Numerical Analysis of Single Jet Impinging a Flat and Non-flat Plate

Abstract

The complexity of the flow field and heat transfer in jet impingement has led to several studies in order to increase the processes and products performance. Jet impingement is widely implemented, since it ensures high average heat transfer coefficients and the uniformity of the temperature over the target surface. However, the flow generated depends on several parameters related to the jet flow, such as jet velocity and temperature, and the target plate geometry. Complex impinging surfaces are identified in the majority of the applications, such as reflow soldering and cooling of turbines or solar systems. To increase the process efficiency, it is important to fully understand the interactions between the jet and the target surface. Considering the interest of this field, the present study is conducted to investigate the influence of the target surface on heat transfer in a single jet impingement process. To minimize the number of experiments, decreasing time and costs, the implementation of numerical tools is fundamental. In that sense, the impingement of the hot air jet over a flat and non-flat plate was predicted numerically using the ANSYS FLUENT software. The velocity and temperature profile were analyzed and the Nusselt number were compared for both cases. The results show the complexity of the flow generated in the vicinity of the step and the changes of the jet flow structure when it impinges a complex surface.