Optimal design of a grid cathode structure in Spherically Convergent Beam Fusion device by response surface methodology combined with experimental design

A neutron production is very important to apply fusion energy through a spherically convergent beam fusion (SCBF) device as a portable neutron source and its rate is deeply dependent on the ion current. Also the ion current has a close relation with the potential well structure inside a grid cathode. This paper proposes a design method by varying the size of cathode rings to get an optimal grid cathode structure in a SCBF device. The optimization is based on the response surface methodology (RSM) and the full factorial design (FFD) is also applied to raise the precision of optimization and to reduce the iteration of experiment in the application of the RSM. The finite element method-flux corrected transport (FEM-FCT) method is employed to calculate the ion current. From the optimized model, the higher ion current is calculated and the deeper potential well is observed.