Numerical design and optimization of cooling system for 2 MeV traveling wave accelerator

Eliminating or reducing thermal deformation of an accelerator structure (caused by microwave power dissipated on the walls of RF cavities) to insure resonance frequency is an important topic in the design of the structure. A civil accelerator for killing anthrax bacilli must be small and compact, and so must its cooling system. This paper introduces the design and optimization of a cooling structure for an 0.57 m long, 2 kW, disk-loaded waveguide accelerator structure, for which the temperature distribution is required to be 30±3°C. All the parameters have been calculated and optimized by means of FEM (the Finite Element Method). The simulation is accomplished with software called I-DEAS (Integrated Design, Engineering, Analysis System). An optimized structure with a jacket style cooling chamber has been designed. The outside wall of the jacket is made of stainless steel and its external diameter is φ 118 mm. The flux of the cooling water is as small as 0.45 ton/hour. As a result, the temperature nonuniformity of the accelerator tube is better than ±2.5°C. The system is also very robust against surrounding temperature shifts. The cooling system has been installed in a 2 MeV accelerator, and the facility is running well.