Experimental study of the thermal and mechanical performance of a spoke-wheel cryogenic support

A special spoke-wheel cryogenic support structure was introduced, with the experimental study of its thermal and mechanical performance of different materials and different spoke quantity and cross-section shape. The study included thermal conductivity experimental measurements of both polyether-ether-ketone (PEEK) and glass fiber reinforced plastic (GRP) material, thermal resistance measurements and the mechanical tensile failure tests of a variety of support wheels which have different structural forms of PEEK and GRP. The various experimental results were analyzed and compared, with the measurement error analysis. The results show that, when the temperature is below 200K, the thermal conductivity of the PEEK material is less than that of the GRP material, but they are almost the same above 200K. The thermal resistance of the support wheel decreases with the increase of the number of spokes and the spoke cross-sectional area, and the measured thermal resistance is a comprehensive result of the solid thermal conduction and thermal radiation. The mechanical performance of the support wheel is improved by the increase of the number of spokes and the spoke cross-sectional area, and the load bearing capability of the support of the GRP material is larger in the radial direction than in the axial direction, while that of the PEEK material is nearly same in both directions. That is mainly due to the anisotropic properties of GRP material. Eventually, the support wheel of PEEK material with 6 ribbed spokes is the best choice by integrating thermal and mechanical performance test results.