FIRST NUMERICAL RESULTS ON FORCED-CONVECTION HEAT TRANSFER INSIDE A RECTANGULAR CHANNEL WITH STRAIGHT RIBS ON LOWER AND UPPER WALLS

This paper presents the first results of a numerical investigation on the fluid dynamics and heat transfer characteristics of a forced air-flow inside a rectangular channel with straight ribs on the lower and upper walls. The Reynolds number is 4180. The upper and lower walls are maintained at constant temperature whereas the side walls are adiabatic. The duct is 120 mm wide, 12 mm height and 840 mm long. The ribs have a square cross section of 4 mm2 and are 20 mm spaced. The calculations are carried out with a commercial code using a RANS approach with different turbulence models. A two-dimensional numerical analysis is performed on the entire fluid domain. The average heat transfer coefficient over the entire channel and the pressure drops are compared with the measured values from an experimental facility with the same geometry and operating conditions as the numerical model.