【作者】 于碧涌；

【导师】 段常贵；

【作者基本信息】 哈尔滨工业大学 ， 供热、供燃气、通风及空调工程， 2007， 博士

【摘要】 21世纪是世界天然气工业高速发展的时期,也是我国天然气工业兴起并走向成熟的时期,我国燃气事业正在迅猛地发展,工程量的增加将直接导致对燃气设备需求量的加大。燃气调压器是燃气工程中一种非常重要的设备,其功能是在燃气需用工况发生变化时自动地控制出口压力,使之在规定的范围内变化,保证燃气压力正常,并通常具有一定的安全保护功能。目前,我国燃气调压器设备的国产率并不高,燃气调压器面临需求量大、国产率低、研究少的局面,这与我国正在飞速发展的燃气事业的需求是极不相称的。加强燃气调压器的机理分析和设计研究工作,对于开发出优质的国产设备,发展我国的燃气事业,节省投资,有着非常重要的意义。本文以自主设计的RTZ-21/50FS(Q)型燃气调压器试验系统为研究对象,建立三维几何模型,进行网格划分,在一系列进口压力和阀口开度下进行了数值模拟,通过对阀杆的受力分析模拟出RTZ-21/50FS(Q)型燃气调压器的流量特性曲线,寻求了一条燃气调压器数值模拟的途径。燃气调压器数值模拟的目的是在设备制造之前即获得其调压性能参数,即模拟出调压特性,从中寻找不足,从而有针对性地进行改进设计,或者验证改进设计的效果,避免仅凭经验反复多次制造样机造成的研发时间和经费上的浪费。燃气调压器数值模拟以样机试验系统作为研究对象,从样机试验系统中确定出一部分作为数值模拟的范围,经过适当的简化后,对其进行几何建模,建立起燃气调压器数值模拟的三维几何模型。将燃气调压器的三维几何模型引入CFD专业前处理软件,构建一系列主阀口开度下的几何模型,组合成气体流动空间,再根据各部分的特点,选择合适的网格划分算法进行网格划分,定义边界条件,最后输出网格。将网格引入CFD专业软件FLUENT,设定合适的解的格式、流动模型、流体性质和边界条件,对一系列主阀口开度、多种入口压力、不同流量的燃气流动分别进行模拟计算,得到燃气调压器各种工况下的运行参数。建立燃气调压器的关键部件的数学模型,通过分析阀杆的受力,调节运行工况,求出多组阀杆受力平衡的工作点,组成燃气调压器的流量特性曲线。通过对模拟出的流量特性曲线分析发现燃气调压器的调压特性存在的不足。从而有针对性地进行改进设计和重新设定,并分别进行数值模拟计算,通过比较流量特性曲线图的变化预测改进设计和重新设定的效果。依照有关国家标准,设计建立了RTZ-21/50FS(Q)型燃气调压器试验系统,对试验样机进行了调压特性试验,并将数值模拟出的流量特性曲线和实测的流量特性曲线进行了对比,分析了产生模拟误差的原因和减小模拟误差的途径。更多还原

【Abstract】 The 21 century is the high speed develop period of natural gas industry in the world, at the same time it is the rise and tend towards maturity period of natural gas industry of China. Gas projects are developing impetuously in China now, the requirement for gas equipment will increase as a result of engineering expand. Gas regulator is one of the important equipment in the gas distribution system which can control the outlet pressure in a set range automatically to hold the gas pressure normal when the system state of supply and demand is changed. Moreover, it usually has the function of protection. Presently, gas regulator of high quality is seldom made in China, it is heavy required but low independence and few study. It is unsuitable to meet the need of the rapid developing of gas projects in our country. Enhancing the work of mechanism analyze and design investigation of gas regulator is very important to produce the high quality equipment and developing gas project of our country and investment saving. The study object in this paper is the regulate characteristic testing system of the RTZ-21/50FS(Q) gas regulator which independence design. The technique of gas regulator numerical simulation is work out with three dimensions geometry modeling, meshing, numerical simulating of a series of inlet pressure and orifice open extent, gained the pressure regulate characteristic simulation curve of the RTZ-21/50FS(Q) gas regulator by mechanics analyze on stem.The intention of gas regulator numerical simulation is obtain it’s regulate characteristic data, namely regulate characteristic, before the equipment is manufactured. Base on it, the disadvantage of design can be found out, accordingly, improve design can be processed pertinently or forecast the result of improve design to avoid the waste of develop time and outlay which come from manufactured sample equipment time after time with experience only. The study object of gas regulator numerical simulation is the regulate characteristic testing system of the sample equipment, a part of it is decided as the numerical simulation area. After appropriately simplify, it is geometry modeling, the three dimensions geometry model of gas regulator numerical simulation is created.The three dimensions geometry model of gas regulator is imported in the CFD professional preliminary treatment software, geometry model of a series of orifice open extent are created and then gas flow space are constructed. According as the characteristic of every part, it is meshing after chosen suitable meshing arithmetic and boundary setting. Last, the mesh is export.The mesh is imported in FLUENT, the CFD professional software, it is setting that the suitable solution format, flow model, fluid property and boundary condition. The gas flow is numerical simulated at a series of orifice open extent,several inlet pressure and different flux, then gained the gas regulator working parameter of various status. The key part’s mathematics model of the gas regulator is established, by mechanics analyze on stem and adjust status many group work point that the stem stand in mechanical balance. The flux characteristic curve of the gas regulator is constituted.The disadvantage of the gas regulator’s pressure regulate characteristic is detected by analyze the flux characteristic simulation curve. Accordingly, improve design and reset is processed pertinently before simulating in turn. Through compare the pressure regulate characteristic simulation curves, the result of improve design and reset is forecast. According to the international standard involved, the characteristic testing system of the RTZ-21/50FS(Q) gas regulator is established. The sample equipment is tested on pressure regulate characteristic. The curve of flux characteristic which simulated and tested is compared. It is analyzed the numerical simulation error causation and the way to reduce it.更多还原