In machinery, aerospace, electric power and other industries, the need of metal surface temperature monitoring is very common, such as power cable lines, high temperature steam pipes and so on. Through temperature monitoring, other physical quantities marked by temperature could be analyzed.
Figure 1. Oil bath pot with a pure copper sample in it
Figure 1 shows the temperature test using the constant temperature oil bath pot. Temperature measurement is carried out by OSI-S and the layout of optical fiber is embedded type. Nine temperature test points are set.
Figure 2. Measurement result of OSI-S
Figure 3. Temperature fitting curve
| Temperature /℃ | 40.2 | 49.8 | 59.7 | 69.6 | 79.8 | 89.9 | 99.7 | 109.6 | 119.7 |
| Relative deviation / % | 0.6456 | 0.1363 | 1.3749 | 2.0471 | 1.1500 | 1.2377 | 0.4624 | 0.7353 | 0.6264 |
Table 4. Measurement deviation
The result that temperature fluctuations are small along the optical fiber during measurement indicates the effectiveness and rationality of embedded optical fiber measurement. The maximum relative deviation between average of each measured temperature and actual temperature is less than 2%(Figure 2、3、4).The measurement system is of high stability and the accuracy can reach ±0.1℃.