Optical filter-fiber combination based infrared measurement device for surface temperature measurement

Area of Science:

• Plasma Physics
• Fusion Energy
• Diagnostic Techniques

Background:

• Neutral Beam Injection (NBI) is crucial for heating in fusion devices like EAST.
• Traditional thermocouples have limitations in NBI monitoring due to contact interference.
• Non-contact infrared thermometry offers improved reliability and reduced malfunction risk.

Purpose of the Study:

• To implement and validate remote infrared temperature measurement using optical fibers for the EAST-NBI diagnostic system.
• To assess the feasibility and accuracy of optical fiber-based infrared thermometry in a fusion environment.

Main Methods:

• Utilized remote infrared thermometers coupled with optical fibers for non-contact temperature monitoring.
• Conducted tests under EAST-NBI working conditions.
• Performed atmospheric propagation simulations to quantify absorption effects.

Main Results:

• Detector response aligned with theoretical predictions.
• Atmospheric absorption was found to be significant within specific wavelengths.
• Temperature measurement error remained within 1% for temperatures above 200°C.

Conclusions:

• Remote infrared thermometry via optical fibers is a viable and accurate method for monitoring EAST-NBI components.
• The system meets diagnostic requirements for the 200-600°C temperature range.
• Accounting for atmospheric absorption is essential for precise remote temperature measurements.