半球向全发射率测量实验教学系统设计与开发  

Design and development of an experimental teaching system for measuring hemispherical total emissivity

作　　者：吴宇颂 田博宇 李辉[1,2] 许兆峰[1,2] 霍雨佳[1,2] 符泰然 WU Yusong;TIAN Boyu;LI Hui;XU Zhaofeng;HUO Yujia;FU Tairan(Department of Energy and Power Engineering,Tsinghua University,Beijing 100084,China;Key Laboratory for Thermal Science and Power Engineering of Ministry of Education,Tsinghua University,Beijing 100084,China)

机构地区：[1]清华大学能源与动力工程系,北京100084 [2]清华大学热科学与动力工程教育部重点实验室,北京100084

出　　处：《实验技术与管理》2024年第1期165-170,共6页Experimental Technology and Management

基　　金：国家自然科学基金(51976097)。

摘　　要：针对传统半球向全发射率测量教学实验装置测试精度不高、温度量程低的问题,该文基于稳态量热方法设计了高温半球向全发射率测量实验教学系统,进行了样品测试区域热量损失的校准,该系统具有方法原理简单、测试精度高等特点。通过测量获得不同温度下的材料半球向全发射率,便于同学们理解半球向全发射率与材料热辐射能力的相关性、光谱发射率与不同温度下的半球向全发射率的关联关系,实验测试结果可靠,满足热工系列课程研究型实验教学的需求。[Objective]Hemispherical total emissivity is a fundamental thermophysical parameter that describes the surface thermal radiation capability of materials and has important applications in various fields,such as energy power,aerospace,and new materials.In thermal engineering series courses,the introduction to the measurement of hemispherical total emissivity parameters is insufficient,and arrangements for teaching experiments on hemispherical total emissivity measurement are lacking.Devising approaches to help students better understand the concept of hemispherical total emissivity and its application in radiation heat transfer has always been difficult in the implementation of course knowledge.[Methods]To solve the problems of low measurement accuracy and limited temperature range in traditional teaching experimental devices for measuring hemispherical total emissivity,this study designs an experimental teaching system for measuring the hemispherical total emissivity at high temperatures based on the steady-state calorimetry method.The proposed system includes a vacuum chamber,vacuum pump,vacuum gauge,power supply,sample holder,voltmeter,ammeter,and temperature sensor.A hemispherical total emissivity calculation method based on steady-state calorimetry was established,and a calibration analysis for heat loss in the sample testing area was conducted.Based on theoretical formulas,the relation between hemispherical total emissivity and spectral emissivity,as well as the correlation between hemispherical total emissivity and material thermal radiation capability,were discussed.To verify the measurement performance of the hemispherical total emissivity teaching experimental device and calculation method,oxidized and unoxidized Ni–Cr high-temperature alloy samples were selected for testing,and the hemispherical total emissivity of samples at different temperatures was measured.[Results]The experimental results showed that the experimental measurement device has good measurement accuracy under high-temperature conditio

关 键 词：半球向全发射率 稳态热量法 实验教学 

分 类 号：TK39[动力工程及工程热物理—热能工程]