作者：牛凯, 晋华, 张永波, 郑强, 张春一

作者单位：太原理工大学, 山西 太原 030024

关键词：导热系数;热探针;加热时间;电压;试样直径

摘要：

针对线热源理论自制的热探针在实际测定导热系数过程中所得结果受实验参数影响显著的问题,该文对加热时间、电压、试样直径3个实验参数展开研究,在不同的装置参数下测定乙二醇的导热系数,以探究三者对导热系数测定结果的影响及参数选取的最优区间。实验结果表明:热探针的最佳加热时间为40~60 s,最佳电压为1~2 V;电压2 V时可忽略试样直径对测定结果的影响;实验过程温度变化5℃时可显著降低试样对流引起的实验误差。研究结果可为热探针测定导热系数参数的选取提供可靠的数据参考,所得规律能有效降低热探针测定导热系数的误差。

Parameter experiment for thermal probe measuring apparatus

NIU Kai, JIN Hua, ZHANG Yongbo, ZHENG Qiang, ZHANG Chunyi

Taiyuan University of Technology, Taiyuan 030024, China

Abstract: Thermal probes have been widely used in liquid and granular materials. However, in actual measurement processes, the measurement results are significantly influenced by the experimental parameters of thermal probes made with the theory of linear heat source theory. Three experimental parameters, i.e., heating time, voltage and sample diameters, are studied in this paper. The heat conductivity coefficient of ethylene glycol is determined to explore how the above-stated three parameters influence the measured heat conductivity coefficient and the optimal parameter selection interval. The experimental results indicate that the optimal heating time is 40 s-60 s and the optimal input voltage is 1 V-2 V. When the voltage is below 2 V, the influence can be ignored. The experimental error reduces obviously when the temperature change is less than 5℃ during the experiment. This study has provided a reliable data reference for the measurement parameters of thermal probes and the measurement errors in heat conductivity coefficient of thermal probes can be slumped with the regularity obtained from the study.

Keywords: heat conductivity coefficient;thermal probe;heating time;voltage;sample diameter

2016, 42(6): 29-32  收稿日期: 2015-10-23;收到修改稿日期: 2015-11-24

基金项目: 国家自然科学基金项目(41372247)

作者简介: 牛凯(1990-),男,山西长治市人,硕士研究生,专业方向为岩土体渗流及环境效应。

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