动态调速工况液力偶合器瞬态流场PIV试验
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摘要
为了分析大功率液力偶合器在调速工况中能容下降、效率降低及输出特性失稳等问题产生的原因,建立了液力偶合器内/外特性同步测试试验台,采用PIV(粒子图像测速)流场测试的方法分析动态调速工况下偶合器涡轮内部瞬态流动特性.将动态调速与对应稳态工况在径向/轴向切面的流场测试对比,结果表明:在环流转换的调速过渡区间内,受气相的干扰流道中部出现较大的低速区,与对应稳态工况流场差别较大;在额定工况附近及其他调速工况点,速度流场变化趋势与稳态工况相当;随着动态调速工况转速差的增加,在轴向切面内显示多尺度气泡弥散在液相中并随着液体质点做螺旋运动,在涡轮入口吸力面附近逐渐出现大面积的低速区且其分布区域逐渐增大,最终在速度梯度较大的涡轮入口靠近吸力面处形成主漩涡.
In order to analyze the causes of the problems such as the decline of energy capacity,the decrease of efficiency and the instability of the output characteristics of the high-power hydraulic coupler in the speed regulation condition,the internal/external characteristic synchronous test bench of the fluid coupling was established.The PIV(particle image velocimetry) flow field test method was used to study the transient flow characteristics of the coupling turbine under dynamic speed control conditions.By comparing the dynamic speed regulation with the flow field measurement in the radial/axial section of the corresponding steady state condition,results show that in the transition zone of the circulation conversion,there is a large low speed zone in the middle of the flow passage disturbed by the gas phase,which is quite different from the flow field under the corresponding steady state condition;the speed flow field change trend is similar to the steady state condition in the vicinity of the rated working condition and other speed regulating working conditions.With the increase of the rotational speed difference in the dynamic speed regulation condition,the multi-scale bubble is dispersed in the liquid phase in the axial section and the complex spiral motion is performed with the liquid particle,and a large-area low-speed zone gradually appears near the inlet suction surface of the turbine,whose distribution area gradually increases,and finally the main vortex is formed near the suction surface at the turbine inlet with a large velocity gradient.
In order to analyze the causes of the problems such as the decline of energy capacity,the decrease of efficiency and the instability of the output characteristics of the high-power hydraulic coupler in the speed regulation condition,the internal/external characteristic synchronous test bench of the fluid coupling was established.The PIV(particle image velocimetry) flow field test method was used to study the transient flow characteristics of the coupling turbine under dynamic speed control conditions.By comparing the dynamic speed regulation with the flow field measurement in the radial/axial section of the corresponding steady state condition,results show that in the transition zone of the circulation conversion,there is a large low speed zone in the middle of the flow passage disturbed by the gas phase,which is quite different from the flow field under the corresponding steady state condition;the speed flow field change trend is similar to the steady state condition in the vicinity of the rated working condition and other speed regulating working conditions.With the increase of the rotational speed difference in the dynamic speed regulation condition,the multi-scale bubble is dispersed in the liquid phase in the axial section and the complex spiral motion is performed with the liquid particle,and a large-area low-speed zone gradually appears near the inlet suction surface of the turbine,whose distribution area gradually increases,and finally the main vortex is formed near the suction surface at the turbine inlet with a large velocity gradient.
引文
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[5]CHRISTEN M,KERNCHEN R.Fluid velocity in of constant fill turbo couplings:measurements using laser Doppler velocimetry[J].Antriebstechnik,2001,40:71-74.
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[8]才委,马文星,刘春宝,等.液力变矩器泵轮内部流动PIV测试与分析[J].江苏大学学报:自然科学版,2014,35(3):274-278.
[9]柴博森,刘春宝,王卫东.基于霍夫变换的液力变矩器泵轮内部流速提取[J].排灌机械工程学报,2014,32(4):283-289.
[10]柴博森,王玉建,刘春宝,等.基于粒子图像测速技术的液力变矩器涡轮内流场测试与分析[J].农业工程学报,2015,31(12):92-98.
[11]柴博森,项玥,马文星,等.制动工况下液力偶合器流场湍流模型分析与验证[J].农业工程学报,2016,32(3):34-40.
[12]柴博森,项玥,马文星,等.液力偶合器漩涡流场PIV试验测量影响因素分析[J].华南理工大学学报:自然科学版,2017,45(12):92-98.
[13]李志峰,吴大转,戴维平,等.离心泵启动过程瞬态特性与流动的实验研究[J].工程热物理学报,2010,31(12):2019-2022.
[2]BAI L,FIEBIG M,MITRA N K.Numerical analysis of turbulent flow in fluid couplings[J].Journal of Fluids Engineering,1997,119(3):569-576.
[3]何延东,马文星,刘春宝.液力偶合器部分充液流场数值模拟与特性计算[J].农业机械学报,2009,40(5):24-28.
[4]赵继云,张德生.液力偶合器气液界面追踪数值模拟[J].机械工程学报,2012,48(4):182-187.
[5]CHRISTEN M,KERNCHEN R.Fluid velocity in of constant fill turbo couplings:measurements using laser Doppler velocimetry[J].Antriebstechnik,2001,40:71-74.
[6]HAMPELA U,HOPPEA D,DIELEB K H,et al.Application of gamma tomography to the measurement of fluid distributions in a hydrodynamic coupling[J].Flow Measurement and Instrumentation,2005(16):177-182.
[7]SILVA M J D,LU Y,SUHNEL T.Autonomous planar conductivity array sensor for fast liquid distribution imaging in a fluid coupling[J].Sensors&Actuators A:Physical,2008,147(2):508-515.
[8]才委,马文星,刘春宝,等.液力变矩器泵轮内部流动PIV测试与分析[J].江苏大学学报:自然科学版,2014,35(3):274-278.
[9]柴博森,刘春宝,王卫东.基于霍夫变换的液力变矩器泵轮内部流速提取[J].排灌机械工程学报,2014,32(4):283-289.
[10]柴博森,王玉建,刘春宝,等.基于粒子图像测速技术的液力变矩器涡轮内流场测试与分析[J].农业工程学报,2015,31(12):92-98.
[11]柴博森,项玥,马文星,等.制动工况下液力偶合器流场湍流模型分析与验证[J].农业工程学报,2016,32(3):34-40.
[12]柴博森,项玥,马文星,等.液力偶合器漩涡流场PIV试验测量影响因素分析[J].华南理工大学学报:自然科学版,2017,45(12):92-98.
[13]李志峰,吴大转,戴维平,等.离心泵启动过程瞬态特性与流动的实验研究[J].工程热物理学报,2010,31(12):2019-2022.