Experimental Investigation on the Thermal Resistance of Straight Heat Pipes with Double-Ended Cooling and Middle-Heating at Different Tilt Angles

Document Type : Research Article

Authors

Department of Mechanical Engineering, University of Kashan, Kashan, Iran

Abstract

An experimental study has been investigated on the thermal resistance of straight heat pipes with double-ended cooling and middle heating at different tilt angles. Two cooling blocks installed on both ends of heat pipes and a coil heater placed in the middle as the condenser and evaporator sections respectively. The experiments were conducted at inclinations 0° to 90° for heat inputs 20 to 80 W. The effects of heat input variation, cooling water flow rate and tilt angle on the thermal resistance of heat pipes were studied. The obtained results compared with the conventional heat pipes. The results showed that by using the new cooling approach, the thermal resistance of the heat pipes can be reduced significantly. Also, in low heat inputs, increasing the cooling water flow rate increases the thermal performance of the heat pipes. The experimental results indicated that the tilt angle has a significant effect on the thermal resistance of the heat pipes. The minimum thermal resistance and the maximum effective thermal conductivity coefficient values are 0.2533 °C/W and 14072.65 W/m°C respectively, and they were observed at the tilt angle equal to 60° and for heat input of 60 W.

Keywords

Main Subjects

References

[1] L. Vasilev, P. Grakovich, D. Khrustalev, Limiting characteristic of inclined thermosyphon and heat pipes, Inzhenerno-Fizicheskii Zhurnal, 46 (1984) 709-716.
[2] Y. Kamotani, Performance of gravity-assisted heat pipes operated at small tilt angles, Heat transfer and thermal control systems,  (1978).
[3] R. Manimaran, K. Palaniradja, N. Alagumurthi, K. Velmurugan, An investigation of thermal performance of heat pipe using di-water, Science and Technology, 2(4) (2012) 77-80.
[4] Y.M. Hung, K.-K. Tio, Thermal analysis of optimally designed inclined micro heat pipes with axial solid wall conduction, International Communications in Heat and Mass Transfer, 39(8) (2012) 1146-1153.
[5] H. Tang, Y. Tang, B. Zhuang, G. Chen, S. Zhang, Experimental investigation of the thermal performance of heat pipes with double-ended heating and middle-cooling, Energy Conversion and Management, 148 (2017) 1332-1345.
[6] T. Tharayil, L.G. Asirvatham, C.F.M. Cassie, S. Wongwises, Performance of cylindrical and flattened heat pipes at various inclinations including repeatability in anti-gravity–A comparative study, Applied Thermal Engineering, 122 (2017) 685-696.
[7] M. Hu, R. Zheng, G. Pei, Y. Wang, J. Li, J. Ji, Experimental study of the effect of inclination angle on the thermal performance of heat pipe photovoltaic/thermal (PV/T) systems with wickless heat pipe and wire-meshed heat pipe, Applied Thermal Engineering, 106 (2016) 651-660.
[8] A.A. Alammar, R.K. Al-Dadah, S.M. Mahmoud, Numerical investigation of effect of fill ratio and inclination angle on a thermosiphon heat pipe thermal performance, Applied Thermal Engineering, 108 (2016) 1055-1065.
[9] M. Mehrali, E. Sadeghinezhad, R. Azizian, A.R. Akhiani, S.T. Latibari, M. Mehrali, H.S.C. Metselaar, Effect of nitrogen-doped graphene nanofluid on the thermal performance of the grooved copper heat pipe, Energy Conversion and Management, 118 (2016) 459-473.
[10] W.I. Aly, M.A. Elbalshouny, H.A. El-Hameed, M. Fatouh, Thermal performance evaluation of a helically-micro-grooved heat pipe working with water and aqueous Al2O3 nanofluid at different inclination angle and filling ratio, Applied Thermal Engineering, 110 (2017) 1294-1304.
[11] E. Sadeghinezhad, M. Mehrali, M.A. Rosen, A.R. Akhiani, S.T. Latibari, M. Mehrali, H.S.C. Metselaar, Experimental investigation of the effect of graphene nanofluids on heat pipe thermal performance, Applied Thermal Engineering, 100 (2016) 775-787.
[12] Z. Xu, Y. Zhang, B. Li, C.-C. Wang, Y. Li, The influences of the inclination angle and evaporator wettability on the heat performance of a thermosyphon by simulation and experiment, International Journal of Heat and Mass Transfer, 116 (2018) 675-684.
[13] M. Mahdavi, S. Tiari, S. De Schampheleire, S. Qiu, Experimental study of the thermal characteristics of a heat pipe, Experimental Thermal and Fluid Science, 93 (2018) 292-304.
[14] A.A. Abdulshaheed, P. Wang, G. Huang, C. Li, High performance copper-water heat pipes with nanoengineered evaporator sections, International Journal of Heat and Mass Transfer, 133 (2019) 474-486.
[15] G. Kumaresan, S. Venkatachalapathy, L.G. Asirvatham, Experimental investigation on enhancement in thermal characteristics of sintered wick heat pipe using CuO nanofluids, International Journal of Heat and Mass Transfer, 72 (2014) 507-516.
[16] T. Yousefi, S. Mousavi, B. Farahbakhsh, M. Saghir, Experimental investigation on the performance of CPU coolers: Effect of heat pipe inclination angle and the use of nanofluids, Microelectronics Reliability, 53(12) (2013) 1954-1961.
[17] H. Tang, Y. Tang, J. Li, Y. Sun, G. Liang, R. Peng, Experimental investigation of the thermal performance of heat pipe with multi-heat source and double-end cooling, Applied Thermal Engineering, 131 (2018) 159-166.
 
Amirkabir Journal of Mechanical Engineering
Volume 53, Issue 1
April 2021
Pages 279-302

Files

Share

How to cite

Statistics