| description abstract | This paper investigates numerically and experimentally the flow structure and convective heat transfers in an unconfined air gap of a discoid technology rotor–stator system. The cavity between the interdisk is defined by dimensionless spacing varying between G = 0.02 (Haidar et al., 2020, “Numerical and Experimental Study of Flow and Convective Heat Transfer on a Rotor of a Discoidal Machine With Eccentric Impinging Jet,” J. Therm. Sci. Eng. Appl., 12(2), 021012) and G = 0.16. For experimental data, an infrared thermography is applied to obtain a measurement of the rotor surface temperatures and a steady-state energy equation is solved to evaluate the local convective coefficients. A numerical study is performed with a computational code ansys-fluent and based to apply two different turbulence models named the Reynolds stress model (RSM) and k–ε renormalization group (RNG). The results of the numerical simulation are compared with experimental results on heat transfer for the rotational Reynolds number ranging from 2.38×105 to 5.44×105, the jet Reynolds numbers varying from 16.6×103 to 49.6×103, and for dimensionless spacing G between 0.04 and 0.16. Three heat transfer zones on the rotating disk surface are identified. A good accord between a numerical result and experimental data was obtained. Finally, a correlation relating the Nusselt number to the rotational Reynolds number, jet Reynolds number, and dimensionless spacing varying from 0.02 to 0.16 is proposed. | |
