An anisotropic porous media model for crycooler regenerator was established. Based on the thermophysical properties of available heat capacity
axial thermal conductivity
and performance parameters of regenerator effectiveness and regenerator performance factor
the regenerator heat transfer performances were optimized under different regenerator geometries and properties with numerical simulation. The simulation results indicate that the cooling power enhances while the regenerator mesh specific heat capacity or density increases
and gets lower when the mesh specific heat capacity fixes and penetration depth becomes larger; the available heat capacity grows but cooling power reduces with the ratio of axial and transverse thermal conductivity(a)increased. While a is taken as 0.1
the cooling power is 0.5-2.0 W higher than the case of isotropy
which demonstrates that if the factor anisotropic is not taken into account the cooling power obtained from numeration arises on the low side. The meshes with relatively lower thermal conductivity or measures are selected to weaken the axial thermal conductivity to reduce the axial heat loss. Furthermore
the filling scale with different mesh geometry(such as of 75% 200 twill and 25% 250 twill)as well as multi-segment regenerator with stainless steel filled at the cold end enhance the regenerator effectiveness and regenerator performance factor.
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references
URI B N, DAN M. Low cost and high performance screen laminate regenerator matrix[J]. Cryogenics, 2004, 44(6/8): 439-444.
MURALIDHAR K, SUZUKI K. Analysis of flow and heat transfer in a regenerator mesh using a non-Darcy thermally non-equilibrium model[J]. Int J Heat and Mass Transfer, 2001, 44(13): 2493-2504.
GAO Fan, HE Yaling, LIU Yingwen. Numerical simulation of pressure drop characteristic in mesh regenerator under oscillating flow[J]. Journal of Engineering Thermophysics, 2008, 29(4): 668-670.
LEWIS M A, KURIYAMA T, KURIYAMA F, et al. Measurement of heat conduction through stacked screens[J]. Advances of Cryogenic Engineering, 1998, 43(B): 1611-1618.
SWIFT G W. Thermoacoustic engines[J]. J Acoust Soc Am, 1988, 84(5): 1145-1180.
NAM K, JEONG S. Measurement of cryogenic regenerator characteristics under oscillating flow and pulsating pressure[J]. Cryogenics, 2003, 43(10/11): 575-581.
NAM K, JEONG S. Investigation of oscillating flow friction factor for cryocooler regenerator considering cryogenic temperature effect[J]. Cryogenics, 2005, 45(12): 733-738.