高压共轨轨腔内部流动数值分析
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摘要
高压共轨是控制柴油机排放的一项新技术,国内还处于发展阶段,因此具有研究的实际意义。共轨式内燃机的流体动力特性是共轨式内燃机的重要特性,对内燃机的动力性和燃油经济性有重要影响,这种影响通过速度场、温度场与压力场表现出来。数值模拟是研究流体动力性的直观而有效的研究方法.本文利用流体动力学仿真软件FLUENT研究探讨高压共轨轨腔结构与内部流动特性的关系。
本文详细分析了高压共轨轨腔模型的简化过程、影响因素以及目前该领域的研究现状。并介绍了FLUENT/GAMBIT软件的操作方法和理论基础,为后面的建模和数值分析奠定了基础。
本文利用GAMBIT2.3软件建立了高压共轨轨腔各种方案的几何模型并划分六面体网格。在用FLUENT数值分析中,首先计算分析了三种极限截面形状轨腔的流动特性,比较出较优的轨腔截面形状。其次,对轨腔截面形状进一步计算分析,比较出最佳截面形状。最后,分别计算分析进气口压力、容积以及小倒角方案的流场特性,并分析其对轨腔内部流场特性的影响。
结果表明:高压轨腔最大壁面夹角在80°～90°范围内,有较好的流场特性,并且在本模型中最大壁面夹角为的84°轨腔模型时,流场特性最佳。比较分析轨腔的各种模型方案,认为进口压力只能改变各位置的速度大小而不影响流场特性;较大的轨腔容积的保压性能提高并且压力损失小;小倒角是有利的,但最大倒角必须使最大壁面夹角在80°～90°范围内。
High Pressure Common Rail is a new technology for controlling diesel engine emission and still is in development stage in China, so it has the practical significance of studying. Fluid dynamic characteristics of the Common Rail is an important characteristic of the internal combustion engine and has an important effect to the internal combustion engine power performance and fuel economy, which is shown by velocity, temperature and pressure field. Numerical simulation is an intuitive and effective method of researching fluid dynamics. This article uses CFD simulation software FLUENT to study relationship between the cavity of the High-Pressure common rail and the characteristics of flowing.
In this paper, the simplify process of the cavity model, the impact of factors and the current researching status of the High-Pressure common-rail is analyzed. And then the operating methods and the basic theories of FLUENT/GAMBIT software is introduced, which is the foundation of modeling and numerical analysis.
In this article, GAMBIT2.3 is used to establish various schemes of the cavity High-Pressure common rail and mesh the hexahedral gridding. Firstly, the characteristics of flowing about the three limit cross-section shapes of the cavity is analyzed in numerical analysis of FLUENT and compared to optimum cross-section shape of the common rail cavity. Secondly, the cross-section shape of the cavity is also analyzed and compared to the best cross-section shape of the cavity. Lastly, the fluid characteristics of the schemes of the inlet pressure, volume and small chamfering are respectively analyzed as well as its influence about the fluid characteristics.
The results show that, when the largest wall angle of the High-Pressure is within 80 to 90 degree, there is a better fluid characteristic. When the largest wall angle of the model is 84 degree, it has the fluid characteristic of the best. By comparative and analysis of the various scheme, it concludes that the inlet pressure scheme can only change the value without affecting the flow characteristics; Larger volume scheme of common rail can improve pressure-retaining capacity and has a small pressure loss; The small chamfering is beneficial, but the biggest chamfer value must ensure the largest wall angle is within 80 to 90 degree.
