Investigation of dynamics of hydrogen-rich flames, development of new methods for validation of mechanisms of chemical kinetics and for model reduction

• Applicant: Privatdozent Dr.-Ing. Viatcheslav Bykov
• Subject Area: Chemical and Thermal Process Engineering ; Energy Process Engineering ; Mathematics ; Theoretical Chemistry: Molecules, Materials, Surfaces
• Term: from 2017 to 2022
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 382408926

Nowadays, not only the development of practical devices, which utilize combustion of hydrocarbon fuels, but also theoretical research in the field of physics of combustion and detonation are based on the numerical treatment of mathematical models using detailed kinetics of oxidation reactions of hydrocarbon fuels. At present there is a number of kinetic mechanisms developed specifically to describe the high temperature combustion processes of hydrocarbon oxidation. These may include hundreds and thousands of elementary steps with their own reaction constants.However, direct and indirect experimental measurements of these reaction constants are very limited. Thus, development of an accurate and reliable mathematical model of combustion wave propagation still represents a very challenging task and any additional method of verification and validation of chemical reaction mechanisms is invaluable for modelling of combustion processes.In the proposed project, the authors suggest to develop a method for validation and verification of the hydrogen combustion mechanisms. This is because hydrogen combustion remains a hot topic due to applications for energy storage technologies and, therefore, simultaneously reduction of CO2 emissions. Particularly important is the development of mathematical combustion models for safety issues, where reliable mechanisms describing the transient regimes, non-stationary regimes typical for explosion-like processes, are required. Moreover, hydrogen oxidation represents the kernel sub-mechanism for all known detailed mechanisms of light and heavy hydrocarbon oxidation.At the same time numerical treatment of combustion processes in technical geometries and flow conditions are still beyond practical applications due to high dimensionality and the presence of large differences in the characteristic time and length scales. Dimensionality and stiffness of the system of governing equations complicates numerical treatment enormously and leads to very high CPU and memory storage requirements. Thus, the development of reduced kinetic mechanisms presents another key problem of the proposed study.The suggested methodology will be based on the investigation of the dynamical characteristics of nonlinear wave patterns, which emerge in complex combustion systems and on low-dimensional slow invariant manifolds developed in the reacting system state space. The successful realization of the project will open new perspectives in verification of mechanisms of chemical kinetics, significantly advance combustion theory and applications including industrial uses. The methods for automatic reduction of kinetic mechanisms will play a pivotal role in numerical computations for control and optimization of combustion processes of hydrocarbons in complex geometries and flow conditions.

• DFG Programme: Research Grants
• International Connection: Russia
• Co-Investigator: Professor Dr. Ulrich Maas
• Cooperation Partner: Privatdozent Dr. Vladimir Gubernov