JZUS - Journal of Zhejiang University SCIENCE

Journal of Zhejiang University SCIENCE A 2020 Vol.21 No.12 P.1008-1022

http://doi.org/10.1631/jzus.A2000057

Local heat transfer enhancement induced by a piezoelectric fan in a channel with axial flow

Author(s): Yun-long Qiu, Chang-ju Wu, Wei-fang Chen
Affiliation(s): School of Aeronautics and Astronautics, Zhejiang University, Hangzhou 310027, China
Corresponding email(s): wuchangju@zju.edu.cn
Key Words: Piezoelectric fan, Local heat transfer enhancement, Forced convection, Longitudinal vortex, Pressure drop

Share this article to： More <<< Previous Article \|

Abstract: The present work experimentally and numerically investigates the local heat transfer enhancement induced by a piezoelectric fan interacting with a cross flow in a local heated channel. The piezoelectric fan is placed along the flow direction and tested under different amplitudes and flow rates. In the simulations, a spring-based smoothing method and a local remeshing technique are used to handle the moving boundary problems. Hybrid mesh is used to reduce the size of dynamic mesh domain and to improve computational efficiency. The experimental and numerical values of the time-averaged mean Nusselt number are found to be in good agreement, with deviations of less than 10%. The experimental result shows that the heat transfer performance of the heated surfaces is substantially enhanced with a vibrating piezoelectric fan. The numerical result shows that the heat transfer enhancement comes from the strong longitudinal vortex pairs generated by the piezoelectric fan, which significantly promote heat exchange between the main flow and the near-wall flow. In the case of a=0.66 (a is the dimensionless amplitude) and Re=1820, the enhancement ratio of the time-averaged mean Nusselt number reaches 119.9%.

压电风扇对管内局部受迫对流换热的强化效果研究

目的:电子设备的局部过热问题对散热系统的设计提出了新的考验. 针对传统被动式散热技术调节困难、调节代价大等问题,本文提出使用压电风扇作为控制元件对管内局部过热区域进行主动对流换热效果强化的方案,期望通过实验与数值模拟研究掌握压电风扇在管内横流作用下的流动控制特性及强化传热机理,为压电风扇在实际工程中的应用提供理论指导.
创新点: 1. 通过基于等温设计的实验系统测试加热面在压电风扇作用下的时均努塞尔数,并证明压电风扇对管内局部区域对流换热效果的强化能力; 2. 通过数值模拟分析压电风扇的纵向涡产生特性并解释纵向涡对局部对流换热效果的强化机理.
方法:1. 利用铜热沉导热快、热容大等特性建立定常的等温换热面,并测量得到等温壁面在压电风扇作用下的时均努塞尔数; 2. 使用基于动网格技术的数值模拟,得到压电风扇作用下的流场与温度场信息,分析压电风扇的流动控制特性,并解释压电风扇强化局部对流换热的机理; 3. 通过参数化研究说明振幅和来流雷诺数对压电风扇强化对流换热效果的影响.
结论:1. 压电风扇的振动可以显著地强化管内局部区域的对流换热性能; 2. 压电风扇引起的对流换热强化主要来自其振动产生的纵向涡对; 3. 压电风扇的振动对管内流动压降的影响较小.
关键词：压电风扇;局部对流换热强化;受迫对流;纵向涡;压降

Reference

[1]Abdullah MK, Abdullah MZ, Ramana MV, et al., 2009. Numerical and experimental investigations on effect of fan height on the performance of piezoelectric fan in microelectronic cooling. International Communications in Heat and Mass Transfer, 36(1):51-58.

[2]Abdullah MK, Ismail NC, Abdullah MZ, et al., 2012a. Effects of tip gap and amplitude of piezoelectric fans on the performance of heat sinks in microelectronic cooling. Heat and Mass Transfer, 48(6):893-901.

