A Temperature Measurement and System Identification Method for Confined Cavity Explosions Based on an Improved Type C...

Area of Science:

• Engineering
• Materials Science
• Physics

Background:

• Confined cavity explosions generate extreme conditions (high-speed fragments, shock waves) posing challenges for temperature measurement.
• Accurate temperature field reconstruction is crucial for understanding post-explosion dynamics but is complicated by nonlinear, multi-field coupling.

Purpose of the Study:

• To develop a robust temperature measurement system for confined cavity explosions.
• To propose a system identification method for reconstructing the post-explosion temperature field.

Main Methods:

• An improved type C thermocouple sensor with optimized alloy strip widths and an alumina insulating layer was designed for enhanced durability.
• A wedge-shaped alumina ceramic piece was incorporated to improve the structural stability of the thermocouple probe.
• A system identification method using the least squares approach was employed to construct a polynomial temperature field model.

Main Results:

• The improved thermocouple sensor demonstrated high survivability and reliable measurements under extreme explosive conditions.
• The reconstructed temperature field model achieved high fitting accuracy, effectively describing temperature distribution from limited data points.
• Experimental validation confirmed the sensor's robustness and the identification method's accuracy.

Conclusions:

• The developed thermocouple sensor is suitable for harsh environments in confined cavity explosions.
• The proposed system identification method accurately reconstructs temperature fields, aiding in understanding explosion dynamics.
• This research offers a reliable approach for temperature measurement and analysis in explosive events.