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引射器关键结构参数优化设计及验证
Optimum design and verification of ejector′s main structural parameters
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刘培启,王海涛,武锦涛,朱立志,胡大鹏
- , 2017, DOI: 10.7511/dllgxb201701005
Abstract: 引射器的性能受几何尺寸影响,相关设计方法给出的结果差异较大,存在设计点偏离严重的问题.针对小膨胀比煤层气气井引射需要,利用基于气体动力学理论的索科洛夫经验公式对引射器进行初步设计,并通过CFD方法对其关键结构尺寸进行数值优化,得到关键结构参数如喷嘴间距、混合室直径、混合室长度及扩压室长度等对引射器性能的影响规律.对比分析理论设计和模拟优化得到的引射器几何尺寸,发现CFD方法优化后的引射器等熵效率较理论设计高出13%左右,并通过实验验证引射器在偏离设计工况时,等熵效率急剧降低,表明数值模拟设计的引射器效率最高,在工程上为偏离设计工况的引射器设计提供了参考.
The ejector′s performance could be affected easily by the geometric dimension, and different design methods would lead to quite different results, the design point would be seriously deviated. In order to meet the needs of ejection in coal-bed methane with small expansion ratio, the gas ejector is designed according to the Sokolov empirical formulas which are based on aerodynamics theory, and the key structural dimensions are simulated and optimized by CFD method. The influence rule of the ejector′s key structural parameters, such as the nozzle distance, the mixing chamber diameter, the mixing chamber length and the diffuser chamber length on the ejector performance is obtained. By comparing the results of theoretical design and numerical simulation, the isentropic efficiency of the ejector which was optimized by CFD method is about 13% higher than that of using theoretical design. Then, it is verified through experiments that the isentropic efficiency of the ejector will sharply reduce when the operating condition deviates from the design condition. It is proved that the ejector designed by numerical simulation has the higher efficiency, which provides reference to the design of ejector deviating from the design point in engineering.
引射技术及其在天然气处理中的应用
Ejector Technology and Its Application in Dispose Processing of Natural Gas
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张明益, 李静, 邹应勇, 刘武, 刘培启, 胡大鹏
Hans Journal of Chemical Engineering and Technology (HJCET) , 2013, DOI: 10.12677/HJCET.2013.31007
Abstract: 采用理论分析和数值计算相结合,进行了引射装置设计,并以牙哈气田为例,探讨了引射装置用于天然气田轻烃回收工艺时存在的优势,得出主要结果和结论如下:1) 本文建立的引射装置数值计算模型能够得到装置内部流场信息,可用于装置结构的优化;2) 喷嘴可调引射器结构,可提高装置工况适用性,可实现不同流量的调节;3) 引射技术能够利用高压天然气自身压力能引射低压流体,大幅度减小凝析气田轻烃回收装置的能耗,为天然气集输处理提供一个新途径。
The method of theoretical analysis combining with numerical calculation in this paper has been adopted to design ejector device, and the YaHa oil-gas field has been cited as an example to discuss the advantages of ejector device used in the process of light hydrocarbon recovery from condensate field. The main results and conclusions are as follows: 1) The established numerical model of ejector machine can get the information of internal flow inside the device, so it could be used in the optimization of device structure; 2) The adjustable nozzle of ejector structure can improve the appli- cability of operational condition and realize regulation for different flow rate; 3) The ejector technology can utilize the high pressure gas with high pressure energy itself to inject the low pressure fluid and greatly reduce the energy consump- tion of light hydrocarbon recovery, providing a new way for natural gas gathering and transferring process.
制冷剂两相流音速对引射器喷嘴结构的影响
Effect of sonic velocity of two-phase refrigerant fluid on structure of ejector nozzle
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李应林,周飞,张小松,杜垲,张忠斌,陈传宝,谭来仔
- , 2015, DOI: 10.3969/j.issn.1001-0505.2015.01.017
Abstract: 将液-液引射器内部的喷嘴作为研究对象,建立了喷嘴内气液两相流的非等熵膨胀模型和均相流音速模型.研究了制冷剂R134a和R22在不同喷嘴进出口压降条件下,喷嘴出口气液两相流音速的变化规律.模拟结果表明:随着喷嘴出口饱和温度的降低,喷嘴出口音速缓慢降低,而实际速度快速增大,喷嘴出口处R22的当地音速约为R134a当地音速的1.5倍;当喷嘴入口饱和温度为40 ℃时,R134a在喷嘴内实际膨胀过程的临界温度为14.5 ℃;对于高压液体作为工作流体的引射器,其喷嘴宜采用缩放型;当喷嘴入口饱和温度分别为40和50 ℃时,R22在喷嘴内实际膨胀过程的临界温度分别为-3.5和3.0 ℃,宜采用渐缩型喷嘴.
