2017 Volume 10 Issue 4 Pages 282-287
Thermocouples are used to measure high temperature in process and steel industries. To measure high temperature gas, thermocouples should be inserted deeply enough; commercial specification documents recommend at least 5 times the diameter of sheath or more. This paper analyzes the effect of insertion length on thermocouple outputs in high temperature gas measurement. The theoretical evaluation is revised to include the radiation effect in the authors' previous work presented in SICE AC 2015 and compared with experimental data in a heating furnace more precisely than the work presented in SICE AC 2016.