非均匀进流下喷水推进泵进流速度场的数值分析
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摘要
为具体描述喷水推进泵非均匀进流的结构特点,并深入探究非均匀流对喷水推进泵性能的影响,运用CFD-Post软件提取进水流道的出流速度场,将其Profile Data文件定义为喷水推进泵的附加进流条件,数值计算非均匀进流下泵的水动力性能,并与均匀进流下的仿真结果进行比较,获得了喷水推进泵扬程和效率的降幅曲线,其下降幅值随进流场不均匀度的增大而上升.围绕喷水推进泵叶轮进口边的周向平均速度分量,具体分析泵在非均匀进流场中性能下降的原因.结果表明,喷水推进泵的传统设计方法无法满足实际工作要求,相关假设在非均匀进流中也不再适用.其中,非均匀进流场中进口预旋不可忽略;叶轮进口轴面速度和环量不再遵循线性分布规律;圆柱面无关假设也不再成立.非均匀进流对叶轮的干扰集中于叶片进口轮缘处,二次回流的出现堵塞了流道,降低了泵的过流能力,同时诱发叶片轮缘处的载荷突变,降低了泵的做功能力.
To research the correlation between non-uniform inflow and the hydrodynamics of water-jet pump,the outflow velocity field in the intake duct was analyzed by CFX- Post software. The velocity field of non-uniform outflow was selected as the inflow boundary condition in the process of simulation,and the hydrodynamics of water-jet pump was achieved. Then the comparison of hydrodynamics between non-uniform and uniform inflow conditions was carried out. The results show that the hydrodynamics of water-jet pump under the non-uniform inflow condition is lower than that under the uniform inflow condition. With the non-uniformity of the inflow field increasing,the decreasing amplitude of the head and efficiency is increasing. According to velocity components of non-uniform,the reason thatthe pump hydrodynamics reduced under the non-uniform inflow condition was analyzed. The results show that the traditional design method does not meet the working requirements,and the correlation assumptions are unavailable to the condition of non-uniform inflow. The existence of inlet pre-swirling in the non-uniform inflow field is against the " no pre-swirling" hypothesis,so the angle of attack and the lift coefficient of airfoils decrease. The interaction between axial and radial velocity in the non-uniform inflow field results in the nonlinear distribution of the meridional velocity and circulation. The circumference independence assumption is invalid owing to the change of radial velocity. The non-uniform inflow also impacts the field of blades,which is concentrated at the shroud. The secondary circumfluence blocks the flow passages,and weakens the flow capacity of the water-jet pump. Meanwhile,it contributes to the deviation curve of blade loading at the shroud,and impairs the working ability of the waterjet pump. In conclusion,the non-uniform inflow is the major reason for the decrement of propulsion efficiency,therefore the non-uniform inflow condition should be considered during the process of water-jet pump designing.
To research the correlation between non-uniform inflow and the hydrodynamics of water-jet pump,the outflow velocity field in the intake duct was analyzed by CFX- Post software. The velocity field of non-uniform outflow was selected as the inflow boundary condition in the process of simulation,and the hydrodynamics of water-jet pump was achieved. Then the comparison of hydrodynamics between non-uniform and uniform inflow conditions was carried out. The results show that the hydrodynamics of water-jet pump under the non-uniform inflow condition is lower than that under the uniform inflow condition. With the non-uniformity of the inflow field increasing,the decreasing amplitude of the head and efficiency is increasing. According to velocity components of non-uniform,the reason thatthe pump hydrodynamics reduced under the non-uniform inflow condition was analyzed. The results show that the traditional design method does not meet the working requirements,and the correlation assumptions are unavailable to the condition of non-uniform inflow. The existence of inlet pre-swirling in the non-uniform inflow field is against the " no pre-swirling" hypothesis,so the angle of attack and the lift coefficient of airfoils decrease. The interaction between axial and radial velocity in the non-uniform inflow field results in the nonlinear distribution of the meridional velocity and circulation. The circumference independence assumption is invalid owing to the change of radial velocity. The non-uniform inflow also impacts the field of blades,which is concentrated at the shroud. The secondary circumfluence blocks the flow passages,and weakens the flow capacity of the water-jet pump. Meanwhile,it contributes to the deviation curve of blade loading at the shroud,and impairs the working ability of the waterjet pump. In conclusion,the non-uniform inflow is the major reason for the decrement of propulsion efficiency,therefore the non-uniform inflow condition should be considered during the process of water-jet pump designing.
