本文選題：安全閥 + 反沖效應�。� 參考：《華南理工大學》2011年碩士論文

【摘要】：安全閥作為工業(yè)裝備上的安全保護裝置,其作用是防止各種承壓設備的內(nèi)壓升高到超過允許的壓力值而發(fā)生突發(fā)性事故,保障設備長期運行,通常作為系統(tǒng)最終保護裝置。從安全閥的運行經(jīng)驗可知,安全閥在使用過程中會出現(xiàn)各種各樣的故障,如整定壓力隨著使用時間的推移會發(fā)生某些偏差,或者造成泄漏,閥瓣受粘,彈簧剛度過硬或軟化,閥桿不對中等原因,從而引起嚴重的后果。自20世紀80年代開始,人們對安全閥進行了新一輪的研究。從安全閥的動力學特性分析可知,安全閥核心受力部位是閥瓣,但反沖盤在開啟時也承受巨大的沖擊力,它的反沖效應對閥瓣的開啟具有很大作用。于是,對安全閥反沖盤反沖效應的研究非常重要。但是到目前為止,很少有公開發(fā)表的文獻探討和研究這個問題。 本文主要對安全閥開啟過程中超壓介質(zhì)氣體在泄放流道中高速流動和轉(zhuǎn)向所產(chǎn)生推舉效應,即反沖效應進行研究,采用理論和實驗并舉的方法來分析計算反沖效應的大小,包括反沖力的數(shù)值模擬、反沖力的檢測以及反沖效應的計算,從而實現(xiàn)反沖效應的定量化,最后尋找其影響因素并研究如何控制反沖效應的大小。在理論上,采用數(shù)值模擬分析軟件CFX對反沖力進行動態(tài)數(shù)值模擬。在實驗研究中,結(jié)合安全閥在線檢測系統(tǒng),首先得到上下閥瓣的壓力檢測曲線,再通過反沖效應的物理意義得到全開啟過程的反沖力曲線,實驗結(jié)果和模擬結(jié)果進行比較,驗證方法的合理性。最后在數(shù)值模擬的基礎上尋找影響反沖效應的因素,并通過改變這些影響因素來研究如何控制反沖效應。通過實驗和模擬計算得到反沖力大小和尋找反沖效應的影響因素可以分析反沖效應大小對閥瓣工作穩(wěn)定性的影響,對安全閥的改造和設計具有重要的意義。 分析的結(jié)果表明數(shù)值模擬計算的方法是合理的,下調(diào)節(jié)圈的位置、反沖盤凸邊長度和彈簧剛度對反沖效應有很大影響,可通過改變它們來控制反沖效應的大小,進而提高安全閥的工作穩(wěn)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.
【學位授予單位】：華南理工大學
【學位級別】：碩士
【學位授予年份】：2011
【分類號】：TH134

【引證文獻】

相關碩士學位論文 前1條

1 戴芳芳;安全閥反沖效應的數(shù)值模擬與實驗研究[D];華南理工大學;2012年

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本文編號：1953610