对安全阀反冲盘反冲效应的研究非常重要。但是到目前为止,很少有公开发表的文献探讨和研究这个问题。本文主要对安全阀开启过程中超压介质气体在泄放流道中高速流动和转向所产生推举效应,即反冲效应进行研究,采用理论和实验并举的方法来分析计算反冲效应的大小,包括反冲力的数值模拟、反冲力的检测以及反冲效应的计算,从而实现反冲效应的定量化,最后寻找其影响因素并研究如何控制反冲效应的大小。在理论上,采用数值模拟分析软件CFX对反冲力进行动态数值模拟。在实验研究中,结合安全阀在线检测系统,首先得到上下阀瓣的压力检测曲线,再通过反冲效应的物理意义得到全开启过程的反冲力曲线,实验结果和模拟结果进行比较,验证方法的合理性。最后在数值模拟的基础上寻找影响反冲效应的因素,并通过改变这些影响因素来研究如何控制反冲效应。通过实验和模拟计算得到反冲力大小和寻找反冲效应的影响因素可以分析反冲效应大小对阀瓣工作稳定性的影响,对安全阀的改造和设计具有重要的意义。分析的结果表明数值模拟计算的方法是合理的,下调节圈的位置、反冲盘凸边长度和弹簧刚度对反冲效应有很大影响,可通过改变它们来控制反冲效应的大小,进而提高安全阀的工作稳定性。
[Abstract]:As a safety protection device in industrial equipment, the safety valve can prevent the internal pressure of various kinds of pressure equipment from rising to exceed the allowable pressure value and cause sudden accidents, and ensure the equipment to run for a long time, usually as the final protection device of the system. From the operation experience of the safety valve, it can be seen that there will be various failures in the use of the safety valve, such as certain deviation of the setting pressure over time, or leakage, adhesion to the disc, stiffness of the spring, or softening. Stem is not medium cause, causing serious consequences. Since 1980's, people have carried on a new round of research on safety valve. From the analysis of the dynamic characteristics of the relief valve, it can be seen that the core force of the relief valve is the disc, but the recoil disc also bears a great impact when it is opened, and its recoil effect plays a great role in the opening of the disc. Therefore, it is very important to study the recoil effect of relief valve recoil disc. But so far, few published literature have explored and studied this issue. In this paper, the pushing effect of overpressure medium gas flowing and steering at high speed in the outlet of relief valve is studied, that is, backflushing effect, which is analyzed and calculated by both theory and experiment. It includes the numerical simulation of backflushing, the detection of backflushing and the calculation of recoil effect, so as to realize the quantification of recoil effect. Finally, we find out the influencing factors and study how to control the magnitude of recoil effect. In theory, a numerical simulation software CFX is used to simulate the backstroke. In the experimental study, combined with the safety valve on-line detection system, the pressure detection curve of the upper and lower disc is obtained first, and then, through the physical meaning of the backflushing effect, the recoil force curve of the whole open process is obtained. The experimental results are compared with the simulation results. The rationality of the method is verified. Finally, based on the numerical simulation, the factors affecting recoil effect are found, and how to control recoil effect is studied by changing these factors. By means of experiments and simulation, the influence factors of recoil force and searching for recoil effect can be analyzed, which is of great significance to the reconstruction and design of safety valve. The results show that the numerical simulation method is reasonable. The position of the lower regulating coil, the length of the convex edge of the recoil disk and the spring stiffness have great influence on the recoil effect, which can be controlled by changing them. Thus, the working stability of the safety valve is improved.
【学位授予单位】：华南理工大学
【学位级别】：硕士
【学位授予年份】：2011
【分类号】：TH134

【引证文献】