空气自由射流能量分离的数值模拟
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摘要
为了探究能量合理利用形式,以空气自由射流为研究对象,考虑粘性及导热条件,基于无量纲湍流控制方程,采用数值模拟手段,考察了亚音速(100、200、300 m/s)下空气自由射流的能量分离现象以及雷诺数对空气自由射流能量分离的影响。研究结果表明:空气自由射流边界层外存在高低温区域共存现象;当自由射流速度处于亚音速范围内时,雷诺数越大,能量分离效应越强。研究证实了空气自由射流边界层外存在的能量分离现象,揭示了流体领域内能量分离的机理。
To explore the rational energy utilization form, free air jet was chosen as the object of study. In view of viscosity and heat transfer conditions and on the basis of dimensionless turbulence control equations, numerical simulation was used to investigate the energy separation of free air jet under subsonic flow conditions(i.e., velocities of 100, 200 and 300 m/s, respectively), and the influence of Reynolds number on the energy separation. The analysis result showed the co-existence of high temperature region and low temperature region outside the boundary layer of free air jet. The bigger the Reynolds number is, the stronger the energy separation effect is within the subsonic range. This paper confirms the existence of energy separation outside the boundary layer of free air jet and reveals the mechanism of energy separation in the fluid field.
To explore the rational energy utilization form, free air jet was chosen as the object of study. In view of viscosity and heat transfer conditions and on the basis of dimensionless turbulence control equations, numerical simulation was used to investigate the energy separation of free air jet under subsonic flow conditions(i.e., velocities of 100, 200 and 300 m/s, respectively), and the influence of Reynolds number on the energy separation. The analysis result showed the co-existence of high temperature region and low temperature region outside the boundary layer of free air jet. The bigger the Reynolds number is, the stronger the energy separation effect is within the subsonic range. This paper confirms the existence of energy separation outside the boundary layer of free air jet and reveals the mechanism of energy separation in the fluid field.
引文
[1] Han B,Goldstein R J.A numerical study of energy separation in a jet flow[J].Journal of Heat Transfer,2007,129(4):577-581.
[2] 张国庆,吴玉庭,丁雨,等.不同气体对涡流管能量分离效果的影响[J].航空动力学报,2008(1):134-137.
[3] 李文超.基于涡流管的能量分离模拟研究[J].管道技术与设备,2018(4):50-52.
[4] 祁海鹰,黄兴亮,胡羽,等.龙卷旋涡的真空与能量分离特性研究[J].清华大学学报(自然科学版),2016,56(8):893-907.
[5] 汤振豪,余晓明,丁义萍.喷嘴结构对涡流管性能影响的研究[J].低温与超导,2018,46(6):96-100.
[6] 何丽娟,潘鹏,黄艳伟,等.三维数值模拟冷孔板孔径对涡流管能量分离特性的影响[J].真空科学与技术学报,2018,38(3):252-257.
[7] 李俐莹,刘晓明,邹积岩.高压SF_6断路器能量分离喷口区域的气流参数特性[J].高电压技术,2015,41(9):3123-3129.
[8] Eckert E R G,Drewitz O.Die berechnung des temperaturfeldes in der laminaren grenzschicht schnell angestr?mter,unbeheizter k?rper[J].Luftfahrtfordchung,1941,19:189-196.
[9] Eckert E R G,Weise W.Messungen der temperaturverteilung auf der oberfl?che schnell angestr?mter unbeheizter k?rper[J].Forschung Auf Dem Gebiet Des Ingenieurwesens A,1942,13(6):246-254.
[10] Goldstein R J,He B.Energy separation and acoustic interaction in flow across a circular cylinder[J].Acta Pathologica Et Microbiologica Scandinavica,2001,62(4):107-11.
[11] Seol W S,Goldstein R J.Energy separation in a jet flow[J].Journal of Fluids Engineering,1997,119(1):74-82.
[12] Goldstein R J,Behbahani A I,Heppelmann K K.Streamwise distribution of the recovery factor and the local heat transfer coefficient to an impinging circular air jet[J].International Journal of Heat and Mass Transfer,1986,29(8):1227-1235.
[13] Goldstein R J,Sobolik K A,Seol W S.Effect of entrainment on the heat transfer to a heated circular air jet impinging on a flat surface[J].Journal of Heat Transfer,1990,112(3):608-611.
[14] Han B.Instantaneous Energy Separation in a Jet Flow[D].Minnesota:University of Minnesota,2001:52-62.