引文
[1]BULTEN N.A breakthrough in waterjet propulsion systems[C]//Proceedings of International Maritime Defence Exhibition and Conference.Doha,Qatar:DIMDEX,2008.
[2]ZANGENEH M,DANESHKHAH K,DACOSTA B.A multi-objective automatic optimization strategy for design of water-jet pumps[C]//Proceedings of International Conference of Water-jet Propulsion—V.London:RINA,2008.
[3]ALLISON J L.Model tools for water-jet pump design and research advances in the field[C]//Proceedings of International Conference on Water-jet Propulsion—Ⅱ.London:RINA,2004.
[4]常书平,王永生,苏永生.若干因素对导叶式混流泵水力性能的影响[J].排灌机械工程学报,2012,30(6):646-649.CHANG Shuping,WANG Yongsheng,SU Yongsheng.Effects of some factors on hydraulic performance of mixed-flow pump with guide vanes[J].Journal of drainage and irrigation machinery engineering,2012,30(6):646-649.(in Chinese)
[5]DUCCIO B,MEHRDAD Z,REIMA A J E.Parametric design of a waterjet pump by means of inverse design CFD calculations and experimental analyses[J].Journal of fluid engineering,2010,132(3):031104.
[6]TAYLOR T E,KERWIN J E,SCHERER J O.Waterjet pump design and analysis using a coupled lifting-surface and RANS procedure[C]//Proceedings of International Conference on Water-jet Propulsion—Ⅱ.Amsterdam,Netherland,1998.
[7]施卫东,张光建,吴苏青,等.入口非均匀流对轴流泵性能和压力脉动的影响[J].排灌机械工程学报,2014,32(4):277-282.SHI Weidong,ZHANG Guangjian,WU Suqing,et al.Effect of non-uniform suction flow on performance and pressure fluctuation in axial flow pump[J].Journal of drainage and irrigation machinery engineering,2014,32(4):277-282.(in Chinese)
[8]BULTEN N W H.Numerical analysis of waterjet propulsion system[D].Eindhoven:Technical University of Eindhoven,2006.
[9]王永生,魏应三.喷水推进器进水流道不均匀度统一描述[J].武汉理工大学学报,2009,31(8):159-163.WANG Yongsheng,WEI Yingsan.Unified description of outflow non-uniformity of waterjet duct[J].Journal of Wuhan University of Technology,2009,31(8):159-163.(in Chinese)
[10]刘瑞华,曹璞钰,王洋,等.无轴式喷水推进泵的水动力特性[J].排灌机械工程学报,2015,33(5):380-386.LIU Ruihua,CAO Puyu,WANG Yang,et al.Hydrodynamic characteristics of shaft-less waterjet pump[J].Journal of drainage and irrigation machinery engineering,2015,33(5):380-386.(in Chinese)
[11]金平仲,曾松祥,王立祥,等.船舶喷水推进及轴流式推进泵论文集[C].上海:中国船舶工业集团公司第708研究所,1991.
[12]关醒凡.现代泵技术手册[M].北京:中国宇航出版社,1995.
[13]朗继先.轴流泵变轴面速度流型设计理论的研究[J].北京农业工程大学学报,1987,7(4):47-55.LANG Jixian.The variable meridional velocity flowpattern design theory for axial-flow pump[J].Journal of Beijing Agricultural Engineering University,1987,7(4):47-55.(in Chinese)
[14]BONAIUTI D,ZANGENEH M,AARTOJARVI R,et al.Parametric design of a waterjet pump by means of inverse design,CFD calculation and experimental analyses[J].Journal of turbomachinery,2010,132(3):1-15.
