Obtaining uniform cooling on a hot surface by a novel swinging slot impinging jet

•Obtaining higher uniform Nusselt distributions on a constantly heated surface.•The ability to reach uniform cooling by applying a single jet.•Attaining uniform cooling with relatively lower nozzle to target surface ratio.•Approaching more uniform cooling by applying higher maximum of swinging angle.•Observation of an extremum in Nusselt number by varying the frequency. In this study, a novel 2D laminar Swinging Slot Impinging Jet (SSIJ) on a heated flat surface was investigated using numerical simulation. The impinging jet was introduced to improve the uniform cooling of a hot surface while enhancing the heat transfer rate by disrupting the boundary layer. The impinging jet moves along the target surface similar to the swinging motion of a pendulum. The effects of Reynolds number, dimensionless jet to target distance, maximum angle of swinging, and frequency of jet oscillations were studied, and physics of the new impinging jet were fully discussed. Lastly, optimization was undertaken to search for the optimal variables leading to uniform heat fluxes. A combination of pattern search and gradient-based methods was used to minimize the root mean square of the difference between the local Nusseltnumber and a target uniform Nusselt distribution. To achieve uniform cooling, 15 cases were investigated (5 Nusselt numbers and 3 nozzle to target surface ratios). It was found that for the nozzle to target surface ratios of 0.5 and 0.35, SSIJ was remarkably successful to accomplish uniform cooling for all Nusselt numbers.