Unsteady RANS simulation of fluid dynamic and heat transfer in an oblique self-oscillating fluidic oscillator array. (October 2021) - Ming, Tingzhen
Highlights: A microchannel heat exchanger made by the fluidic oscillators array was designed. The oscillation modes of two parallel fluidic oscillators were studied. The time-resolved pressure field and velocity field were analyzed. The heat transfer performance of the fluidic oscillators array was evaluated. Abstract: Impinging jet played an important role in cooling technology. The steady-state jet could be transformed into an oscillatory one based on the intrinsic flow instability mechanisms by using self-oscillating fluidic oscillators. In this paper, a high-performance microchannel heat exchanger based on a fluidic oscillator array was presented. The fluidic oscillators were tilted at an angle of 30° above the impinging surface to extend the influence area of the jets. The unsteady RANS turbulence models were adopted to study the fluid dynamic and heat transfer performance of the jet array. The time-resolved pressure field and velocity field were calculated to show that the parallel oscillators would produce three modes, including co-directional oscillation, reverse oscillation, and irregular oscillation, under synchronous and asynchronous output phases. The sweeping jets improved the heat removal performance by increasing the average Nusselt number and enlarging the influence range on the external flow field. The heat removal performance of the sweeping jets was almost equivalent under different oscillation modes.