Influence of protection tube on thermocouple effect length
Thermocouples are often equipped with ceramic protection tubes. The existence of the tube changes the heat transfer of thermocouple wires. It will change the bead temperature, i.e., the measurement temperature. The one-dimensional axial heat transfer program for the thermocouple with the protection...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
| Published: |
Elsevier
2021-08-01
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| Series: | Case Studies in Thermal Engineering |
| Subjects: | |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S2214157X21003415 |
| _version_ | 1818438852784685056 |
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| author | Jiuzhao Sun Budong Liu Peichen Xu Peiyong Wang |
| author_facet | Jiuzhao Sun Budong Liu Peichen Xu Peiyong Wang |
| author_sort | Jiuzhao Sun |
| collection | DOAJ |
| description | Thermocouples are often equipped with ceramic protection tubes. The existence of the tube changes the heat transfer of thermocouple wires. It will change the bead temperature, i.e., the measurement temperature. The one-dimensional axial heat transfer program for the thermocouple with the protection tube is developed. The accuracy of the program is validated by three-dimensional CFD simulations. The influence of the protection tube on the bead temperature and the effect length is studied with the one-dimensional program. The existence of the tube lowers the bead temperature. The smaller the wire protruding length from the tube, the larger the bead temperature drop. The effect of the tube thermal properties such as the thermal conductivity and emissivity on the thermocouple temperature is studied. The properties have strong effect on the tube temperature profile but their effect on the bead temperature is slight. An analytical method is developed to calculate the effect length of the thermocouple with the protection tube. The error of the method is less than 12% compared with the numerical result for the tested cases. The tube existence increases the effect length. Increasing the wire protruding length from the tube, the tube influence on the effect length decreases. |
| first_indexed | 2024-12-14T17:47:09Z |
| format | Article |
| id | doaj.art-e9a84dd68e454c5e9ee54b67e4f375b5 |
| institution | Directory Open Access Journal |
| issn | 2214-157X |
| language | English |
| last_indexed | 2024-12-14T17:47:09Z |
| publishDate | 2021-08-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Case Studies in Thermal Engineering |
| spelling | doaj.art-e9a84dd68e454c5e9ee54b67e4f375b52022-12-21T22:52:43ZengElsevierCase Studies in Thermal Engineering2214-157X2021-08-0126101178Influence of protection tube on thermocouple effect lengthJiuzhao Sun0Budong Liu1Peichen Xu2Peiyong Wang3School of Aerospace Engineering, Xiamen University, Xiamen, 361102, ChinaSchool of Aerospace Engineering, Xiamen University, Xiamen, 361102, ChinaSchool of Aerospace Engineering, Xiamen University, Xiamen, 361102, ChinaCorresponding author.; School of Aerospace Engineering, Xiamen University, Xiamen, 361102, ChinaThermocouples are often equipped with ceramic protection tubes. The existence of the tube changes the heat transfer of thermocouple wires. It will change the bead temperature, i.e., the measurement temperature. The one-dimensional axial heat transfer program for the thermocouple with the protection tube is developed. The accuracy of the program is validated by three-dimensional CFD simulations. The influence of the protection tube on the bead temperature and the effect length is studied with the one-dimensional program. The existence of the tube lowers the bead temperature. The smaller the wire protruding length from the tube, the larger the bead temperature drop. The effect of the tube thermal properties such as the thermal conductivity and emissivity on the thermocouple temperature is studied. The properties have strong effect on the tube temperature profile but their effect on the bead temperature is slight. An analytical method is developed to calculate the effect length of the thermocouple with the protection tube. The error of the method is less than 12% compared with the numerical result for the tested cases. The tube existence increases the effect length. Increasing the wire protruding length from the tube, the tube influence on the effect length decreases.http://www.sciencedirect.com/science/article/pii/S2214157X21003415ThermocoupleGas temperature measurementBead temperatureProtection tubeEffect length |
| spellingShingle | Jiuzhao Sun Budong Liu Peichen Xu Peiyong Wang Influence of protection tube on thermocouple effect length Case Studies in Thermal Engineering Thermocouple Gas temperature measurement Bead temperature Protection tube Effect length |
| title | Influence of protection tube on thermocouple effect length |
| title_full | Influence of protection tube on thermocouple effect length |
| title_fullStr | Influence of protection tube on thermocouple effect length |
| title_full_unstemmed | Influence of protection tube on thermocouple effect length |
| title_short | Influence of protection tube on thermocouple effect length |
| title_sort | influence of protection tube on thermocouple effect length |
| topic | Thermocouple Gas temperature measurement Bead temperature Protection tube Effect length |
| url | http://www.sciencedirect.com/science/article/pii/S2214157X21003415 |
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