Use of Distributed Temperature Sensing Technology to Characterize Fire Behavior.

Area of Science:

• Environmental Science
• Engineering
• Remote Sensing

Background:

• Wildland fire characterization is crucial for safety and management.
• Existing methods for measuring fire behavior parameters have limitations in temporal and spatial resolution.
• Fiber optic sensing offers a potential new approach for real-time fire monitoring.

Purpose of the Study:

• To evaluate the performance of a specialized fiber optic cable with distributed temperature sensing (DTS) technology under wildland fire conditions.
• To assess the cable's ability to withstand extreme temperatures and repeated use in prescribed burns.
• To determine the potential of DTS technology for quantifying key fire behavior parameters.

Main Methods:

• A custom-designed 150-m 'fire cable' with three optical fibers (acrylate, copper, polyimide coatings) was deployed in grassland environments.
• Three prescribed fires were conducted with the fire cable installed.
• A DTS system continuously recorded temperature data from the cable at 3-second intervals and integrated temperatures every 50.6 cm.

Main Results:

• The fire cable demonstrated physical robustness and withstood repeated exposure to harsh fire conditions.
• Fiber coating materials endured temperatures up to 422 °C.
• Minimal changes in fiber attenuation ( -0.81 to 0.12 dB/km) were observed post-fire, indicating no significant signal degradation.

Conclusions:

• The fire cable and DTS technology show promise for accurately quantifying fire environment parameters like heat duration and rate of spread.
• Further research and analysis are necessary to fully establish the efficacy and response times of this technology.
• This study contributes to understanding DTS and fire cable capabilities for advanced fire behavior characterization at large scales.