Abstract: Regenerator is one of the crucial components of Stirling engine. A unit cell model of Ni foam was developed based on the sphere-centered open-cell tetrakaidecahedron which was put forward by Mo Bai. Using this model, the correlation of poredensity, pore diameter and porosity was quantitatively derived. The flow of working gas in stainless steel wire mes (porosity: 0.62~0.83) regenerator and Ni foam (porosity: 0.94~0.98) regenerator was numerically simulated respectively based on the 2-D computational domain of regenerator. The analytical comparison of the above two filler' heat transfer coefficient, pressure drop, and resistance coefficient was conducted. It is shown that the amplitude of pressure drop between inlet and outlet of Ni foam regenerator is 1/400 of stainless steel wire mesh regenerato′s, while the heat transfer coefficient is only 1/5. At last, the parameter Nu/C^1/3_f was put forward to evaluate the fille′s comprehensive performance. The comparison results show that the Ni foam has the better comprehensive performance than the stainless steel wire mesh, so it has the potential of being used as there generator′s filler of Stirling engine.

Key words: Stirling engine, regenerator, Ni foam, stainless steel wire mesh, numerical simulation, comprehensive performance