EFFECT OF (MGO) NANOFLUID ON HEAT TRANSFER CHARACTERISTICS FOR INTEGRAL FINNED TUBE HEAT EXCHANGER

Experimental investigations have been carried out in this paper to study the enhancement of heat transfer characteristics for cross flow low integral finned tube heat exchanger with using of (MgO) nanofluid. The study includes designing and manufacturing of test section from Pyrex glass with dimensions (250?500?1200) mm width, height and length, respectively. has a single copper tube with eight passes.. The low integral finned tube with (19 mm) inner diameter, (21 mm) root diameter and (24 mm) outer diameter. The fin height is (1.5 mm), thickness (1 mm) and the pitch is (2 mm). Air was used as a cooling fluid passing across the test tube with a range of velocities (1, 2, 3 and 4) m/sec. The inner side flow rates with a range of (2, 3, 4, 5 and 6) L/min. for water and for nanofluid. The fluid temperatures at the inlet of test tube were (50, 60, 70, 80) °C. Magnesium Oxide (MgO) nanoparticle powder with (40 nm) diameter was dispersed in distilled water with different volume concentrations (0.15, 0.35, 0.55, and 0.75) % by volume is used to prepare the nanofluid. The results showed increasing of thermal conductivity and density of fluid when using nanofluid, the results also showed enhancement of heat transfer characteristics when using the nanofluid.