Heat transfer intensification by jet impingement – numerical analysis using RANS approach

Abstract

Jet impingement is a method of the heat transfer enhancement applied in the engineering systems. The idea is to generate fast-flow fluid jet which impinge on the heated (or cooled) surface, causing significantly higher heat transfer rate. Although some flat surface jet impingement cases are described in the literature, the validated data is still limited. The reason is coming from the fact, that these flows are hydrodynamically complex. Therefore the numerical analysis is necessary to understand the phenomena, especially in the range of turbulent flow. The well-known and accurate method is Reynolds Averaged Navier-Stokes (RANS) approach. However, depending on the applied turbulence model, various results can be obtained. The reason is that the jet impingement strongly depends on the complex boundary layer effects and their resolving is still challenging for RANS models and until now it is their weakest point. In the paper, the hydrodynamic and thermal, numerical results of jet impingement are presented, depending on selected RANS based models. The aim was to indicate their ability to anticipate the turbulence parameters.

Curved Surface Minijet Impingement Phenomena Analysed with ζ-f Turbulence Model

“…The values were obtained at the first mesh nodes near the heat transferring wall. The reason for choosing these particular values was shown in the authors' publication [49]. As Nusselt number distribution is influenced mostly by the phenomena in the near-wall region, it should be referred to corresponding values of other variables from this zone, despite the fact, that for example global maxima of turbulence kinetic energy appear significantly above that region.…”