Depth-resolved water temperature measurements using Raman LiDAR

Area of Science:

• Environmental Science
• Optical Sensing Technologies
• Fluid Dynamics

Background:

• Accurate temperature profiling is crucial for understanding water body dynamics and thermal processes.
• Traditional methods for temperature measurement can be invasive or lack spatial resolution.

Purpose of the Study:

• To demonstrate the capability of Raman LiDAR for non-invasive, depth-resolved temperature measurements in water.
• To evaluate the accuracy and spatial resolution of this technique for characterizing temperature profiles.

Main Methods:

• Utilized a Raman LiDAR system for remote sensing of water temperature.
• Conducted experiments in a 5-meter laboratory water pipe to simulate controlled conditions.
• Collected backscattered Raman signals to infer temperature at various depths.

Main Results:

• Successfully retrieved non-homogeneous temperature profiles in the laboratory water pipe.
• Achieved a temperature accuracy ranging from 0.35°C to 0.85°C.
• Demonstrated a spatial position resolution of 28 cm for the temperature measurements.

Conclusions:

• Raman LiDAR is a viable technique for accurate, depth-resolved temperature measurements in water.
• The system shows potential for environmental monitoring and industrial applications requiring thermal profiling.
• Further development could enhance resolution and extend applicability to diverse aquatic environments.