新型仿生结构强化管流动与换热性能数值研究
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摘要
本文以仿生结构强化管为研究对象,模拟研究了不同相对深度h/D和排列密度d~2/pl下的管内湍流的流动和换热性能,并与丁胞管进行了对比。结果表明,仿生强化管能够显著增加凸起附近流体径向分速度,增加流体的扰动,有效地增加了冷热流体的混合;在Re为1×10~4～4×10~4的变化范围内,换热增强因子Nu/Nu_0、阻力增强因子f/f_0及综合评价因子(Nu/Nu_0)/(f/f_0)的变化范围分别是1.11～2.13、1.49～3.72和0.45～1.13;低流速下,在传热综合性能评价图上位于4区,表明强化管具有良好的综合换热性能。最后,本文以无量纲参数相对深度h/D、排列密度d~2/pl以及雷诺数Re为变量总结出Nu数和阻力系数f的经验关联式,误差在10%以内。上述研究结果表明,仿生结构管在湍流情况下,具有良好的综合换热性能。
The turbulent flow and heat transfer performance of the biomimetic tube was numerically investigated with the non-dimensional parameters(relative depth h/D and arranging density d~2/pl)varied. Compared with dimpled tubes, the simulation results showed that the protrusion of the biomimetic tube increased the velocity magnitude in diameter direction and intensified the mixing of the fluids, which led to a better heat transfer performance. In the range of 1×10~4～4×10~4 for Re,the Nu for the enhanced tube was 11%～113% higher than that for smooth tube, while the friction factors was increased by 49%～272%. As a result, the performance evaluation factor of the biomimetic tube ranged from 0.45 to 1.13. At low flow rate, the working points are located in the region 4, which indicates an excellent heat transfer performance. Further, the empirical formulas for Nu and fwere respectively fitted in terms of the non-dimensional parameters(relative depth h/D, arranging density d~2/pl and Reynold number Re) with the errors within 10%. It was observed that the biomimetic tube could achieve profound heat transfer enhancement with acceptable pressure loss penalty.
The turbulent flow and heat transfer performance of the biomimetic tube was numerically investigated with the non-dimensional parameters(relative depth h/D and arranging density d~2/pl)varied. Compared with dimpled tubes, the simulation results showed that the protrusion of the biomimetic tube increased the velocity magnitude in diameter direction and intensified the mixing of the fluids, which led to a better heat transfer performance. In the range of 1×10~4～4×10~4 for Re,the Nu for the enhanced tube was 11%～113% higher than that for smooth tube, while the friction factors was increased by 49%～272%. As a result, the performance evaluation factor of the biomimetic tube ranged from 0.45 to 1.13. At low flow rate, the working points are located in the region 4, which indicates an excellent heat transfer performance. Further, the empirical formulas for Nu and fwere respectively fitted in terms of the non-dimensional parameters(relative depth h/D, arranging density d~2/pl and Reynold number Re) with the errors within 10%. It was observed that the biomimetic tube could achieve profound heat transfer enhancement with acceptable pressure loss penalty.
引文
[1] He Ya-Ling, Tao Wen-Quan. Convective Heat Transfer Enhancement:Mechanism, Techniques and Performance Evaluation[J]. Advances in Heat Transfer, 2014, 46:87-186
[2]何雅玲,陶文铨.强化单相对流换热的基本机制[J].机械工程学报,2009,45(3):27-38HE Ya-Ling, TAO Wenquan. Fundamental Mechanism of Enhancing Single-phase Convective Heat Transfer[J].Journal of Mechanical Engineering, 2009, 45(11):27-38
[3]何雅玲,雷勇刚,田丽亭,等.高效低阻强化换热技术的三场协同性探讨[J].工程热物理学报,2009, 30(11), 1903-1905HE Ya-Ling, LEI Yonggang, TIAN Liting, et al. An Analysis of Three-field Synergy on Heat Transfer Augmentation With Low Penalty of Pressure Drop[J]. Journal of Engineering Thermophysics, 2009, 30(11):1903-1905
[4] Tao Wen-Quan, He Ya-Ling, Wang Qiu-Wang, et al. A Unified Analysis on Enhancing Single Phase Convective Heat Transfer with Field Synergy Principle[J]. International Journal of Heat&Mass Transfer, 2002, 45(24):4871-4879
[5] He Ya-Ling, Zhang Yu-Wen. Advances and Outlooks of Heat Transfer Enhancement by Longitudinal Vortex Generators[J]. Advances in Heat Transfer, 2012, 44:119-185
[6]何雅玲,楚攀,谢涛.纵向涡发生器在管翅式换热器中的应用及优化[J].化工学报,2012, 63(3):746-759HE Ya-Ling, CHU Pan, XIE Tao. Application and Optimization of Fin-and-tube Heat Exchangers with Longitudinal Vortex Generators[J]. CIESE Journal, 2012, 63(3):746-759
[7] Huisseune H,T'Joen C, Jaeger P D, et al. Performance Enhancement of a Louvered fin Heat Exchanger by Using Delta Winglet Vortex Generators[J]. International Journal of Heat&Mass Transfer, 2013, 56(1/2):475-487
[8]李瑞,何雅玲,楚攀,等.丁胞型强化换热管的数值模拟[J].工程热物理学报,2008, 29(11):1947-1949LI Rui, HE Ya-ling, Chu Pan et al. Numerical Simulation of Dimpled Tubes for Heat Transfer Enhancement[J]. Journal of Engineering Thermophysics, 2008, 29(11):1947-1949
