基于流—固耦合的轴流泵叶轮性能预测
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摘要
轴流泵在现代工业中发挥着非常重要的作用,叶轮作为轴流泵的工作部件,其性能优劣直接决定着轴流泵的效率。本文采用流-固耦合的方法对轴流泵的叶轮进行计算分析。根据流体力学和弹性力学建立了轴流泵的流-固耦合有限元方程。计算过程中采用k ?ε方程模型,并对流固耦合的求解问题进行了深入分析。
本文采用UG建模软件,建立轴流泵的叶轮实体模型和流体域模型,通过ADINA软件接口将模型数据导入ADINA软件。在ADINA-structure模块中对叶轮的结构进行求解设置,生成固体部分求解文件;在ADINA-fluid模块对流体域部分进行求解设置,生成流体部分求解文件,最后在ADINA-FSI模块中对以上两个文件进行双向耦合计算。对叶轮的三个运行工况进行计算,得到不同工况下叶轮内部应力和应变,流体速度和压力分布情况。通过对计算结果的分析得到以下结论:
1.叶轮最大应力、应变均发生在叶轮和轮毂连接的部位,越靠近叶片外缘应力值越小;并且随着流速的增大根部的应力和应变也不断增大;在设计时应注意叶轮根部区域。流场最大的压力梯度发生在叶轮根部区域,随着流速的增大,压力值也不断增大;叶片的前端变形也增大,造成轴流泵叶片的振动。长时间的运行之后容易在叶轮根部造成疲劳破坏,从而影响轴流泵的正常工作;因此应该注意叶轮根部的强度。
2.在叶片附近区域有小漩涡出现,以及由此形成的回流,破坏了内部正常流动状况,使轴流泵效率降低;因此在轴流泵设计时应该注意选取的翼型,尽量减少回流现象的发生,提高轴流泵的效率。
通过对轴流泵叶轮流固耦合的数值模拟,得到了叶轮内部真实流动情况和叶内部应力分布情况。同时,详细分析了不同工况下的流固耦合情况,为以后轴流泵叶轮设计提供一定的帮助和参考。
The axial flow pump plays an important role in the modern industry; the impeller is the key parts of axial flow pump, its performance deciding the axial flow pump's efficiency. This paper uses the fluid-solid coupling method compute the axial flow pump's impeller. According to the hydromechanics and the elasticity theory established axial flow pump's fluid - solid coupling finite element equation. In the computational process uses the k ?εequation model, and analysis the solution question in the process of fluid-solid coupling.
This paper uses the UG software, establishes axial flow pump's impeller model and fluid model, transfer the model data into the ADINA software. Carries on the solution establishment to impeller's structure in the ADINA-structure module and produce the solid solution document; Carries on the solution establishment to the fluid part in the ADINA-fluid module and produce fluid solution document, finally put the coupling computation in the ADINA-FSI module.
Compute the impeller's three working conditions, obtains the impeller internal stress and the strain on the different operating conditions, the fluid velocity and the pressure distribution situation. We can draw the important conclusion from the results of computation and analysis:
1. the impeller’s biggest stress and strain occurs in root; which connects the blade and the wheel hub, the stress becomes more smaller approaches the head of blade; the stress and strain increasing with the velocity increasing; so, when we design the impeller should pay attention to root areas. The most tremendous pressure gradient of fluid occurs in the impeller root areas, along with flow speed increased, the value of pressure and the front of blade's distortion also increased; cased the axial flow pump blade’s vibration. Working for a long time, it can easily produce the fatigue failure in the impeller root, and destroy the axial flow pump's normal work; therefore, we should pay more attention to the impeller’s intensity.
2. There have small eddy and backflow appears nearby the blade, destroy the internal normal flowing condition, which cases the axial flow pump’s efficiency become low; so we should pay attention to the selection the wing section in the process of design the axial flow pump, reduces the backflow phenomenon occurrence, raises the axial flow pump's efficiency.
We can obtain the impeller’s interior actual flow situation and the impeller internal stress distribution due to axial flow fluid-solid coupling numerical simulation. At the same time, analysis the fluid-solid coupling under different working conditions, it has provided certain help and the reference for the later axial flow pump impeller’s design.