本文详细分析了高压共轨轨腔模型的简化过程、影响因素以及目前该领域的研究现状。并介绍了FLUENT/GAMBIT软件的操作方法和理论基础,为后面的建模和数值分析奠定了基础。
本文利用GAMBIT2.3软件建立了高压共轨轨腔各种方案的几何模型并划分六面体网格。在用FLUENT数值分析中,首先计算分析了三种极限截面形状轨腔的流动特性,比较出较优的轨腔截面形状。其次,对轨腔截面形状进一步计算分析,比较出最佳截面形状。最后,分别计算分析进气口压力、容积以及小倒角方案的流场特性,并分析其对轨腔内部流场特性的影响。
结果表明:高压轨腔最大壁面夹角在80°～90°范围内,有较好的流场特性,并且在本模型中最大壁面夹角为的84°轨腔模型时,流场特性最佳。比较分析轨腔的各种模型方案,认为进口压力只能改变各位置的速度大小而不影响流场特性;较大的轨腔容积的保压性能提高并且压力损失小;小倒角是有利的,但最大倒角必须使最大壁面夹角在80°～90°范围内。
High Pressure Common Rail is a new technology for controlling diesel engine emission and still is in development stage in China, so it has the practical significance of studying. Fluid dynamic characteristics of the Common Rail is an important characteristic of the internal combustion engine and has an important effect to the internal combustion engine power performance and fuel economy, which is shown by velocity, temperature and pressure field. Numerical simulation is an intuitive and effective method of researching fluid dynamics. This article uses CFD simulation software FLUENT to study relationship between the cavity of the High-Pressure common rail and the characteristics of flowing.
In this paper, the simplify process of the cavity model, the impact of factors and the current researching status of the High-Pressure common-rail is analyzed. And then the operating methods and the basic theories of FLUENT/GAMBIT software is introduced, which is the foundation of modeling and numerical analysis.
In this article, GAMBIT2.3 is used to establish various schemes of the cavity High-Pressure common rail and mesh the hexahedral gridding. Firstly, the characteristics of flowing about the three limit cross-section shapes of the cavity is analyzed in numerical analysis of FLUENT and compared to optimum cross-section shape of the common rail cavity. Secondly, the cross-section shape of the cavity is also analyzed and compared to the best cross-section shape of the cavity. Lastly, the fluid characteristics of the schemes of the inlet pressure, volume and small chamfering are respectively analyzed as well as its influence about the fluid characteristics.
The results show that, when the largest wall angle of the High-Pressure is within 80 to 90 degree, there is a better fluid characteristic. When the largest wall angle of the model is 84 degree, it has the fluid characteristic of the best. By comparative and analysis of the various scheme, it concludes that the inlet pressure scheme can only change the value without affecting the flow characteristics; Larger volume scheme of common rail can improve pressure-retaining capacity and has a small pressure loss; The small chamfering is beneficial, but the biggest chamfer value must ensure the largest wall angle is within 80 to 90 degree.
引文
[1]李长河等.柴油机共轨喷射系统的发展及关键技术.内蒙古民族大学学报(自然科学版),2003(2):138-141.
[2]刘斌彬,李国岫,郑亚银.柴油机高压共轨燃油喷射系统现状与发展趋势.内燃机.2006(2):1-3.
[3]王均效,陆家祥,等.柴油机高压共轨喷油系统的发展动态.柴油机,2001(5).
[4]甄华翔.转动车轮对轿车外流场影响的数值模拟:(硕士学位论文).大连:大连理工大学,2007.
[5]黄向东.汽车空气动力学与车身造型.人民交通出版社,2000.
[6]傅立敏.汽车空气动力学.机械工业出版社,1998.
[7]王晓峰,靳春士.柴油机共轨技术简介.汽车运用,2002(6):21.
[8]刘旭刚等.柴油发动机高压共轨技术的产生与发展.汽车运用,2007(11):30-31.
[9]李根生.空化与空蚀机理及其影响因素.石油大学学报(自然科学版),1997(1):97-102.
[10]王立军.高压共轨喷油系统在柴油机上的应用.农业机械化与电气化,2004(6):23.
[11]张剑平等.高压共轨燃油系统特性试验研究.内燃机工程,2005(2):13-16.
[12]颜松.柴油机高压共轨系统压力动态特性模拟:(硕士学位论文).浙江:浙江大学,2005.
[13]Sulzer RT-Flex说明书.
[14]http://www.wartsila.nsd.com.
[15]The Sulzer RT-Flex engine,Marketing RT-Flex.
[16]王宏明,胡明.Sulzer RT-flex柴油机WECS-9500控制系统.天津航海,2007(1):28-31.