[15]常书平,王永生,靳栓宝,等.载荷分布规律对混流泵叶轮设计的影响[J].排灌机械工程学报,2013,31(2):124-128.CHANG Shuping,WANG Yongsheng,JIN Shuanbao,et al.Influences of blade loading distribution law on design of mixed-flow pump impeller[J].Journal of drainage and irrigation machinery engineering,2013,31(2):124-128.(in Chinese)
[2]ZANGENEH M,DANESHKHAH K,DACOSTA B.A multi-objective automatic optimization strategy for design of water-jet pumps[C]//Proceedings of International Conference of Water-jet Propulsion—V.London:RINA,2008.
[3]ALLISON J L.Model tools for water-jet pump design and research advances in the field[C]//Proceedings of International Conference on Water-jet Propulsion—Ⅱ.London:RINA,2004.
[4]常书平,王永生,苏永生.若干因素对导叶式混流泵水力性能的影响[J].排灌机械工程学报,2012,30(6):646-649.CHANG Shuping,WANG Yongsheng,SU Yongsheng.Effects of some factors on hydraulic performance of mixed-flow pump with guide vanes[J].Journal of drainage and irrigation machinery engineering,2012,30(6):646-649.(in Chinese)
[5]DUCCIO B,MEHRDAD Z,REIMA A J E.Parametric design of a waterjet pump by means of inverse design CFD calculations and experimental analyses[J].Journal of fluid engineering,2010,132(3):031104.
[6]TAYLOR T E,KERWIN J E,SCHERER J O.Waterjet pump design and analysis using a coupled lifting-surface and RANS procedure[C]//Proceedings of International Conference on Water-jet Propulsion—Ⅱ.Amsterdam,Netherland,1998.
[7]施卫东,张光建,吴苏青,等.入口非均匀流对轴流泵性能和压力脉动的影响[J].排灌机械工程学报,2014,32(4):277-282.SHI Weidong,ZHANG Guangjian,WU Suqing,et al.Effect of non-uniform suction flow on performance and pressure fluctuation in axial flow pump[J].Journal of drainage and irrigation machinery engineering,2014,32(4):277-282.(in Chinese)
[8]BULTEN N W H.Numerical analysis of waterjet propulsion system[D].Eindhoven:Technical University of Eindhoven,2006.
[9]王永生,魏应三.喷水推进器进水流道不均匀度统一描述[J].武汉理工大学学报,2009,31(8):159-163.WANG Yongsheng,WEI Yingsan.Unified description of outflow non-uniformity of waterjet duct[J].Journal of Wuhan University of Technology,2009,31(8):159-163.(in Chinese)
[10]刘瑞华,曹璞钰,王洋,等.无轴式喷水推进泵的水动力特性[J].排灌机械工程学报,2015,33(5):380-386.LIU Ruihua,CAO Puyu,WANG Yang,et al.Hydrodynamic characteristics of shaft-less waterjet pump[J].Journal of drainage and irrigation machinery engineering,2015,33(5):380-386.(in Chinese)
[11]金平仲,曾松祥,王立祥,等.船舶喷水推进及轴流式推进泵论文集[C].上海:中国船舶工业集团公司第708研究所,1991.
[12]关醒凡.现代泵技术手册[M].北京:中国宇航出版社,1995.
[13]朗继先.轴流泵变轴面速度流型设计理论的研究[J].北京农业工程大学学报,1987,7(4):47-55.LANG Jixian.The variable meridional velocity flowpattern design theory for axial-flow pump[J].Journal of Beijing Agricultural Engineering University,1987,7(4):47-55.(in Chinese)
[14]BONAIUTI D,ZANGENEH M,AARTOJARVI R,et al.Parametric design of a waterjet pump by means of inverse design,CFD calculation and experimental analyses[J].Journal of turbomachinery,2010,132(3):1-15.
[15]常书平,王永生,靳栓宝,等.载荷分布规律对混流泵叶轮设计的影响[J].排灌机械工程学报,2013,31(2):124-128.CHANG Shuping,WANG Yongsheng,JIN Shuanbao,et al.Influences of blade loading distribution law on design of mixed-flow pump impeller[J].Journal of drainage and irrigation machinery engineering,2013,31(2):124-128.(in Chinese)