Ali Akbar Golneshan - Associate Professor of mechanical engineering, Department of mechanical engineering, Shiraz University, Shiraz, Iran
Ario Madani - Master of science in mechanical engine, Department of mechanical engineering, Shiraz University, Shiraz, Iran

The turbulent flow and heat transfer characteristics for annuli with longitudinal internal fins were analyzed via RNG κ-ε model. Application was made to air flows with variable properties depending on temperature for three Reynolds numbers. Not only the variation of parameters such as temperature, velocity and pressure are reported but also the skin friction coefficient, friction factor, Nu number and heat exchanger effectiveness is calculated. All fluid properties are considered temperature variable and the solution domain includes both the body and the fluid. Boundary conditions are variable wall temperature at the outer wall and isolated at the inner wall.

Annular - Turbulent – Heat transfer - Finned