层流脉动流动强化换热的实验研究
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摘要
随着科学技术的不断发展,能源环境等问题也不断的出现,如何更好的利用能源,提高能源的利用率得到了越来越多人的重视。强化传热技术作为提高换热效率的主要方式在能源节约中起着非常重要的作用,已经成为各国学者研究的一个方向。脉动流动技术作为强化换热技术的一个主要方式已经被人们用数值和实验方法证实。
本文采用实验的方法对三角槽通道内层流脉动流动强化换热进行研究,分析了不同雷诺数Re,斯德鲁哈尔数St,脉动振幅A以及三角槽通道的槽深(6mm,9mm和12mm)对强化换热的影响。
结果表明脉动扰动显著地提高了三角槽通道的传热能力。稳态时,努赛尔数随着雷诺数的增大而增大,努赛尔数随着三角槽深度的增加先增大后减小；脉动时,传热强化因子随着雷诺数和脉动振幅的增加而增加。而当雷诺数和脉动振幅一定时,强化传热因子随着斯特鲁哈尔数的增大先增加后减小,存在一个使强化传热因子达到最大的最佳斯特鲁哈尔数,并且对于不同的雷诺数和脉动振幅使强化传热因子达到最大的脉动频率是相同的。当三角槽的槽深为12mm时,强化传热因子最大,而当槽深为9mm时,强化传热因子最小。三角槽的槽深对最佳斯特鲁哈尔数没有影响。压力梯度的脉动振幅随着雷诺数,脉动振幅的增大而增大,随着脉动频率的增大而减小
With the continuous development of science and technology, many problems have been emerged, especially in energy and environment. How to make better use of energy and improve the energy utilization have attracted more and more attention. Heat transfer enhancement as a major method of improving heat efficiency plays an important role in energy saving, which has been investigated by the researches all over the world. Pulsating flow as a main way of heat transfer enhancement has numerically and experimentally confirmed.
Heat transfer enhancement by laminar pulsating flow in triangular grooved channels was experimentally investigated by taking various factors into consideration, such as, Reynolds number, Strouhal number, pulsation amplitude and groove depth (6mm,9mm and12mm).
The results show that pulsating flow agitation promotes the heat transfer in triangular grooved channels. In steady flow case, Nusselt number increases as the Reynolds number increases, and it increases at first and then decrease with the increase of groove depth. In pulsating flow case, the heat transfer enhancement factor is improved with the increase of Reynolds number and pulsation amplitude. And the heat transfer enhancement factor increases firstly and then decreases with the increase of Strouhal number. There exists an optimal Strouhal number corresponding to the maximum heat transfer enhancement factor. The Reynolds number and pulsation amplitude have no effect on the optimal pulsation frequency. The heat transfer enhancement factor gets the maximum value when the groove channel depth is12mm and reaches the minimum value when the depth is9mm. And the groove channel depth has no influence on the optimum Strouhal number. The amplitude of pressure gradient increases with the increase of Reynolds number and pulsation amplitude, and decreases with the increase of pulsation frequency.
本文采用实验的方法对三角槽通道内层流脉动流动强化换热进行研究,分析了不同雷诺数Re,斯德鲁哈尔数St,脉动振幅A以及三角槽通道的槽深(6mm,9mm和12mm)对强化换热的影响。
结果表明脉动扰动显著地提高了三角槽通道的传热能力。稳态时,努赛尔数随着雷诺数的增大而增大,努赛尔数随着三角槽深度的增加先增大后减小；脉动时,传热强化因子随着雷诺数和脉动振幅的增加而增加。而当雷诺数和脉动振幅一定时,强化传热因子随着斯特鲁哈尔数的增大先增加后减小,存在一个使强化传热因子达到最大的最佳斯特鲁哈尔数,并且对于不同的雷诺数和脉动振幅使强化传热因子达到最大的脉动频率是相同的。当三角槽的槽深为12mm时,强化传热因子最大,而当槽深为9mm时,强化传热因子最小。三角槽的槽深对最佳斯特鲁哈尔数没有影响。压力梯度的脉动振幅随着雷诺数,脉动振幅的增大而增大,随着脉动频率的增大而减小
With the continuous development of science and technology, many problems have been emerged, especially in energy and environment. How to make better use of energy and improve the energy utilization have attracted more and more attention. Heat transfer enhancement as a major method of improving heat efficiency plays an important role in energy saving, which has been investigated by the researches all over the world. Pulsating flow as a main way of heat transfer enhancement has numerically and experimentally confirmed.
