Thermal characteristics of grooved heat pipe with hybrid nanofluids

Abstract

In the present study, the specially designed grooved heat pipe charged with nanofluids was investigated in terms of various parameters such as heat transfer rate (50-300 W with 50 W interval), volume concentration (0.005%, 0.05%, 0.1%, and hybrid combinations), inclination (5°, 45°, 90°), cooling water tem-perature (1 °C, 10 °C, 20 °C), surface state, transient state and so on. Hybrid nanofluids with different volume concentration ratios with Ag-H2O and Al2O3-H2O were used as working fluids on a grooved heat pipe. Comparing with the pure water system, nanofluidic and hybrid nanofluidic systems shows greater overall thermal resistance with increasing nano-particle concentration. Also hybrid nanofluids make the system deteriorate in terms of thermal resistance. The post nanofluid experimental data regarding grooved heat pipe show that the heat transfer performance is similar to the results of nanofluid system. The thermal performance of a grooved heat pipe with nanofluids and hybrid nanofluids were varied with driving parameters but they led to worse system performance.