【作者】 曾悠兵；

【导师】 李艳宁；

【作者基本信息】 天津大学 ， 测试计量技术及仪器， 2010， 硕士

【摘要】 能源问题是当今社会的主要问题,节能已越来越受到人们的普遍关注。节能的主要途径之一是使用绝热材料,而材料的绝热性能是由其本身的导热系数决定的。导热系数越小,材料的绝热和保温性能就越好。导热系数测量在节能材料的研究、开发和生产中起着极为重要的作用。常见的导热系数测量方法有稳态法和瞬态法。稳态法中常用的方法是护热平板法,但现有护热平板法导热系数测定仪未能很好地解决系统的热平衡、功率补偿和自动化测量等关键技术,这就影响了测量的准确度和效率；同时,稳态法测量还具有测量时间长和测量范围小等固有缺点。本课题利用算法、模型修正和软件对现有护热平板法导热系数测定仪进行了改进和完善,很好地解决了其热平衡、功率补偿和自动化测量等关键技术；同时针对稳态法测量的固有缺点,利用瞬态平面热源技术初步开发了基于瞬态法的导热系数测定仪并对其传感器探头和测量电路等关键技术进行了研究。本论文完成的主要工作有：1、介绍了导热系数的基本概念和测量方法,概述了护热平板法和瞬态平面热源技术法导热系数测定仪的发展现状和存在的问题；2、阐述了护热平板法和瞬态平面热源技术法导热系数测定仪的测量原理；3、研究了护热平板法导热系数测定仪的热平衡和功率补偿等关键技术并给出了其修正方法,有效提高了测量结果的准确度；4、给出了护热平板法导热系数测定仪的系统稳定状态判定方法,提高了测量的效率和自动化程度。5、设计编写了护热平板法导热系数测定仪基于Labview平台的全套测控软件,能实现数据的采集及处理、参量控制、报表生成及打印等各种功能,并提供友好的人机交互界面；6、利用瞬态平面热源技术初步开发了基于瞬态法的导热系数测定仪并搭建了其样机,设计了其传感器探头和测量电路,并对相关数据处理进行了研究；7、对改进的护热平板法导热系数测定仪的热平衡、功率补偿和测控软件进行了实验测试并总结了其优点；对瞬态平面热源技术导热系数测定仪的传感器探头和测量电路进行了实验分析并对各种材料的导热系数进行了测量。8、指出了本课题存在的问题和需要改进的地方。更多还原

【Abstract】 Today, as energy becomes one of the key issues of the world, more and more attention has been paid on energy saving. One of the main ways to save energy is the use of thermal insulation material. The material’s thermal insulation property is determined by its Thermal Conductivity Coefficient (TCC). The material with low TCC normally has good heat insulation. And the measurement of TCC plays an important role in the research, development and manufacture of the thermal insulation material. There are mainly two methods to measure the TCC, the steady state method and the transient method. At present, the GHP (Guarded Hot Plate method), which belongs to steady state method, has been widely used. But its three key technologies: the thermal equilibrium, the power compensation and the automatic measurement, which can affect the measurement accuracy and efficiency, have not been well resolved; Meanwhile, the steady state method has some disadvantages such as the fixed measurement time and the narrow measurement range.In this study, the GHP thermal conductivity coefficient measuring instrument has been improved with the use of Labview software, optimization algorithm and model correction, and its key technologies of the thermal equilibrium, the power compensation and the automatic measurement have been intensively investigated; Besides, the transient thermal conductivity coefficient measuring instrument based on the TPS(Transient Plane Source technique) has been developed with attentions paid to the TPS senor design and the measuring circuit.The main work of this thesis is as follows:1. The basic concepts and measurement methods of TCC was introduced, the status and problem of GPH and TPS thermal conductivity coefficient measuring instrument was described.2. The measurement principle of GPH and TPS thermal conductivity coefficient measuring instrument was described.3. The correction methods of thermal equilibrium and power compensation for the GHP thermal conductivity coefficient measuring instrument system were researched, and that effectively improved the instrument’s accuracy. 4. Corresponding methods to determinate the system steady state of GHP thermal conductivity coefficient measuring instrument was provided, which greatly increased its measuring efficiency and the degree of automation.5. The complete set of measure and control software for GHP thermal conductivity coefficient measuring instrument system was designed, it can do the jobs of Data Acquisition and Processing, parameters controlling, measurement report generating and so on.6. The TPS thermal conductivity coefficient measuring instrument and its whole hardware are initially developed, then the TPS senor and the measuring and controlling circuit were designed, finally its software was developed and gave some data processing methods.7. Some experiments are carried out. The accuracy and feasibility of thermal equilibrium compensation method, power correction method and automatic measurement algorithm of GHP thermal conductivity coefficient measuring instrument were tested and verified; the TPS senor and the measuring and controlling circuit of TPS thermal conductivity coefficient measuring instrument were tested, some measure results of kinds of material’s thermal conductivity coefficient were gave.8. The problems and the further research direction of this paper are pointed out.更多还原