Heat transfer enhancement by laminar pulsating flow in triangular grooved channels was experimentally investigated by taking various factors into consideration, such as, Reynolds number, Strouhal number, pulsation amplitude and groove depth (6mm,9mm and12mm).
The results show that pulsating flow agitation promotes the heat transfer in triangular grooved channels. In steady flow case, Nusselt number increases as the Reynolds number increases, and it increases at first and then decrease with the increase of groove depth. In pulsating flow case, the heat transfer enhancement factor is improved with the increase of Reynolds number and pulsation amplitude. And the heat transfer enhancement factor increases firstly and then decreases with the increase of Strouhal number. There exists an optimal Strouhal number corresponding to the maximum heat transfer enhancement factor. The Reynolds number and pulsation amplitude have no effect on the optimal pulsation frequency. The heat transfer enhancement factor gets the maximum value when the groove channel depth is12mm and reaches the minimum value when the depth is9mm. And the groove channel depth has no influence on the optimum Strouhal number. The amplitude of pressure gradient increases with the increase of Reynolds number and pulsation amplitude, and decreases with the increase of pulsation frequency.
引文
[1]杨世铭,陶文铨.传热学第3版[M].北京：高等教育出版社,1998.
[2]王补宣.工程传热学[M].北京：科学出版社,1998.
[3]崔海亭,彭培英.强化传热新技术及其应用[M].北京：化学工业出版社,2006.
[4]阎浩峰,甘永平.新型换热器与传热强化[M].北京：宇航出版社,1991.
[5]朱聘冠.换热器原理与计算[M].北京：清华大学出版社,1987.
[6]秦叔经,叶文邦.换热器[M].北京：化学工业出版社,2003.
[7]朱冬生,钱颂文.强化传热技术及其设计应用[J].化工装备技术,2000,6：3-11.
[8]Wickramasinghe S R, Han B, Garcia J D, et al. Microporous membrane blood oxygenators[J].AIChE Journal,2005,51 (2):656-670.
[9]Beskok, Warburton T C. Arbitrary Lagrangian Eulerian Analysis of a Bidirectional Micro-Pump Using Spectral Elements [J]. Int. J. Comput. Eng. Sci.2001,2(1):43-57.
[10]Yi M, Bau H H, Hu H. A Peristaltic Meso-Scale Mixer[C]. ASME-IMECE.2000, MEMS 2, Orlando, FL,2000,367-374.
[11]Sert C, Beskok A. Oscillatory Flow Forced Convection in Micro Heat Spreaders [J]. Numer. Heat Transfer, Part A,2002,42 (7):685-705.
[12]Kim S Y, Kang B H, Hyun J M. Forced convection heat transfer from two heated blocks in pulsating channel flow[J]. Int. J. Heat Mass Transfer,1998,41:625-634.
[13]Bergles A E. The influence of flow vibrations on forced-convection heat transfer[J]. J. Heat Transfer,1964,7(1):102-106.
[14]Bergles A E, Newell P H. The influence of ultrasonic vibrations on heattransfer to waterflowing in annuli[J]. Int. J. Heat Transfer,1965,8:1273-1280.
[15]Jackon T W, Purdy K R. Resonant pulsating flow and convective heat transfer[J]. J. Heat Transfer,1965,87 (4):507-512.
[16]Nishimura T, Oka N, Yoshinaka Y, et al. Influence of imposed oscillatory frequency on mass transfer enhancement of grooved channels for pulsatile flow[J]. Int. J. Heat Mass Transfer,2000,43(13):2365-2374.
[17]Kunitsugu K, Nishimura T, Tanoue K. Mass transfer enhancement by pulsatile flows in grooved channels (The effects of groove length on the resonant mass transfer enhancement) [J]. Heat Transfer—Asian research,2008,37 (4):240-257.
[18]Greiner M. An experimental investigation of resonant heat transfer heat transfer enhancement in grooved channels [J]. Int. J. Heat Mass Transfer,1991,34:1383-1391.