[3]Abdullah MK, Ismail NC, Mujeebu MA, et al., 2012b. Optimum tip gap and orientation of multi-piezofan for heat transfer enhancement of finned heat sink in microelectronic cooling. International Journal of Heat and Mass Transfer, 55(21-22):5514-5525.

[4]Açikalin T, Wait SM, Garimella SV, et al., 2004. Experimental investigation of the thermal performance of piezoelectric fans. Heat Transfer Engineering, 25(1):4-14.

[5]Açikalin T, Garimella SV, Raman A, et al., 2007. Characterization and optimization of the thermal performance of miniature piezoelectric fans. International Journal of Heat and Fluid Flow, 28(4):806-820.

[6]Alsabery AI, Saleh H, Ghalambaz M, et al., 2019. Fluid-structure interaction analysis of transient convection heat transfer in a cavity containing inner solid cylinder and flexible right wall. International Journal of Numerical Methods for Heat & Fluid Flow, 29(10):3756-3780.

[7]Arshad A, Jabbal M, Yan YY, 2020. Synthetic jet actuators for heat transfer enhancement–a critical review. International Journal of Heat and Mass Transfer, 146:118815.

[8]Deng X, Luo ZB, Xia ZX, et al., 2019. Experimental investigation on the flow regime and impingement heat transfer of dual synthetic jet. International Journal of Thermal Sciences, 145:105864.

[9]Fairuz ZM, Sufian SF, Abdullah MZ, et al., 2014. Effect of piezoelectric fan mode shape on the heat transfer characteristics. International Communications in Heat and Mass Transfer, 52:140-151.

[10]Ghalambaz M, Jamesahar E, Ismael MA, et al., 2017. Fluid-structure interaction study of natural convection heat transfer over a flexible oscillating fin in a square cavity. International Journal of Thermal Sciences, 111:256-273.

[11]Ghalambaz M, Mehryan SAM, Izadpanahi E, et al., 2019a. MHD natural convection of Cu–Al₂O₃ water hybrid nanofluids in a cavity equally divided into two parts by a vertical flexible partition membrane. Journal of Thermal Analysis and Calorimetry, 138(2):1723-1743.

[12]Ghalambaz M, Chamkha AJ, Wen DS, 2019b. Natural convective flow and heat transfer of Nano-Encapsulated Phase Change Materials (NEPCMs) in a cavity. International Journal of Heat and Mass Transfer, 138:738-749.

[13]Ghalambaz M, Doostani A, Izadpanahi E, et al., 2020. Conjugate natural convection flow of Ag–MgO/water hybrid nanofluid in a square cavity. Journal of Thermal Analysis and Calorimetry, 139(3):2321-2336.

[14]Guo ZZ, He ZQ, Zhao WW, et al., 2018. Efficient mesh deformation and flowfield interpolation method for unstructured mesh. Acta Aeronautica et Astronautica Sinica, 39(12):126-137 (in Chinese).

[15]Hales A, Jiang X, 2018. A review of piezoelectric fans for low energy cooling of power electronics. Applied Energy, 215:321-337.

[16]Jamesahar E, Sabour M, Shahabadi M, et al., 2020. Mixed convection heat transfer by nanofluids in a cavity with two oscillating flexible fins: a fluid–structure interaction approach. Applied Mathematical Modelling, 82:72-90.

[17]Jeng TM, Liu CH, 2015. Moving-orientation and position effects of the piezoelectric fan on thermal characteristics of the heat sink partially filled in a channel with axial flow. International Journal of Heat and Mass Transfer, 85: 950-964.

[18]Jiang ZZ, Chen WF, Zhao WW, 2018. Numerical analysis of the micro-Couette flow using a non-Newton–Fourier model with enhanced wall boundary conditions. Microfluidics and Nanofluidics, 22(10), Article No. 10.

[19]Kimber M, Garimella SV, 2009. Cooling performance of arrays of vibrating cantilevers. Journal of Heat Transfer, 131(11):111401.

