Dynamical and statistical behavior of discrete combustion waves: a theoretical and numerical study
Naine Tarun Bharath1, Sergey A Rashkovskiy, Surya P Tewari
1Advanced Centre of Research in High Energy Materials (ACRHEM), University of Hyderabad, Prof C R Rao Road, Gachibowli, Hyderabad, Andhra Pradesh 500046, India.
Summary
Combustion waves in disordered systems are significantly influenced by their random structure. This study reveals how system heterogeneity affects burning rates and combustion mechanisms in pyrotechnic mixtures.
Area of Science:
- Physical Chemistry
- Materials Science
- Chemical Engineering
Background:
- Combustion waves in disordered systems are complex phenomena.
- Understanding the role of system structure is crucial for predicting combustion behavior.
Purpose of the Study:
- To theoretically and numerically investigate combustion waves in discrete one-dimensional disordered systems.
- To analyze the influence of system heterogeneity on combustion dynamics and kinetics.
- To validate a developed model against experimental data for gasless and thermite systems.
Main Methods:
- Theoretical modeling of reaction cell distances using a gamma distribution.
- Numerical simulations of combustion wave propagation.
- Analysis of experimental data from (Ti + xSi) and various thermite systems.
Main Results:
- The random structure of microheterogeneous systems critically impacts dynamical and statistical behavior due to nonlinear interactions with thermal waves.
- Burning rates of powder systems are highly sensitive to their internal structure.
- The developed model successfully reproduces experimental data for diverse pyrotechnic mixtures.
- Combustion in disperse systems occurs via a microheterogeneous, relay-race mechanism, driven by thermal effects and heterogeneity, even without microkinetic Arrhenius behavior.
Conclusions:
- System heterogeneity is a key factor governing combustion wave dynamics in disordered systems.
- The developed theoretical model provides a robust framework for understanding and predicting combustion in pyrotechnic materials.
- Combustion in disperse systems exhibits a thermal, microheterogeneous mechanism, independent of microkinetic Arrhenius laws.
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