Multi-Beam Accelerator-Driven-Systems of Part I: Optimization on Thermal-Hydraulic design of target assembly

Integrated target module with a solid beam window, and cooled by reactor primary coolant is a good contender for Accelerator Driven System (ADS) and the cooling of the beam window is a key technique in it. The numerical analysis of two beam profiles (circular/double-circular scan) for the target assembly was performed by computational fluid dynamics (CFD) method, and a combing method was used to optimize the thermal-hydraulic design. The calculation results indicated that a nozzle was required to lower the maximum external surface temperature of the beam window to below 400 degrees C. This can be achieved by reducing the heat deposited densities or increasing the velocity in the main heat deposited zone without enhancing the heat convection at the window surface, this will effectively reduce the temperature, but without increasing the temperature difference in the beam window. The optimization results indicate that the maximum temperature of the beam window is 393.75 degrees C and 384.94 degrees C for the circular scan and the double-circular scan, respectively. Additionally, the maximum temperature difference is 23.0 degrees C and 17.1 degrees C for the circular scan and the double-circular scan, respectively.