Heat transfer Augmentation in Double Pipe Heat Exchanger by Using (Al2O3) Nano-fluid

Abstract

In this study, the turbulent flow and heat transfer characteristics of Al2O3/Distilled water Nano-fluid with a range of the Reynolds number (Re = 6196.92–38669.54) and the range of volume concentrations (φ =0.5%, 1%, and 2%) are concentrated tentatively and numerically. The test rig includes cold liquid circle, hot liquid circle and the test portion, which is counter stream dual pipe heat exchanger with (2000) mm length. The chilly fluid (Distilled water) flowing through the external tube and the hot fluid (or Nano-liquid) move through the inner tube. The limit conditions of numerical (CFD) study is the same conditions as in experimental work additionally, thermally protected of the external wall. The hot Nano-liquid loop side with uniform speed at (0.176, 0.352, 0.529, 0.705, 0.881 and 1.058) m/s, and the cold distilled water circle with constant speed of (0.529) m/s. The outcomes were demonstrated that, the warmth transfer coefficient, (Nusselt numbers) expanded by expanding, Reynolds number, and the molecular concentration. The experimental and Numerical results indicate that the maximum enhancement in heat transfer coefficient (Nusselt number) were (48.93) % and (46.63) % separately, and the increasing in the friction factor was about (7.69) % as compared to the distilled water at the maximum discharging of (18) Liter/min and volume concentration of )2( %. Theoretical study included numerical analysis to solve governing differential equations in three dimensions through use of ready-program workbench ANSYS FLUENT bundle-(16) to study the effect of both Reynold number and focus on the amount of improvement in heat transfer and friction variable. The test results were demonstrated a decent concurrence with numerical results with the minimum and maximum difference were (5.75 and 11.41) percentage and the normal difference was (10.074) percentage was happening with Distilled-water.