本文采用UG建模软件,建立轴流泵的叶轮实体模型和流体域模型,通过ADINA软件接口将模型数据导入ADINA软件。在ADINA-structure模块中对叶轮的结构进行求解设置,生成固体部分求解文件;在ADINA-fluid模块对流体域部分进行求解设置,生成流体部分求解文件,最后在ADINA-FSI模块中对以上两个文件进行双向耦合计算。对叶轮的三个运行工况进行计算,得到不同工况下叶轮内部应力和应变,流体速度和压力分布情况。通过对计算结果的分析得到以下结论:
1.叶轮最大应力、应变均发生在叶轮和轮毂连接的部位,越靠近叶片外缘应力值越小;并且随着流速的增大根部的应力和应变也不断增大;在设计时应注意叶轮根部区域。流场最大的压力梯度发生在叶轮根部区域,随着流速的增大,压力值也不断增大;叶片的前端变形也增大,造成轴流泵叶片的振动。长时间的运行之后容易在叶轮根部造成疲劳破坏,从而影响轴流泵的正常工作;因此应该注意叶轮根部的强度。
2.在叶片附近区域有小漩涡出现,以及由此形成的回流,破坏了内部正常流动状况,使轴流泵效率降低;因此在轴流泵设计时应该注意选取的翼型,尽量减少回流现象的发生,提高轴流泵的效率。
通过对轴流泵叶轮流固耦合的数值模拟,得到了叶轮内部真实流动情况和叶内部应力分布情况。同时,详细分析了不同工况下的流固耦合情况,为以后轴流泵叶轮设计提供一定的帮助和参考。
The axial flow pump plays an important role in the modern industry; the impeller is the key parts of axial flow pump, its performance deciding the axial flow pump's efficiency. This paper uses the fluid-solid coupling method compute the axial flow pump's impeller. According to the hydromechanics and the elasticity theory established axial flow pump's fluid - solid coupling finite element equation. In the computational process uses the k ?εequation model, and analysis the solution question in the process of fluid-solid coupling.
This paper uses the UG software, establishes axial flow pump's impeller model and fluid model, transfer the model data into the ADINA software. Carries on the solution establishment to impeller's structure in the ADINA-structure module and produce the solid solution document; Carries on the solution establishment to the fluid part in the ADINA-fluid module and produce fluid solution document, finally put the coupling computation in the ADINA-FSI module.
Compute the impeller's three working conditions, obtains the impeller internal stress and the strain on the different operating conditions, the fluid velocity and the pressure distribution situation. We can draw the important conclusion from the results of computation and analysis:
1. the impeller’s biggest stress and strain occurs in root; which connects the blade and the wheel hub, the stress becomes more smaller approaches the head of blade; the stress and strain increasing with the velocity increasing; so, when we design the impeller should pay attention to root areas. The most tremendous pressure gradient of fluid occurs in the impeller root areas, along with flow speed increased, the value of pressure and the front of blade's distortion also increased; cased the axial flow pump blade’s vibration. Working for a long time, it can easily produce the fatigue failure in the impeller root, and destroy the axial flow pump's normal work; therefore, we should pay more attention to the impeller’s intensity.
2. There have small eddy and backflow appears nearby the blade, destroy the internal normal flowing condition, which cases the axial flow pump’s efficiency become low; so we should pay attention to the selection the wing section in the process of design the axial flow pump, reduces the backflow phenomenon occurrence, raises the axial flow pump's efficiency.
We can obtain the impeller’s interior actual flow situation and the impeller internal stress distribution due to axial flow fluid-solid coupling numerical simulation. At the same time, analysis the fluid-solid coupling under different working conditions, it has provided certain help and the reference for the later axial flow pump impeller’s design.
引文
[1]邢景棠,周盛,崔尔杰.流固耦合力学概述[J].力学进展,1997,727(:)l19-37.
[2] Westergard H. M. Water Pressure on dams during earthquakes[M]. Trans. Amer Soc. Civ. Eng.,1993,98: 418-433.
[3] Kotsubo S. Dynamic water Pressure on dams due to irregular earthquakes Memoirs Faculty of Engineering[J],Kyushu university,Fukuoka,Japan,1959,18(4):119-129.
[4] Chopra A. K . Hydrodynamic Pressure on dams during earthquakes[M]. J. Engng·Mech. Div,ASCE,1967,93(6):205一223.
[5]小平清真.不规则地震力所引起的坝上的动水压力[M].水利译丛,1958.
[6] H.Lamb. On the vibration of an elastic plate in contact with water proceedings of the royal society of London[J],1920,98-99.
[7] Blevins R. D. Flow一induced vibration[J]. Van Nostrand-Reinhold,New York,1977
[8] Haskind M D·The hydrodynamic theory of ship oscillations in rolling and Pitching[M]. Prikl,Mat,Mech,1946,10:33-66.
[9] Housner G. W. Bending vibrations of a pipe line containing flowing fluid[J]. Appl Mesh,1952,19:205-208.
