The heat transfer performance of metal hydride reactors is poor.To solve this problem,Taguchi methods was used to optimize the design parameters of metal hydride reactors equipped with helical coil heat exchanger.A three-dimensional multi-physics model for the metal hydride reactor was proposed and solved using the commercial software package COMSOL Multiphysics V4.4.Some typical combinations of structural parameters for helical coil tubes were selected by using Taguchi methods,and the performance of the reactors with different helical coil tubes was evaluated by numerical simulations based on the reactor model.The analysis results indicated that the performance of the metal hydride reactor equipped with the helical coil heat exchanger was better because the heat transfer coefficient and the heat transfer area of the helical coil heat exchanger were larger in compared with the straight tube.As the pitch number of the helical coil (N) and the minor radius of the helical coil (do) increased,the gravimetric heat storage rate (GHSR) increased.However,the major radius of the helical coil (D) had a little effect on the reactor performance.The optimal parameters of the reactor wereDof 32 mm,Nof 6 anddoof 8 mm, and accordingly the maximum value of GHSR was 62.90 W/kg