[19]Yu J C., Li Z X., Zhao T S. An analytical study of pulsating laminar heat convection in a circular tube with constant heat flux[J]. Int. J. Heat Mass Transfer,2004, 47:5297-5301.
[20]Jin D X, Lee Y P, Lee D Y. Effects of the pulsating flow agitation on the heat transfer in a triangular grooved channel[J]. Int. J. Heat Mass Transfer,2007,50:3062-3071.
[21]Nishamura T, Ohori Y. Flow chatacteristics in a channel with symmetric wavy wall for steay flow[J]. J. Chem. Eng. Japan,1984, 17:466-471.
[22]Nishimura T, Kojima N. Mass transfer enhancement in a symmetric sinusoidal wavy-walled channel for pulsatile flow[J]. Int J Heat Mass Transfer,1995,38(10):1719-1731.
[23]Habib M A,Attya A M. Convective heat transfer characteristics of laminar pulsating pipe air flow[J].Heat and Mass Transfer,2002,38:221-232.
[24]Ghaddar N K, K Z Korczak, Mikic B B, et al. Numerical investigation of incompressible flow in grooved channels. Part 1:Stability and self-sustained oscillations[J]. J. Fluid Mech.,1986,163:99-127.
[25]Ghaddar N K, Magen M, Mikic B B, et al. Numerical investigation of incompressible flow in grooved channels. Part 2:resonance and oscillatory heat transfer enhancement [J]. J. Fluid Mech.,1986,168:541-567.
[26]Nishimura T, Oka N, Yoshinaka Y, et al. Influence of imposed oscillatory frequency on mass transfer enhancement of grooved channels for pulsatile flow[J], Int. J. Heat Mass Transfer,2000,43(13):2365-2374.
[27]Nishimura T, Kojima N. Mass transfer enhancement in a symmetric sinusoidal wavy-walled channel for pulsatile flow [J]. Int J Heat Mass Transfer,1995,38(10):1719-1731.
[28]Nishimura T, Matsune S. Vortices and wall shear stresses in asymmetric and symmetric channels with sinusoidal wavy walls for pulsatile flow at low reynolds Numbers [J]. Int. J. Heat Fluid Flow,1998,19:583-593.
[29]Nishimura T, Bian Y N., Kunitsugu K. Mass-transfer enhancement in a wavy-walled tube by imposed fluid oscillation[J]. AIChE Journal,2004,50(4):762-770.
[30]Mackley M R, Tweddle G M, W yatt ID. Experimental heat transfer measurement s for pulsatile flow in baffled tubes[J]. Chem S ci E ng,1990,45(5):1237 1242.
[31]俞接成,李志信.环形内肋片圆管层流脉冲流动强化对流换热数值分析[J].清华大学学报(自然科学版),2005,45(8)：1091-1094.
[32]杨卫卫,何雅玲,陶文铨,赵春凤.凹槽通道中脉动流动强化传质的数值研究[J].西安交通大学学报,2004,38(11)：1119-1122.
[33]何雅玲,杨卫卫,赵春凤,陶文铨.脉动流动强化换热的数值研究[J].工程热物理学报,2005,26(3)：495-497.
[34]贾宝菊,孙发明,卞永宁,徐新生.波壁管内的脉动流动及传质强化的数值模拟[J].化工学报,2009,60(1)：6-14.
[35]Bian Y, Jia B.Mass transfer characteristics in an axisymmetric wavy-walled tube for pulsatile flow with backward flow[J].Heat Mass Transfer,2009,45:693-702.
[36]谢公南,王秋旺,曾敏,罗来勤.渐扩渐缩波纹通道内脉动流的传热强化[J].高校化学工程学报,2006,20(1)：31-35.
[37]谢公南,王秋旺,曾敏,罗来勤.脉动参数对波纹通道内传热强化的影响[J].计算物理,2006,23(6)：673-678.
[38]郑军,曾丹苓,王萍,高虹.利用流体脉动强化换热的实验研究[J].热科学与技术,2003,9：245-249.
[39]胡玉生,曾丹苓,李友荣,吴双应.恒壁温下管内流体脉动对流换热的数值模拟[J].工业加热,2006,35：3-6.
