Abstract

Microjet impingement cooling devices promise high heat removal rates for the development of advanced thermal management solutions. However, understanding of microjet hydrodynamics is needed to optimize cooling performance. In this paper, we combined experiments and modeling to obtain three-dimensional (3-D) microjet flows. We fabricated single-jet and multi-jet arrays with 50 mu m diameter orifices and used micron-resolution particle image velocimetry (mu PIV) to capture two-dimensional (2-D) images of the flow field at different imaging planes. The data was subsequently used to obtain the out-of-plane (z-component) velocities, which play an important role in enhancing heat transfer at the impingement surface. The results from the reconstruction of the 3-D flow field offers new insights into the impact region of a single jet and optimized design of microjet cooling devices.