【摘要】 运用稳态径向热流法对液氮温度下聚氨酯泡沫的热导率进行了测定 ,根据 GJB 1875 - 94建立的试验装置确保了使用径向量热法的前提条件。在液氮温度下聚氨酯泡沫的热导率可以达到 0 .86× 10 - 2 W/ m· K ,结果表明 :此材料在液氮的输运系统中是一种优良的绝热材料。另外 ,对聚氨酯泡沫的导热机理进行了讨论 ,最后对试验进行了误差分析 ,得到的最大相对误差为 4 %。更多还原

【Abstract】 Thermal conductivity of polyurethane foams was measured under liquid nitrogen temperature through the steady cylindrical method. The experimental set-up was built according to GJB1875-94, which ensured the condition of steady cylindrical method. Under liquid nitrogen temperature, the thermal conductivity can be reduced to 0.86×10 -2 W/m·K, which indicates that polyurethane foam is an excellent type of insulation material in system of transportation and storage for liquid nitrogen. In addition, heat transfer mechanisms were discussed in the paper. At last error analysis was made for the experimental result, the maximal value of which is 3%.更多还原