[15] Fox M D,Kurosaka M.Supersonic cooling by shock–vortex interaction[J].Journal of Fluid Mechanics,1996,308:363-379.
[16] Leontiev A I,Zditovets A G,Vinogradov Y A,et al.Experimental investigation of the machine-free method of temperature separation of air flows based on the energy separation effect in a compressible boundary layer[J].Experimental Thermal and Fluid Science,2017,88:202-219.
[17] Fox M D,Kurosaka M,Hedges L,et al.The influence of vortical structures on the thermal fields of jets[J].Journal of Fluid Mechanics,1993,255:447-472.
[18] Han B,Goldstein R J,Choi H G.Energy separation in shear layers[J].International Journal of Heat & Mass Transfer,2002,45(1):47-55.
[19] Eckert E R G.Energy separation in fluid streams[J].International Communications in Heat & Mass Transfer,1986,13(2):127-143.
[20] Kulkarni K S,Goldstein R J.Energy separation in the wake of a cylinder:Effect of Reynolds number and acoustic resonance[J].International Journal of Heat & Mass Transfer,2009,52(17):3994-4000.
[2] 张国庆,吴玉庭,丁雨,等.不同气体对涡流管能量分离效果的影响[J].航空动力学报,2008(1):134-137.
[3] 李文超.基于涡流管的能量分离模拟研究[J].管道技术与设备,2018(4):50-52.
[4] 祁海鹰,黄兴亮,胡羽,等.龙卷旋涡的真空与能量分离特性研究[J].清华大学学报(自然科学版),2016,56(8):893-907.
[5] 汤振豪,余晓明,丁义萍.喷嘴结构对涡流管性能影响的研究[J].低温与超导,2018,46(6):96-100.
[6] 何丽娟,潘鹏,黄艳伟,等.三维数值模拟冷孔板孔径对涡流管能量分离特性的影响[J].真空科学与技术学报,2018,38(3):252-257.
[7] 李俐莹,刘晓明,邹积岩.高压SF_6断路器能量分离喷口区域的气流参数特性[J].高电压技术,2015,41(9):3123-3129.
[8] Eckert E R G,Drewitz O.Die berechnung des temperaturfeldes in der laminaren grenzschicht schnell angestr?mter,unbeheizter k?rper[J].Luftfahrtfordchung,1941,19:189-196.
[9] Eckert E R G,Weise W.Messungen der temperaturverteilung auf der oberfl?che schnell angestr?mter unbeheizter k?rper[J].Forschung Auf Dem Gebiet Des Ingenieurwesens A,1942,13(6):246-254.
[10] Goldstein R J,He B.Energy separation and acoustic interaction in flow across a circular cylinder[J].Acta Pathologica Et Microbiologica Scandinavica,2001,62(4):107-11.
[11] Seol W S,Goldstein R J.Energy separation in a jet flow[J].Journal of Fluids Engineering,1997,119(1):74-82.
[12] Goldstein R J,Behbahani A I,Heppelmann K K.Streamwise distribution of the recovery factor and the local heat transfer coefficient to an impinging circular air jet[J].International Journal of Heat and Mass Transfer,1986,29(8):1227-1235.
[13] Goldstein R J,Sobolik K A,Seol W S.Effect of entrainment on the heat transfer to a heated circular air jet impinging on a flat surface[J].Journal of Heat Transfer,1990,112(3):608-611.
[14] Han B.Instantaneous Energy Separation in a Jet Flow[D].Minnesota:University of Minnesota,2001:52-62.
[15] Fox M D,Kurosaka M.Supersonic cooling by shock–vortex interaction[J].Journal of Fluid Mechanics,1996,308:363-379.
[16] Leontiev A I,Zditovets A G,Vinogradov Y A,et al.Experimental investigation of the machine-free method of temperature separation of air flows based on the energy separation effect in a compressible boundary layer[J].Experimental Thermal and Fluid Science,2017,88:202-219.
[17] Fox M D,Kurosaka M,Hedges L,et al.The influence of vortical structures on the thermal fields of jets[J].Journal of Fluid Mechanics,1993,255:447-472.
[18] Han B,Goldstein R J,Choi H G.Energy separation in shear layers[J].International Journal of Heat & Mass Transfer,2002,45(1):47-55.
[19] Eckert E R G.Energy separation in fluid streams[J].International Communications in Heat & Mass Transfer,1986,13(2):127-143.
[20] Kulkarni K S,Goldstein R J.Energy separation in the wake of a cylinder:Effect of Reynolds number and acoustic resonance[J].International Journal of Heat & Mass Transfer,2009,52(17):3994-4000.