Experimental Investigation of an Al2O3 / Distilled Water Nanofluid Used In the Heat Pipes of Heat Exchangers

This study investigates the thermal performance of a heat pipe heat recovery system in air-to-airheat recovery systems using a nanofluid of Al2O3(aluminum oxide) particles and distilledwater. The experimental setup used 15 wickless vacuumed copper pipes with a length of1000 mm, a 10.5 mm inner diameter and a 12 mm outer diameter. The evaporator sectionconsists of 450 mm of heat pipes, the condenser section is 400 mm, and the adiabatic section is150 mm. In experimental studies, 33% of the evaporator volume of the heat pipes was filledwith working fluids. Experiments were carried out at temperatures between 25ºC and 90ºC byusing five different cooling air flows (40 g/s, 42 g/s, 45 g/s, 61 g/s and 84 g/s), and two differentheating powers (3 kW and 6 kW) for the evaporation section, to determine the heat removedfrom the condensation section. Experiments were performed for distilled water and Al2O3nanofluid, respectively, and the results were compared with each other. As a result of theexperiments, it was observed that using a nanofluid as the working fluid increased the efficiencyof the heat pipe. The highest efficiency (η = 59%) was obtained in the experiments carried outusing an Al2O3 nanofluid at a heating power of 3 kW and an air flow of 112 g/s.

PDF

___

Xuan, Y., Li, Q., “Heat transfer enhancement of nanofluids”, International Journal of Heat and Fluid Flow, 21(1): 58-64, (2000).
Sözen, A., Menlik, T., Gürü, M., Boran, K., Kılıç, F., Aktaş, M., Çakır, M. T., “A comparative investigation on the effect of fly-ash and alumina nanofluids on the thermal performance of twophase closed thermo-syphon heat pipes”, Applied Thermal Engineering, 96: 330-337, (2016).
Qu, J., Wu, H.-y., Cheng, P., “Thermal performance of an oscillating heat pipe with Al2O3–water nanofluids” International Communications in Heat and Mass Transfer, 37(2): 111-115, (2010).
Noie, S. H., Heris, S. Z., Kahani, M., Nowee, S. M., “Heat transfer enhancement using Al2O3/water nanofluid in a two-phase closed thermosyphon”, International Journal of Heat and Fluid Flow, 30(4): 700-705, (2009).
Hassan, M. I., Alzarooni, I. A., Shatilla, Y., “The Effect of Water-Based Nanofluid Incorporating Al2O3 Nanoparticles on Heat Pipe Performance”, Energy Procedia, 75: 3201-3206, (2015).
Vijayakumar, M., Navaneethakrishnan, P., Kumaresan, G., “Thermal characteristics studies on sintered wick heat pipe using CuO and Al2O3 nanofluids”, Experimental Thermal and Fluid Science, 79: 25-35, (2016).
Reji Kumar, R., Sridhar, K., Narasimha, M., “Heat Transfer Performance in Heat Pipe Using Al2O3 - DI Water Nanofluid”, International Journal of Material and Mechanical Engineering, 3(1): 1-5, (2014).
Hung, Y.-H., Teng, T.-P., Lin, B.-G., “Evaluation of the thermal performance of a heat pipe using alumina nanofluids”, Experimental Thermal and Fluid Science, 44: 504-511, (2013).
Hassan, H., Harmand, S., “Effect of using nanofluids on the performance of rotating heat pipe”, Applied Mathematical Modelling, 39(15): 4445-4462, (2015).
Teng, T.-P., Hsu, H.-G., Mo, H.-E., Chen, C.-C., “Thermal efficiency of heat pipe with alumina nanofluid”, Journal of Alloys and Compounds, 504, Supplement 1: 380-384, (2010).
Senthil, R., Ratchagaraja, D., Silambarasan, R., Manikandan, R., “Contemplation of thermal characteristics by filling ratio of Al2O3 nanofluid in wire mesh heat pipe”, Alexandria Engineering Journal, 55(2): 1063-1068, (2016).
Kim, H. J., Lee, S.-H., Kim, S. B., Jang, S. P., “The effect of nanoparticle shape on the thermal resistance of a flat-plate heat pipe using acetone-based Al2O3 nanofluids”, International Journal of Heat and Mass Transfer, 92: 572-577, (2016).
Zhang, J., Diao, Y. H., Zhao, Y. H., Tang, X., Yu, W. J., Wang, S., “Experimental study on the heat recovery characteristics of a new-type flat micro-heat pipe array heat exchanger using nanofluid”, Energy Conversion and Management, 75: 609-616, (2013).