[10] Taylor. GI. The pressure and impulse of submarine explosion waves on plates[M].In: Batchelor G K ed. The scientific Papers of. GI. Taylor,Cambridge University Press,Cambridge,1963.
[11]郑哲敏.平板在流体作用下的振动[J].力学学报,1958,(l):11-16.
[12]居荣初,曾心传.弹性结构与液体耦联振动理论[M].北京:地震出版社,1983.
[13]蒋莉,沈孟育.求解流体与结构相互作用问题的ALE有限体积法[J].水动力学研究与进展,2000,15(2):148-155.
[14] Zienkiewicz O C. Coupled Problems and their numerical solution [J]. In: Lewis R W,Bettess Phimton E eds. Numerical Methods in coupled system. John Wiley and Sons Ltd,New York,1984.
[15]刘正兴,孙雁,谢守国.流体介质中结构的动力特性及响应分析[J].上海交通大学学报,1995,29(4):7-16. [16〕Hirt C.W,Amsden A A,Cook J L An Arbitrary Lagrange-Euler computing Method for all flow speeds[J]. J.,of computational physics,1974,14(3):27-253.
[17] Bath K J,Zhang Hand Wang M H. Finite element analysis of incompressible and compressible flows with free surfaces and structural interaction[G]. Computers And structures,1995,56(2-3):293-213.
[18] A·T·Chwang and K.H. Wang. Nonlinear impulsive force on an accelerating container[J].Journal of Fluids Engineering,1954,106(2):223-240.
[19]李遇春,蒋梦麟.强震下流体对渡槽槽身的作用[J].水利学报,2000,3:46-52.
[20]惠明,赵德有.流固耦合振动问题的特征值解法[J].大连理工大学学报,1990,3:15-19.
[21]黄玉盈.复杂外形薄浮板谐耦振问题的边界元一有限元混和解[J].固体力学学报,1991,12(3):255-260.
[22]傅作新.水库的库底条件和挡水结构的动水压力[J].水利学报,1987,5:20-25.
[23]杜修力,陈厚群,侯顺载.拱坝系统三维非线性地震波动分析[J].地震工程与工程振动,1996,16(3):39-47.
[24]张升明,吴士冲.流固耦合有限元及储液容器振动问题研究[G].船舶结构力学论文集(二),1990.
[25]吴一红,谢省宗.水工结构流固耦合动力特性分析[J].水利学报,1995,1:27-34.
[26] S. Subhas Babu, S. K. Bhattacharyya. Finite Element Analysis Of Fluid-Structure Interaction Effect On Liquid Retaining Structures Due Tosloshing[G]. Computer&Structures,1996,Vol.59(6):1165-1171.
[27] A. K. Slone, et al. Dynamic fluid-structure interaction using finite volume unstructured mesh procedures [J].Computers and Structures, 2002, vol.80:371～390.
[28] Matej Vesenjak, Zoran Ren. Weakly coupled analysis of a blade in multiphase mixing vesse[J].Matjaz Hribersek,2004(4):378～379.
[29]袁启铭.轴流泵叶片流固耦合振动特性分析[D].扬州:扬州大学,2009.
[30]刘涛,杨凤鹏.精通ANSYS[M].北京:清华大学出版社,2002.
[31]高学平.高等流体力学.天津[M]:天津大学出版社,2005.
[32]陈香林.混流式水轮机叶片流固耦合动力特性研究[D].昆明:昆明理工大学, 2004.
[33]徐芝纶.弹性力学[M].北京:高等教育出版社,1990.
[34]张兆顺,崔桂香.流体力学[M].北京:清华大学出版社,1999.
[35]章本照.流体力学的有限元方法[M].北京:机械工业出版社,1986.
[36]黄克智,薛明德,陆明万.张量分析[M].北京:清华大学出版社,1986.
[37]朱伯芳.有限单元法原理与应用[M].北京:水利电力出版社,1979.
[38]王瑞金,张凯,王刚.Fluent技术基础与应用实例[M].北京:清华大学出版社,2007.
[2] Westergard H. M. Water Pressure on dams during earthquakes[M]. Trans. Amer Soc. Civ. Eng.,1993,98: 418-433.
[3] Kotsubo S. Dynamic water Pressure on dams due to irregular earthquakes Memoirs Faculty of Engineering[J],Kyushu university,Fukuoka,Japan,1959,18(4):119-129.
[4] Chopra A. K . Hydrodynamic Pressure on dams during earthquakes[M]. J. Engng·Mech. Div,ASCE,1967,93(6):205一223.
