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对试件形状对利用ＩＨＣＰ原理测算物体导热系数方法的影响进行研究．在不同形状试件的无因次瞬态温度分布特性、导热系数敏感度系数表达式及变化规律、物理和数学模型描述误差等方面进行了理论分析，为试件形状的选择提供了理论依据和指导原则．还利用实验对理论分析结果加以验证，并对实际测算中的关键环节进行探讨．结果表明，对导热性能迥然不同的二种材质（导热系数数量级为１０－１～１０Ｗ／（ｍ·Ｋ）的聚氨酯和不锈钢），利用球体试件测算ｋ值的精确度最高，其测算值最大误差εｍａｘ≤３．６０％；无限长圆柱次之，εｍａｘ＜４．２０％；无限大平板更次之，εｍａｘ＜５．４４％．
The effect of the shape of the test piece on the method of measuring the thermal conductivity of an object using IHCP principle is studied. The dimensionless transient temperature distribution, the expression and variation of the coefficient of thermal conductivity sensitivity, the description of the physical and mathematical model errors are analyzed theoretically, which provide the theoretical basis for the selection of the shape of the specimen. Guiding Principles. Also use the experimental results to verify the theoretical analysis, and the actual measurement of the key aspects are discussed. The results show that for the two kinds of materials with very different thermal conductivity (polyurethane and stainless steel with thermal conductivity of 10-1 ~ 10W / (m · K)), the accuracy of k value measured by sphere specimen is the highest, Error εmax≤3.60%; infinite cylinder followed by, εmax <4.20%; infinite flat plate followed, εmax <5.44%.