Determination of optimum parameters using different nano fluids in heat pipe heat exchangers with response surface method

Abstract

In this study, optimum parameters affecting the thermal efficiency of heat pipes were determined experimentally with response surface method using different types of nanofluids in heat exchangers. Experimental design was carried out at three levels for four parameters affecting thermal efficiency. Experiments were made for Al2O3, TiO2 and SiO2 at 0.2-0.4-0.6% concentrations. Nanofluid suspensions were formed using isopropyl alcohol as the base fluid. The inlet temperatures in the evaporator region were determined as 30-60-90 °C, and the Reynolds numbers in the condenser region were determined as 7200, 14400 and 21600. The thermal efficiencies of the heat pipes were calculated as a result of the experiments carried out in accordance with the experimental design created with the response surface method. The accuracy of the model was tested with analysis of variance (ANOVA) and optimum parameters were obtained as nanoparticle SiO2, concentration 0.32%, evaporator inlet temperature 90 °C and Reynolds number 21600 in the condenser.