[01] Raad Muzahem Fenjan, Materials Engineering Department, College of Engineering, Al-Mustansiriyah University, Baghdad, Iraq.

This work studies the hydrodynamic characteristics and heat transfer for both oil Newtonian and non-Newtonian fluids. Therefore the comparison between velocity and temperature distribution Profiles, pressure drop and Nusselt numbers for heating and cooling of these fluid were achieved. The fluids flow into tubes with laminar flow condition. The search leads to shown the effects of rheological properties of non-Newtonian fluids and their variation with temperature. For the theoretical work, the fluid flow through circular tube was taken under the conditions of constant wall temperature, fully developed flow and a uniform temperature with neglecting axial conduction heat transfer axial conduction heat transfer. Temperature-dependent power law relationship used to describe the rheological properties. It was found that the hydrodynamic characteristics and pressure drop were affected by the fluid temperature. For the experimental work, the Newtonian fluid is oil with specific heat of (2 KJ/Kg °C at 50°C), thermal conductivity of (0.14 W/m °C at 50°C) and non-Newtonian fluid is carbopol polymer with (2.8 KJ/Kg °C at 20°C) and thermal conductivity of (0.3 W/m °C at 20°C). Tests covered a range of Graetz numbers (Gz) from (160 to 1600) also the temperature differences from (50°C to 90°C) for heating and (70°C to 30°C) for cooling.

Newtonian Fluid, Non-newtonian Fluid, Fluid Velocity Profile, Fluid Temperature Profile

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