Experimental and Modeling Study on the Ignition Kinetics of Nitromethane behind Reflected Shock Waves

Area of Science:

• Combustion Chemistry
• Chemical Kinetics
• Energetic Materials

Background:

• Nitromethane (NM) is a simple nitroalkane fuel with potential as a propellant and fuel additive.
• Understanding NM combustion is crucial for developing kinetic models of nitro-containing energetic materials.

Purpose of the Study:

• To experimentally and computationally investigate the ignition kinetics of nitromethane (NM).
• To supplement the experimental database for kinetic mechanism development of NM.
• To analyze ignition delay times (IDTs) of NM at high fuel concentrations.

Main Methods:

• Measurements of NM ignition delay times (IDTs) using a high-pressure shock tube.
• Experimental conditions: 900–1150 K, 5–10 bar, equivalence ratios of 0.5, 1.0, and 2.0.
• Kinetic modeling including brute-force sensitivity, chemical explosive mode, and reaction path analyses.
• Derivation of a skeletal NM mechanism using directed relation graph-based methods.

Main Results:

• Experimental IDTs of NM were measured under various high-pressure conditions.
• Sensitivity and reaction path analyses identified key reactions governing NM ignition.
• A skeletal mechanism was developed, showing good predictive accuracy for NM ignition and flame speeds.

Conclusions:

• The study provides valuable experimental data and kinetic insights into NM combustion.
• The derived skeletal mechanism improves the understanding and modeling of nitroalkane fuels.
• This work supports the development of detailed kinetic models for nitro-containing energetic materials.