[40]Greiner M, Fischer P F, Tufo H. Numerical simulations of resonant heat transfer augmentation at low reynolds numbers[J]. J. Heat Transfer,2002,124:1169-1175
[41]Mackley M. R., Stonestreet P. Heat transfer and associated energy dissipation for oscillatory flow in baffled tubes[J]. Chem. Eng. Sci.,1995,50:2211-2224.
[42]刘政崇.高低速风洞气动与结构设计[M].北京：国防工业出版社,2003.
[43]杨小弟.分析化学技能训练[M].北京：化学工业出版社,2008.
[44]Cloeman H W, J. W. G. Steele, Experimentation and Uncertainty Analysis for Engineers[M], John Wiley & Sons, Inc 1989.
[2]王补宣.工程传热学[M].北京：科学出版社,1998.
[3]崔海亭,彭培英.强化传热新技术及其应用[M].北京：化学工业出版社,2006.
[4]阎浩峰,甘永平.新型换热器与传热强化[M].北京：宇航出版社,1991.
[5]朱聘冠.换热器原理与计算[M].北京：清华大学出版社,1987.
[6]秦叔经,叶文邦.换热器[M].北京：化学工业出版社,2003.
[7]朱冬生,钱颂文.强化传热技术及其设计应用[J].化工装备技术,2000,6：3-11.
[8]Wickramasinghe S R, Han B, Garcia J D, et al. Microporous membrane blood oxygenators[J].AIChE Journal,2005,51 (2):656-670.
[9]Beskok, Warburton T C. Arbitrary Lagrangian Eulerian Analysis of a Bidirectional Micro-Pump Using Spectral Elements [J]. Int. J. Comput. Eng. Sci.2001,2(1):43-57.
[10]Yi M, Bau H H, Hu H. A Peristaltic Meso-Scale Mixer[C]. ASME-IMECE.2000, MEMS 2, Orlando, FL,2000,367-374.
[11]Sert C, Beskok A. Oscillatory Flow Forced Convection in Micro Heat Spreaders [J]. Numer. Heat Transfer, Part A,2002,42 (7):685-705.
[12]Kim S Y, Kang B H, Hyun J M. Forced convection heat transfer from two heated blocks in pulsating channel flow[J]. Int. J. Heat Mass Transfer,1998,41:625-634.
[13]Bergles A E. The influence of flow vibrations on forced-convection heat transfer[J]. J. Heat Transfer,1964,7(1):102-106.
[14]Bergles A E, Newell P H. The influence of ultrasonic vibrations on heattransfer to waterflowing in annuli[J]. Int. J. Heat Transfer,1965,8:1273-1280.
[15]Jackon T W, Purdy K R. Resonant pulsating flow and convective heat transfer[J]. J. Heat Transfer,1965,87 (4):507-512.
[16]Nishimura T, Oka N, Yoshinaka Y, et al. Influence of imposed oscillatory frequency on mass transfer enhancement of grooved channels for pulsatile flow[J]. Int. J. Heat Mass Transfer,2000,43(13):2365-2374.
[17]Kunitsugu K, Nishimura T, Tanoue K. Mass transfer enhancement by pulsatile flows in grooved channels (The effects of groove length on the resonant mass transfer enhancement) [J]. Heat Transfer—Asian research,2008,37 (4):240-257.
[18]Greiner M. An experimental investigation of resonant heat transfer heat transfer enhancement in grooved channels [J]. Int. J. Heat Mass Transfer,1991,34:1383-1391.
[19]Yu J C., Li Z X., Zhao T S. An analytical study of pulsating laminar heat convection in a circular tube with constant heat flux[J]. Int. J. Heat Mass Transfer,2004, 47:5297-5301.
[20]Jin D X, Lee Y P, Lee D Y. Effects of the pulsating flow agitation on the heat transfer in a triangular grooved channel[J]. Int. J. Heat Mass Transfer,2007,50:3062-3071.
[21]Nishamura T, Ohori Y. Flow chatacteristics in a channel with symmetric wavy wall for steay flow[J]. J. Chem. Eng. Japan,1984, 17:466-471.