[17]秦朝举等.Bosch公司高压共轨喷油系统的研究现状及发展前景.拖拉机与农用运输车,2006(2):3-5.
[18]More Torque,Less Emissions,Less Noise from Diesel Engines[J].SAE Paper:2000-01-0942
[19]Cichocki R.Technologies for future HSDI passenger car diesel engine.International symposium power train technologies for a 3 liter car.
[20]Kato T,T sujimura KM,Minami T,eta1 Spray Characteristics and Combustion Improvement of D.I.Diesel Engine with High Fuel Injection[C].SAE Paper 890265,1989.
[21]Digesu P,Ficarella A,Laforgia D.Diesel Electro-Injector:A Numerical Simulation Code[C].SAE Paper 940193,1994.
[22]K.Komlyama,etc,Electronically Controlled High Pressure Injection System for Heavy Duty Diesel Engine,SAE 810997.
[23]S.F.Glassey,A.R.Stockner,M.A.Flinn,HEUI-A New Dirction for Diesel Engine Fuel Systems,SAE 930270
[24]Jonathan Walker.高压共轨系统的开发.国外内燃机车,2004(3):9-11.
[25]EI Tahry S.Application of a Reynolds Stress Model to Engine Like Flow Calculations.Transactions of ASME.107,1985.
[26]Bas yen den Heuvel.In-Cylinder Flow Analysis for Production Type Internal Combustion Endines.Printed in the Netherlands,1998.
[27]Launder B E and Spalding B E.The Numerical Computation of Turbulence Flow.Comp.Meth. Appl.Mech.Eng.1974,3:269.
[28]www.efluid.com.cn
[29]王瑞金,张凯,王刚.Fluent技术基础与应用实例.清华大学出版社,2007.
[30]韩占忠,王敬,兰小平.FLUENT-流体工程仿真计算实例与应用.北京:北京理工大学出版社,2004.
[31]王福军.计算流体动力学分析-CFD软件原理与应用.北京:清华大学出版社,2007.
[32]潘剑锋等.柴油机中压共轨式喷油系统的模拟计算与分析.汽车工程,2003(4):338-342.
[33]党杰.柴油机共轨燃油喷射系统简介.中国修船,2004(1):22-23.
[34]GAMBIT USER'S GUIDE,FLUENT.Inc
[35]ANSYS FLUENT6.3 help.
[36]周龙保等.内燃机学(第2版).机械工业出版社,2003.
[37]王好战等.高压共轨电控柴油机稳态油压模拟计算及分析.内燃机工程,2002(6):9-11.
[38]陈廷明,李霞明.蓄压式共轨喷油器结构参数的数值模拟研究.农机化研究,2005(4):251-253.
[39]何志霞等.柴油机高压共轨喷油系统内的瞬变流动研究.农业机械学报,2004(1):48-51.
[40]李强,覃维献.柴油机高压油道压力波动特性的模拟计算.桂林航天工业高等专科学校学报,2006(4):31-32.
[41]梁超.电控柴油机共轨管内压力波动性研究:(硕士学位论文).哈尔滨:东北林业大学,2006.
[42]吴建.柴油机共轨式电控喷射系统喷射过程的模拟计算和研究:(博士学位论文).湖南:湖南大学,2002.
[43]张林夫,夏维洪.空化与空蚀,河海大学出版社,1989.
[2]刘斌彬,李国岫,郑亚银.柴油机高压共轨燃油喷射系统现状与发展趋势.内燃机.2006(2):1-3.
[3]王均效,陆家祥,等.柴油机高压共轨喷油系统的发展动态.柴油机,2001(5).
[4]甄华翔.转动车轮对轿车外流场影响的数值模拟:(硕士学位论文).大连:大连理工大学,2007.
[5]黄向东.汽车空气动力学与车身造型.人民交通出版社,2000.
[6]傅立敏.汽车空气动力学.机械工业出版社,1998.
[7]王晓峰,靳春士.柴油机共轨技术简介.汽车运用,2002(6):21.
[8]刘旭刚等.柴油发动机高压共轨技术的产生与发展.汽车运用,2007(11):30-31.
