enhancement of the thermal performance of a single turn pulsating heat pipe by adding micro-coppers into the base fluid

In this research, a series of experimental and numerical studies on the thermal performance of a single-turn pulsating heat pipe (php) using distilled water as base fluid and distilled water including micro-coppers were performed. thermal resistance, average temperatures of the hot region (evaporator), average temperatures of the cold part (condenser), and two-phase flow regime of the system were investigated at the different filling ratios, at input powers (20, 30, 40, 50 and 60w), at a concentration of micro-coppers (0.0625 g/ml). the oscillating heat pipe was fabricated with a copper capillary tube by choosing the internal and external diameters of 4 mm and 6 mm, respectively. experiments showed adding micro-coppers into base fluid improves the main mechanism of the php based on the oscillating motion of vapor plugs and liquid slugs. the lowest thermal resistance of the system at a filling ratio of 40%, at a concentration of micro-coppers (0.0625 g/ml), at heat input (60 w) was 0.95 deg c/w. meanwhile, cfd results illustrated adding micro-coppers into base fluid increases the turbulence intensity of the system especially in the evaporator up to 45% which enhances the heat transfer through the php in comparison to base fluid.