The nozzle of a liquid-liquid ejector is selected as the research object, and a non-isentropic expanding model and a homogeneous sonic model of gas-liquid two-phase fluid in the nozzle are established. Then the change trend of sonic velocities of R134a and R22 under different inlet-outlet pressure drop of nozzle are investigated. Simulation results show that, with the decrease of saturation temperature of the nozzle outlet, the local sonic velocity of nozzle outlet decreases slowly. But the actual speed of nozzle outlet increases quickly, the sonic velocity of R22 in the nozzle outlet is about 1.5 times that of R134a. While the temperature of nozzle inlet maintains 40 ℃, the critical temperature of R134a in the actual expanding process is about 14.5 ℃, and a convergent-divergent nozzle should be adopted for the ejector. When the inlet saturated temperature of nozzle are 40 and 50 ℃, the critical temperatures of R22 in the actual expansion process are -3.5 and 3.0 ℃, respectively, and a tapered nozzle should be used for the ejector
工况对两相流引射器制冷循环系统性能的影响
Effects of operating conditions on performance of two-phase ejector refrigeration cycle system
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郭宪民,丁明青,张佩兰
- , 2018, DOI: 10.13738/j.issn.1671-8097.117044
Abstract: 引射器结构简单、无运动部件,在制冷系统中代替膨胀阀可提高系统的COP。本文以R134a为工质,实验研究了不同工况条件下两相流引射器制冷循环系统性能,分析了蒸发温度、冷凝温度对引射比、压力提升比、制冷量和系统COP的影响。研究发现,当冷凝温度为40℃时,随着蒸发温度的提高,引射比和压力提升比均下降,制冷量和系统COP均提高;当蒸发温度为-10℃时,随着冷凝温度的增加,引射比和压力提升比均增大,制冷量和系统COP均下降。
The ejector has the advantages of simple structure and no moving parts. By using ejector instead of expansion valve in the refrigeration system, the COP of the system can be improved. In this paper, the experimental studies on the performances of the two-phase ejector refrigeration systems with the refrigerant R134a as working fluid under different conditions were carried out. The influences of the evaporating and condensing temperatures on the entrainment ratio, pressure lifting ratio, refrigeration capacity and system COP were analyzed. The experimental results indicate that the entrainment ratio and pressure lifting ratio decrease with the increase of evaporating temperature at the condensing temperature of 40℃. The entrainment ratio and pressure lifting ratio increase, while the refrigeration capacity and system COP decrease with the increase of condensing temperature at the evaporating temperature of -10℃.
