V形调节球阀阀芯结构与等百分比流量特性分析

发布时间：2018-01-26 17:28

本文关键词： V形球阀阀芯结构流量系数等百分比流量特性　出处：《兰州理工大学》2012年硕士论文　论文类型：学位论文

【摘要】：自20世纪70年代国外发明了V形调节球阀以来，由于其具有流体阻力小，流通能力大、开关迅速、密封性能好、寿命长、可调比高等优点，在工业生产中的含有纤维介质的流体系统中得到了非常广泛的应用。V形球阀从80年代开始引入我国，到目前为止在国内只有少数厂家能够制造V形球阀，且都是以经验参数设计为主，仍然有一些关键技术没有掌握，调节性能依然较低，产品难以达到理想等百分比流量特性。本文研究了V形球阀的基本结构，给出了主要的结构参数，如阀芯球冠底圆的弦长，球冠的半径，旋转中心至球冠底圆的高度，V形开口的大小及位置等，推导出了不同开度下流通面积与流量系数之间的关系，提出了参数优化要求。 V形球阀的流量特性分析主要是讨论流通面积的分析，不同的流通面积便有不同的流阻，由此得到的流量系数也不一样，想要使流量特性达到等百分比流量特性，必须改变不同开度下的流通面积，，使设计的流量系数与等百分比流量特性的流量系数接近，从而改善其流量特性。根据V形球阀的结构机理和运动关系建立了阀芯转动的三维数学模型，对阀芯的各个参数进行调整，使不同开度下的流量系数符合等百分比流量特性的要求。本文还对该设计计算方法进行了验证，根据原阀芯结构计算得到的流量系数与试验测试得到的流量系数非常接近，证明了利用此方法改变阀芯结构参数以优化流量特性的正确性与可行性。在此计算的基础上，又开发了相应的优化软件，利用此优化软件可方便快捷的改变阀芯的结构参数，直至找到与等百分比流量特性相符的阀芯结构。通过上述的研究，有效的提高了V形球阀的流量特性，使V形球阀的设计流量特性与等百分比流量特性趋于一致，减小流量系数误差。本文推导的等百分比流量特性的V形球阀在不同开度下的流通面积计算公式、流量系数计算方法及相应的优化软件，为工程设计提供了一种快捷高效的计算方法,简化了设计的计算过程，优化了阀芯结构，提高了V形球阀的调节特性。
[Abstract]:Since the invention of V-shaped ball valve in 1970s, it has the advantages of low fluid resistance, large flow capacity, fast switching, good sealing performance, long life, high adjustable ratio and so on. It has been widely used in the fluid system with fiber medium in industrial production. Since 80s, the V-shaped ball valve has been introduced into China. Up to now, only a few manufacturers have been able to manufacture V-shaped ball valve in our country. All of them are mainly based on the experience parameter design, there are still some key technologies not mastered, the adjustment performance is still low, the product is difficult to achieve the ideal equal percentage flow characteristics. In this paper, the basic structure of V-shaped ball valve is studied, and the main structural parameters are given, such as the chord length of the bottom circle of the core spherical crown, the radius of the spherical crown, the height of the V-shaped opening from the center of rotation to the circle of the bottom of the spherical crown, and so on. The relationship between flow area and flow coefficient under different opening is deduced, and the parameter optimization requirements are put forward. The flow characteristic analysis of V-shaped ball valve is mainly to discuss the analysis of circulation area, different circulation area has different flow resistance, and the flow coefficient is also different. In order to make the flow characteristic reach the equal percentage flow characteristic, the flow area under different opening must be changed, so that the designed flow coefficient is close to the flow coefficient of equal percentage flow characteristic. According to the structure mechanism and motion relation of V-shaped ball valve, the three-dimensional mathematical model of valve core rotation is established, and the parameters of valve core are adjusted. The flow coefficient under different opening meets the requirement of equal percentage flow characteristic. The flow coefficient calculated according to the original valve core structure is very close to the flow coefficient obtained from the test. It is proved that it is correct and feasible to use this method to change the structure parameters of the valve core to optimize the flow characteristics. On the basis of this calculation, the corresponding optimization software is developed. By using this optimization software, the structure parameters of the spool can be changed conveniently and quickly until the spool structure which is consistent with the equal percentage flow characteristics can be found. Through the above research, the flow characteristics of V-shaped ball valves are improved effectively, and the design flow characteristics of V-shaped ball valves tend to be consistent with the equal percentage flow characteristics. To reduce the error of flow coefficient, the formula for calculating flow area of V-shaped ball valve with equal percentage flow characteristics under different opening degrees, the calculation method of flow coefficient and the corresponding optimization software are derived in this paper. It provides a fast and efficient calculation method for engineering design, simplifies the calculation process of the design, optimizes the valve core structure, and improves the adjusting characteristics of the V-shaped ball valve.
【学位授予单位】：兰州理工大学
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：TH134

【参考文献】