Effects of Surface Modifications on Heat and Fluid Flow Characteristics in Fluid Jets Impinging on a Heated Surface

Impinging jets are well known for their high heat transfer rates. This paper investigates a novel technique for further enhancing heat transfer from an impinging fluid jet. The proposal introduces modifications to the surface in the form of cylindrical cavities (or 'micro-cups') directly beneath the jet. A single impinging jet impinging into a micro-cup with a diameter of twice that of the jet is numerically simulated. A range of jet-to-surface distances, micro-cup depths and jet velocities are modelled. Effects on the heat transfer are identified and discussed. Results indicate heat transfer enhancement is achieved for a number of the studied geometries, with the 'net-depth' a significant factor affecting the heat transfer.