[22]Nishimura T, Kojima N. Mass transfer enhancement in a symmetric sinusoidal wavy-walled channel for pulsatile flow[J]. Int J Heat Mass Transfer,1995,38(10):1719-1731.
[23]Habib M A,Attya A M. Convective heat transfer characteristics of laminar pulsating pipe air flow[J].Heat and Mass Transfer,2002,38:221-232.
[24]Ghaddar N K, K Z Korczak, Mikic B B, et al. Numerical investigation of incompressible flow in grooved channels. Part 1:Stability and self-sustained oscillations[J]. J. Fluid Mech.,1986,163:99-127.
[25]Ghaddar N K, Magen M, Mikic B B, et al. Numerical investigation of incompressible flow in grooved channels. Part 2:resonance and oscillatory heat transfer enhancement [J]. J. Fluid Mech.,1986,168:541-567.
[26]Nishimura T, Oka N, Yoshinaka Y, et al. Influence of imposed oscillatory frequency on mass transfer enhancement of grooved channels for pulsatile flow[J], Int. J. Heat Mass Transfer,2000,43(13):2365-2374.
[27]Nishimura T, Kojima N. Mass transfer enhancement in a symmetric sinusoidal wavy-walled channel for pulsatile flow [J]. Int J Heat Mass Transfer,1995,38(10):1719-1731.
[28]Nishimura T, Matsune S. Vortices and wall shear stresses in asymmetric and symmetric channels with sinusoidal wavy walls for pulsatile flow at low reynolds Numbers [J]. Int. J. Heat Fluid Flow,1998,19:583-593.
[29]Nishimura T, Bian Y N., Kunitsugu K. Mass-transfer enhancement in a wavy-walled tube by imposed fluid oscillation[J]. AIChE Journal,2004,50(4):762-770.
[30]Mackley M R, Tweddle G M, W yatt ID. Experimental heat transfer measurement s for pulsatile flow in baffled tubes[J]. Chem S ci E ng,1990,45(5):1237 1242.
[31]俞接成,李志信.环形内肋片圆管层流脉冲流动强化对流换热数值分析[J].清华大学学报(自然科学版),2005,45(8)：1091-1094.
[32]杨卫卫,何雅玲,陶文铨,赵春凤.凹槽通道中脉动流动强化传质的数值研究[J].西安交通大学学报,2004,38(11)：1119-1122.
[33]何雅玲,杨卫卫,赵春凤,陶文铨.脉动流动强化换热的数值研究[J].工程热物理学报,2005,26(3)：495-497.
[34]贾宝菊,孙发明,卞永宁,徐新生.波壁管内的脉动流动及传质强化的数值模拟[J].化工学报,2009,60(1)：6-14.
[35]Bian Y, Jia B.Mass transfer characteristics in an axisymmetric wavy-walled tube for pulsatile flow with backward flow[J].Heat Mass Transfer,2009,45:693-702.
[36]谢公南,王秋旺,曾敏,罗来勤.渐扩渐缩波纹通道内脉动流的传热强化[J].高校化学工程学报,2006,20(1)：31-35.
[37]谢公南,王秋旺,曾敏,罗来勤.脉动参数对波纹通道内传热强化的影响[J].计算物理,2006,23(6)：673-678.
[38]郑军,曾丹苓,王萍,高虹.利用流体脉动强化换热的实验研究[J].热科学与技术,2003,9：245-249.
[39]胡玉生,曾丹苓,李友荣,吴双应.恒壁温下管内流体脉动对流换热的数值模拟[J].工业加热,2006,35：3-6.
[40]Greiner M, Fischer P F, Tufo H. Numerical simulations of resonant heat transfer augmentation at low reynolds numbers[J]. J. Heat Transfer,2002,124:1169-1175
[41]Mackley M. R., Stonestreet P. Heat transfer and associated energy dissipation for oscillatory flow in baffled tubes[J]. Chem. Eng. Sci.,1995,50:2211-2224.
[42]刘政崇.高低速风洞气动与结构设计[M].北京：国防工业出版社,2003.
[43]杨小弟.分析化学技能训练[M].北京：化学工业出版社,2008.
[44]Cloeman H W, J. W. G. Steele, Experimentation and Uncertainty Analysis for Engineers[M], John Wiley & Sons, Inc 1989.