基于结构与流场分析的超声波流量计结构设计

发布时间：2018-06-10 17:19

本文选题：超声波气体流量计 + 测量精度　；参考：《浙江大学》2015年硕士论文

【摘要】：超声波气体流量计因其高精度、低压损、宽量程和易于维护等优点,广泛应用于燃气输送管网、城市燃气门站和燃气储配站等场合。目前,国内的超声波气体流量计市场基本由外国品牌垄断,自主研发超声波气体流量计具有重要的意义。超声波气体流量计的研制和应用难点包括信号处理、传感器研发、流场补偿和安全性设计等方面。本文的研究内容主要集中于超声波流量计的外壳结构(基表结构和二次仪表结构)对测量性能和安全性能的影响,并以实验对相关内容进行了测试。论文的主要研究内容如下：1、超声波气体流量计管段设计中,超声波换能器安装效应对测量精度的影响。由于超声波气体流量计受被测量流场的状态的影响较大,而超声波换能器的安装在流场中会造成凸起或者凹陷结构,从而对被测量流场产生不可忽视的影响。本文研究了凸起安装、半凸安装和凹陷安装三种不同的换能器安装方式对测量性能的影响,并确定了最优的超声波换能器安装方式。2、超声波气体流量计管段设计中,温度传感器的安装位置研究。通过仿真计算,得出了温度传感器这一凸起结构在流场中的影响范围,确定了超声波气体流量计的插入式温度传感器的安装位置。3、超声波气体流量计对管段壁面粗糙度的需求研究。管道内壁的粗糙度也是影响流场状态的因素之一,本文研究了不同粗糙度下测量结果相对理想光滑壁面时的测量误差,从而确定了超声波气体流量计对管段壁面粗糙度的要求。4、超声波气体流量计的二次仪表外壳设计。由于超声波气体流量计工作环境的特殊性(易燃易爆场合),其二次仪表必须得到额外的防护,以免其产生的热量或者电火花导致爆炸事故的发生。本文设计了超声波气体流量计二次仪表的隔爆型仪表外壳,并以仿真计算和实验的方式验证了设计的合理性。
[Abstract]:Ultrasonic gas Flowmeter is widely used in gas distribution network, city gas gate station and gas storage station because of its high precision, low pressure loss, wide measuring range and easy maintenance. At present, the domestic ultrasonic gas Flowmeter market is basically monopolized by foreign brands. It is of great significance to develop ultrasonic gas Flowmeter independently. The development and application of ultrasonic gas Flowmeter include signal processing, sensor development, flow field compensation and safety design. This paper focuses on the influence of the shell structure (base table structure and secondary meter structure) of the ultrasonic Flowmeter on the measurement performance and safety performance. The main contents of this paper are as follows: 1. The influence of the installation effect of ultrasonic transducer on the measurement accuracy in the design of ultrasonic gas Flowmeter pipe section. Because the ultrasonic gas Flowmeter is greatly affected by the state of the measured flow field, the installation of the ultrasonic transducer in the flow field will cause bulge or hollow structure, which will have an unnegligible effect on the measured flow field. In this paper, the influence of three different transducer installation modes on the measurement performance is studied, and the optimum installation mode of ultrasonic transducer .2. the design of the pipe section of ultrasonic gas Flowmeter is determined. Research on the installation position of temperature sensors. Through the simulation calculation, the influence range of the raised structure of the temperature sensor in the flow field is obtained. The installation position of inserted temperature sensor of ultrasonic gas Flowmeter is determined. The requirement of ultrasonic gas Flowmeter for wall roughness of pipe section is studied. The roughness of the inner wall of the pipe is also one of the factors affecting the flow field. The measurement error of the measured results under different roughness is studied in this paper. The requirements of ultrasonic gas Flowmeter for wall roughness of pipe section. 4. The design of secondary instrument shell of ultrasonic gas Flowmeter. Because of the particularity of the working environment of ultrasonic gas Flowmeter (flammable and explosive occasions), the secondary instrument must be protected to avoid the explosion accident caused by the heat or electric spark. In this paper, the flameproof shell of the secondary instrument for ultrasonic gas Flowmeter is designed, and the rationality of the design is verified by simulation and experiment.
【学位授予单位】：浙江大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TH814.92

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