- Gazi University Journal of Science
- Vol: 31 Issue: 2
- Experimental Investigation of an Al2O3 / Distilled Water Nanofluid Used In the Heat Pipes of Heat Ex...
Experimental Investigation of an Al2O3 / Distilled Water Nanofluid Used In the Heat Pipes of Heat Exchangers
Authors : Ahmet ÖZTÜRK, Mehmet ÖZALP, Adnan SÖZEN
Pages : 616-626
View : 11 | Download : 2
Publication Date : 2018-06-01
Article Type : Research
Abstract :This study investigates the thermal performance of a heat pipe heat recovery system in air-to-air heat recovery systems using a nanofluid of Al 2 O 3 (aluminum oxide) particles and distilled water. The experimental setup used 15 wickless vacuumed copper pipes with a length of 1000 mm, a 10.5 mm inner diameter and a 12 mm outer diameter. The evaporator section consists of 450 mm of heat pipes, the condenser section is 400 mm, and the adiabatic section is 150 mm. In experimental studies, 33% of the evaporator volume of the heat pipes was filled with working fluids. Experiments were carried out at temperatures between 25 º C and 90 º C by using five different cooling air flows (40 g/s, 42 g/s, 45 g/s, 61 g/s and 84 g/s), and two different heating powers (3 kW and 6 kW) for the evaporation section, to determine the heat removed from the condensation section. Experiments were performed for distilled water and Al 2 O 3 nanofluid, respectively, and the results were compared with each other. As a result of the experiments, it was observed that using a nanofluid as the working fluid increased the efficiency of the heat pipe. The highest efficiency ( η = 59%) was obtained in the experiments carried out using an Al 2 O 3 nanofluid at a heating power of 3 kW and an air flow of 112 g/s.Keywords : Aluminum oxide, heat pipe, heat recovery, nanofluid