THERMAL ANALYSIS AND OPTIMIZATION OF HIGH-POWER BEAM DEPOSITION TARGET COOLING HEAT SINK FOR ACCELERATOR RADIOISOTOPES APPLICATION

This paper studies thermal performance of hybrid slot jet/minichannel heat sink for radioisotope preparation application using a 3D numerical model. The influence of geometry dimensions (channel shape, channel bottom structure, channel number, and channel length) is discussed. Results indicate that the local convection thermal resistance of hybrid module is gradually increasing along with flow direction; strong vortices are generated in the impingement region and further extend in the channel region; the presence of channel walls in the impingement region contributes to improvement of cooling performance. Compared with rectangular channels, in trapezoidal channels vortices away from the heated surface result in the enhancement of overall thermal resistance. The convex bottom surface possesses a higher overall thermal resistance due to the elevation of thermal-conduction resistance. Finally, for the high-power (∼ 3000 W), ultra-high heat flux (average ∼ 1000 W/cm2) conditions, flat bottom surface, rectangular-shape, 40-mm-long channel, 7-channel hybrid module is chosen to dissipate heat.