[9] Won S Y, Ligrani P M. Flow Characteristics Along and Above Dimpled Surfaces with Three Different Dimple Depths Within a Channel[J]. Journal of Mechanical Science&Technology, 2007, 21(11):1901
[10] Wang Yu, He Ya-Ling, Lei Yong-Gang, et al. Heat Transfer and Hydrodynamics Analysis of a Novel Dimpled Tube[J]. Experimental Thermal&Fluid Science, 2010, 34(8):1273-1281
[11] Chang S W, Chiang K F, Chou T C. Heat Transfer and Pressure Drop in Hexagonal Ducts With Surface Dimples[J]. Experimental Thermal&Fluid Science, 2010, 34(8):1172-1181
[12]唐新宜.矩形通道内流动与强化传热的实验与数值研究[D].广州:华南理工大学,2012TANG Xin-Yi. Experimental and Numerical Investiga-tion of Hydrodynamics and Heat Transfer in Rectangular Channel[D]. Guangzhou:South China University of Technology, 2012
[13]杨世铭,陶文铨.传热学[M].第四版.高等教育出版社,2006
[14] Kuwahara H, Takahashi K, Yanagida T, et al. 4794775Method of Producing a Heat Transfer Tube for SinglePhase Flow[J]. Heat Recovery Systems&CHP, 1990,10(1):i-i
[15] Xiong R, Chung J N. A New Model for Three-dimensional Random Roughness Effect on Friction Factor and Heat Transfer in Microtubes[J]. International Journal of Heat&Mass Transfer, 2010, 53(15):3284-3291
[16] Rabas T J, Webb R L, Thors P, et al. Influence of Roughness Shape and Spacing on the Performance of ThreeDimensional Helically Dimpled Tubes[J]. Journal of Enhanced Heat Transfer, 1993, 1(1):53-64
[2]何雅玲,陶文铨.强化单相对流换热的基本机制[J].机械工程学报,2009,45(3):27-38HE Ya-Ling, TAO Wenquan. Fundamental Mechanism of Enhancing Single-phase Convective Heat Transfer[J].Journal of Mechanical Engineering, 2009, 45(11):27-38
[3]何雅玲,雷勇刚,田丽亭,等.高效低阻强化换热技术的三场协同性探讨[J].工程热物理学报,2009, 30(11), 1903-1905HE Ya-Ling, LEI Yonggang, TIAN Liting, et al. An Analysis of Three-field Synergy on Heat Transfer Augmentation With Low Penalty of Pressure Drop[J]. Journal of Engineering Thermophysics, 2009, 30(11):1903-1905
[4] Tao Wen-Quan, He Ya-Ling, Wang Qiu-Wang, et al. A Unified Analysis on Enhancing Single Phase Convective Heat Transfer with Field Synergy Principle[J]. International Journal of Heat&Mass Transfer, 2002, 45(24):4871-4879
[5] He Ya-Ling, Zhang Yu-Wen. Advances and Outlooks of Heat Transfer Enhancement by Longitudinal Vortex Generators[J]. Advances in Heat Transfer, 2012, 44:119-185
[6]何雅玲,楚攀,谢涛.纵向涡发生器在管翅式换热器中的应用及优化[J].化工学报,2012, 63(3):746-759HE Ya-Ling, CHU Pan, XIE Tao. Application and Optimization of Fin-and-tube Heat Exchangers with Longitudinal Vortex Generators[J]. CIESE Journal, 2012, 63(3):746-759
[7] Huisseune H,T'Joen C, Jaeger P D, et al. Performance Enhancement of a Louvered fin Heat Exchanger by Using Delta Winglet Vortex Generators[J]. International Journal of Heat&Mass Transfer, 2013, 56(1/2):475-487
[8]李瑞,何雅玲,楚攀,等.丁胞型强化换热管的数值模拟[J].工程热物理学报,2008, 29(11):1947-1949LI Rui, HE Ya-ling, Chu Pan et al. Numerical Simulation of Dimpled Tubes for Heat Transfer Enhancement[J]. Journal of Engineering Thermophysics, 2008, 29(11):1947-1949
[9] Won S Y, Ligrani P M. Flow Characteristics Along and Above Dimpled Surfaces with Three Different Dimple Depths Within a Channel[J]. Journal of Mechanical Science&Technology, 2007, 21(11):1901
[10] Wang Yu, He Ya-Ling, Lei Yong-Gang, et al. Heat Transfer and Hydrodynamics Analysis of a Novel Dimpled Tube[J]. Experimental Thermal&Fluid Science, 2010, 34(8):1273-1281
[11] Chang S W, Chiang K F, Chou T C. Heat Transfer and Pressure Drop in Hexagonal Ducts With Surface Dimples[J]. Experimental Thermal&Fluid Science, 2010, 34(8):1172-1181
[12]唐新宜.矩形通道内流动与强化传热的实验与数值研究[D].广州:华南理工大学,2012TANG Xin-Yi. Experimental and Numerical Investiga-tion of Hydrodynamics and Heat Transfer in Rectangular Channel[D]. Guangzhou:South China University of Technology, 2012
[13]杨世铭,陶文铨.传热学[M].第四版.高等教育出版社,2006
[14] Kuwahara H, Takahashi K, Yanagida T, et al. 4794775Method of Producing a Heat Transfer Tube for SinglePhase Flow[J]. Heat Recovery Systems&CHP, 1990,10(1):i-i
[15] Xiong R, Chung J N. A New Model for Three-dimensional Random Roughness Effect on Friction Factor and Heat Transfer in Microtubes[J]. International Journal of Heat&Mass Transfer, 2010, 53(15):3284-3291
[16] Rabas T J, Webb R L, Thors P, et al. Influence of Roughness Shape and Spacing on the Performance of ThreeDimensional Helically Dimpled Tubes[J]. Journal of Enhanced Heat Transfer, 1993, 1(1):53-64