[9]李根生.空化与空蚀机理及其影响因素.石油大学学报(自然科学版),1997(1):97-102.
[10]王立军.高压共轨喷油系统在柴油机上的应用.农业机械化与电气化,2004(6):23.
[11]张剑平等.高压共轨燃油系统特性试验研究.内燃机工程,2005(2):13-16.
[12]颜松.柴油机高压共轨系统压力动态特性模拟:(硕士学位论文).浙江:浙江大学,2005.
[13]Sulzer RT-Flex说明书.
[14]http://www.wartsila.nsd.com.
[15]The Sulzer RT-Flex engine,Marketing RT-Flex.
[16]王宏明,胡明.Sulzer RT-flex柴油机WECS-9500控制系统.天津航海,2007(1):28-31.
[17]秦朝举等.Bosch公司高压共轨喷油系统的研究现状及发展前景.拖拉机与农用运输车,2006(2):3-5.
[18]More Torque,Less Emissions,Less Noise from Diesel Engines[J].SAE Paper:2000-01-0942
[19]Cichocki R.Technologies for future HSDI passenger car diesel engine.International symposium power train technologies for a 3 liter car.
[20]Kato T,T sujimura KM,Minami T,eta1 Spray Characteristics and Combustion Improvement of D.I.Diesel Engine with High Fuel Injection[C].SAE Paper 890265,1989.
[21]Digesu P,Ficarella A,Laforgia D.Diesel Electro-Injector:A Numerical Simulation Code[C].SAE Paper 940193,1994.
[22]K.Komlyama,etc,Electronically Controlled High Pressure Injection System for Heavy Duty Diesel Engine,SAE 810997.
[23]S.F.Glassey,A.R.Stockner,M.A.Flinn,HEUI-A New Dirction for Diesel Engine Fuel Systems,SAE 930270
[24]Jonathan Walker.高压共轨系统的开发.国外内燃机车,2004(3):9-11.
[25]EI Tahry S.Application of a Reynolds Stress Model to Engine Like Flow Calculations.Transactions of ASME.107,1985.
[26]Bas yen den Heuvel.In-Cylinder Flow Analysis for Production Type Internal Combustion Endines.Printed in the Netherlands,1998.
[27]Launder B E and Spalding B E.The Numerical Computation of Turbulence Flow.Comp.Meth. Appl.Mech.Eng.1974,3:269.
[28]www.efluid.com.cn
[29]王瑞金,张凯,王刚.Fluent技术基础与应用实例.清华大学出版社,2007.
[30]韩占忠,王敬,兰小平.FLUENT-流体工程仿真计算实例与应用.北京:北京理工大学出版社,2004.
[31]王福军.计算流体动力学分析-CFD软件原理与应用.北京:清华大学出版社,2007.
[32]潘剑锋等.柴油机中压共轨式喷油系统的模拟计算与分析.汽车工程,2003(4):338-342.
[33]党杰.柴油机共轨燃油喷射系统简介.中国修船,2004(1):22-23.
[34]GAMBIT USER'S GUIDE,FLUENT.Inc
[35]ANSYS FLUENT6.3 help.
[36]周龙保等.内燃机学(第2版).机械工业出版社,2003.
[37]王好战等.高压共轨电控柴油机稳态油压模拟计算及分析.内燃机工程,2002(6):9-11.
[38]陈廷明,李霞明.蓄压式共轨喷油器结构参数的数值模拟研究.农机化研究,2005(4):251-253.
[39]何志霞等.柴油机高压共轨喷油系统内的瞬变流动研究.农业机械学报,2004(1):48-51.
[40]李强,覃维献.柴油机高压油道压力波动特性的模拟计算.桂林航天工业高等专科学校学报,2006(4):31-32.
[41]梁超.电控柴油机共轨管内压力波动性研究:(硕士学位论文).哈尔滨:东北林业大学,2006.
[42]吴建.柴油机共轨式电控喷射系统喷射过程的模拟计算和研究:(博士学位论文).湖南:湖南大学,2002.
[43]张林夫,夏维洪.空化与空蚀,河海大学出版社,1989.