[5]小平清真.不规则地震力所引起的坝上的动水压力[M].水利译丛,1958.
[6] H.Lamb. On the vibration of an elastic plate in contact with water proceedings of the royal society of London[J],1920,98-99.
[7] Blevins R. D. Flow一induced vibration[J]. Van Nostrand-Reinhold,New York,1977
[8] Haskind M D·The hydrodynamic theory of ship oscillations in rolling and Pitching[M]. Prikl,Mat,Mech,1946,10:33-66.
[9] Housner G. W. Bending vibrations of a pipe line containing flowing fluid[J]. Appl Mesh,1952,19:205-208.
[10] Taylor. GI. The pressure and impulse of submarine explosion waves on plates[M].In: Batchelor G K ed. The scientific Papers of. GI. Taylor,Cambridge University Press,Cambridge,1963.
[11]郑哲敏.平板在流体作用下的振动[J].力学学报,1958,(l):11-16.
[12]居荣初,曾心传.弹性结构与液体耦联振动理论[M].北京:地震出版社,1983.
[13]蒋莉,沈孟育.求解流体与结构相互作用问题的ALE有限体积法[J].水动力学研究与进展,2000,15(2):148-155.
[14] Zienkiewicz O C. Coupled Problems and their numerical solution [J]. In: Lewis R W,Bettess Phimton E eds. Numerical Methods in coupled system. John Wiley and Sons Ltd,New York,1984.
[15]刘正兴,孙雁,谢守国.流体介质中结构的动力特性及响应分析[J].上海交通大学学报,1995,29(4):7-16. [16〕Hirt C.W,Amsden A A,Cook J L An Arbitrary Lagrange-Euler computing Method for all flow speeds[J]. J.,of computational physics,1974,14(3):27-253.
[17] Bath K J,Zhang Hand Wang M H. Finite element analysis of incompressible and compressible flows with free surfaces and structural interaction[G]. Computers And structures,1995,56(2-3):293-213.
[18] A·T·Chwang and K.H. Wang. Nonlinear impulsive force on an accelerating container[J].Journal of Fluids Engineering,1954,106(2):223-240.
[19]李遇春,蒋梦麟.强震下流体对渡槽槽身的作用[J].水利学报,2000,3:46-52.
[20]惠明,赵德有.流固耦合振动问题的特征值解法[J].大连理工大学学报,1990,3:15-19.
[21]黄玉盈.复杂外形薄浮板谐耦振问题的边界元一有限元混和解[J].固体力学学报,1991,12(3):255-260.
[22]傅作新.水库的库底条件和挡水结构的动水压力[J].水利学报,1987,5:20-25.
[23]杜修力,陈厚群,侯顺载.拱坝系统三维非线性地震波动分析[J].地震工程与工程振动,1996,16(3):39-47.
[24]张升明,吴士冲.流固耦合有限元及储液容器振动问题研究[G].船舶结构力学论文集(二),1990.
[25]吴一红,谢省宗.水工结构流固耦合动力特性分析[J].水利学报,1995,1:27-34.
[26] S. Subhas Babu, S. K. Bhattacharyya. Finite Element Analysis Of Fluid-Structure Interaction Effect On Liquid Retaining Structures Due Tosloshing[G]. Computer&Structures,1996,Vol.59(6):1165-1171.
[27] A. K. Slone, et al. Dynamic fluid-structure interaction using finite volume unstructured mesh procedures [J].Computers and Structures, 2002, vol.80:371～390.
[28] Matej Vesenjak, Zoran Ren. Weakly coupled analysis of a blade in multiphase mixing vesse[J].Matjaz Hribersek,2004(4):378～379.
[29]袁启铭.轴流泵叶片流固耦合振动特性分析[D].扬州:扬州大学,2009.
[30]刘涛,杨凤鹏.精通ANSYS[M].北京:清华大学出版社,2002.
[31]高学平.高等流体力学.天津[M]:天津大学出版社,2005.
[32]陈香林.混流式水轮机叶片流固耦合动力特性研究[D].昆明:昆明理工大学, 2004.
[33]徐芝纶.弹性力学[M].北京:高等教育出版社,1990.
[34]张兆顺,崔桂香.流体力学[M].北京:清华大学出版社,1999.
[35]章本照.流体力学的有限元方法[M].北京:机械工业出版社,1986.
[36]黄克智,薛明德,陆明万.张量分析[M].北京:清华大学出版社,1986.
[37]朱伯芳.有限单元法原理与应用[M].北京:水利电力出版社,1979.
[38]王瑞金,张凯,王刚.Fluent技术基础与应用实例[M].北京:清华大学出版社,2007.