RBCC用变工况气氧/煤油引射火箭发动机设计和试验研究
Design and Experimental Investigation on Gas Oxygen/Kerosene Ejector Rocket for RBCC Application
 [PDF]

魏祥庚,秦飞,石磊,张保庆,何国强
- , 2018,
Abstract: 引射火箭是火箭冲压组合发动机的核心部件之一,须具有变工况工作能力。针对RBCC发动机用引射火箭的技术要求,基于挤压式推进剂供应系统,设计了变工况工作气氧/煤油引射火箭系统,完成了4种工作状态下的点火试验验证。试验研究结果表明,设计的变工况工作引射火箭发动机稳定可靠工作,工作参数满足设计要求,可实现快速调节。为开展火箭冲压组合发动机试验及大调节比引射火箭技术研究奠定了基础。
The ejector rocket is one of the core components of the rocket based combined cycle propulsion system, and must be capable of variable working conditions. In order to meet technical requirements for RBCC application, the variable duty operating ejector rocket using the gas Oxygen/Kerosene was designed based on the gas pressurized propellant feed systems. Hot firing tests of four different working conditions had been completed. Experimental results show that the designed ejector rocket engine was stable and reliable, and the working parameters met the design requirements, and the working conditions were adjusted quickly. It lays a foundation for the study of the RBCC engine test and the engine technology of large adjustment ratio
一种射束与像素的快速遍历和求交算法  [PDF]
张顺利,张定华,赵歆波,黄魁东
中国图象图形学报 , 2009, DOI: 10.11834/jig.20091006
Abstract: 针对ART(algebraicreconstructiontechnique)算法重建速度慢的问题,提出了一种射束与像素的快速遍历和求交算法。该算法通过一个距离参数来确定射束穿过的像素索引并计算出射束覆盖像素的面积,距离参数采用增量计算,因而运算效率很高。利用该算法在图像重建过程中实时计算权因子,不但节省了大量的内存空间,而且大大提高了图像重建的速度。实验结果表明,提出的算法非常有效,与传统方法相比取得了17倍以上的重建加速比。
Experimental investigation into flow in an ejector with four synthetic jets  [cached]
Dvo?ák Václav,Dan?ová Petra,?varc Petr
EPJ Web of Conferences , 2012, DOI: 10.1051/epjconf/20122502003
Abstract: The article deals with experimental investigation into flow in an ejector with four synthetic jets. The aim of the synthetic jets is to excite the mixing layer in the ejector and intensify the mixing process. The cavities of the synthetic jet actuators are hidden in the mixing chamber wall and the synthetic jets are perpendicular to the ejector axis. CTA and pneumatic measuring method were used to investigate the influences of synthetic jets on flow inside the ejector.
A Review On Historical And Present Developments In Ejector Systems  [PDF]
Mohammed Raffe Rahamathullah
International Journal of Engineering Research and Applications , 2013,
Abstract: Ejectors are simple pieces of equipment. Nevertheless, many of their possible services are overlooked. They often are used to pump gases and vapours from a system to create a vacuum. However, they can be used for a great number of other pumping situations. This paperprovides reviewon the development in ejectors, applications of ejector systems and system performance enhancement. Several topics are categorized provides useful guidelines regarding background and operating principles of ejector including mathematical modelling, numerical simulation of ejector system, geometric optimizations. Research works carried out recently are still limited to computer modelling, forthe real industrial applications more experimental and large-scale work are needed in order to provide better understanding.
GAS EJECTOR AS A PRESSURE STABILIZER AT THE INLET TO COMPRESSOR POWER INSTALLATION Газовый эжектор как стабилизатор давления на входе в компрессорную энергетическую установку Газовий ежектор як стаб л затор тиску на вход в компресорну енергетичну установку  [cached]
M.S. Kulyk,К.I. Kapitanchuk,P.I. Grekov,S.P. Onischenko
Proceedings of National Aviation University , 2005,
Abstract: Optimum supersonic gas ejector design procedure for application as pressure stabilizer at the inlet to compressor power installation is developed. Разработана методика расчета оптимального сверхзвукового газового эжектора для применения в качестве стабилизатора давления на входе в компрессорную энергетическую установку. Розроблено методику розрахунку оптимального надзвукового газового ежектора для використання як стаб л затора тиску на вход в компресорну енергетичну установку.
Simulation of Supersonic Flow in an Ejector Diffuser Using the JPVM  [PDF]
Carlos Couder-Casta eda
Journal of Applied Mathematics , 2009, DOI: 10.1155/2009/497013
Abstract: The ejectors are used commonly to extract gases in the petroleum industry where it is not possible to use an electric bomb due the explosion risk because the gases are flammable. The steam ejector is important in creating and holding a vacuum system. The goal of this job is to develop an object oriented parallel numerical code to investigate the unsteady behavior of the supersonic flow in the ejector diffuser to have an efficient computational tool that allows modeling different diffuser designs. The first step is the construction of a proper transformation of the solution space to generate a computational regular space to apply an explicit scheme. The second step, consists in developing the numerical code with an-object-oriented parallel methodology. Finally, the results obtained about the flux are satisfactory compared with the physical sensors, and the parallel paradigm used not only reduces the computational time but also shows a better maintainability, reusability, and extensibility accuracy of the code.
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