[20]Kurnia JC, Sasmito AP, Mujumdar AS, 2011. Evaluation of the heat transfer performance of helical coils of non-circular tubes. Journal of Zhejiang University-SCIENCE A (Applied Physics & Engineering), 12(1):63-70.

[21]Lee YJ, Singh PK, Lee PS, 2015. Fluid flow and heat transfer investigations on enhanced microchannel heat sink using oblique fins with parametric study. International Journal of Heat and Mass Transfer, 81:325-336.

[22]Li XJ, Zhang JZ, Tan XM, 2017. Convective heat transfer on a flat surface induced by a vertically-oriented piezoelectric fan in the presence of cross flow. Heat and Mass Transfer, 53(9):2745-2768.

[23]Li XJ, Zhang JZ, Tan XM, 2018a. Effects of piezoelectric fan on overall performance of air-based micro pin-fin heat sink. International Journal of Thermal Sciences, 126: 1-12.

[24]Li XJ, Zhang JZ, Tan XM, 2018b. An investigation on convective heat transfer performance around piezoelectric fan vibration envelope in a forced channel flow. International Journal of Heat and Mass Transfer, 126:48-65.

[25]Lin CN, 2013. Enhanced heat transfer performance of cylindrical surface by piezoelectric fan under forced convection conditions. International Journal of Heat and Mass Transfer, 60:296-308.

[26]Liu SF, Huang RT, Sheu WJ, et al., 2009. Heat transfer by a piezoelectric fan on a flat surface subject to the influence of horizontal/vertical arrangement. International Journal of Heat and Mass Transfer, 52(11-12):2565-2570.

[27]Ma HK, Su HC, Liu CL, et al., 2012. Investigation of a piezoelectric fan embedded in a heat sink. International Communications in Heat and Mass Transfer, 39(5):603-609.

[28]Mehryan SAM, Izadpanahi E, Ghalambaz M, et al., 2019. Mixed convection flow caused by an oscillating cylinder in a square cavity filled with Cu-Al₂O₃/water hybrid nanofluid. Journal of Thermal Analysis and Calorimetry, 137(3):965-982.

[29]Moffat RJ, 1988. Describing the uncertainties in experimental results. Experimental Thermal and Fluid Science, 1(1):3-17.

[30]Peles Y, Koşar A, Mishra C, et al., 2005. Forced convective heat transfer across a pin fin micro heat sink. International Journal of Heat and Mass Transfer, 48(17):3615-3627.

[31]Sufian SF, Abdullah MZ, Mohamed JJ, 2013. Effect of synchronized piezoelectric fans on microelectronic cooling performance. International Communications in Heat and Mass Transfer, 43:81-89.

[32]Wait SM, Basak S, Garimella SV, et al., 2007. Piezoelectric fans using higher flexural modes for electronics cooling applications. IEEE Transactions on Components and Packaging Technologies, 30(1):119-128.

[33]Wang XQ, Mujumdar AS, 2007. Heat transfer characteristics of nanofluids: a review. International Journal of Thermal Sciences, 46(1):1-19.

[34]Wen DS, Lin GP, Vafaei S, et al., 2009. Review of nanofluids for heat transfer applications. Particuology, 7(2):141-150.

[35]Xia CC, Chen WF, 2016. Boundary-layer transition prediction using a simplified correlation-based model. Chinese Journal of Aeronautics, 29(1):66-75.

[36]Xu Y, Moon C, Wang JJ, et al., 2019. An experimental study on the flow and heat transfer of an impinging synthetic jet. International Journal of Heat and Mass Transfer, 144: 118626.

[37]Yeom T, Simon TW, North M, et al., 2016. High-frequency translational agitation with micro pin-fin surfaces for enhancing heat transfer of forced convection. International Journal of Heat and Mass Transfer, 94:354-365.

Open peer comments: Debate/Discuss/Question/Opinion

<1>

Similar articles

- Go to

压电风扇对管内局部受迫对流换热的强化效果研究

Darkslateblue:Affiliate; Royal Blue:Author; Turquoise:Article

Reference