Simulating interactions of detonation, ionization chemistry, and magnetohydrodynamics

摘要

Detonation engines have the potential to remove NO_x emissions from combustion-based power generation by using high-temperature oxyfuel combustion. A magnetohydrodynamic (MHD) generator can directly extract power from ionized gases behind the detonation front (via the Lorentz force). This eliminates moving components found in gas turbine engines unable to withstand high temperatures. Modeling detonations coupled with MHD requires the simultaneous consideration of interactions between compressible flow, chemical reactions, and an electromagnetic field. This is achieved by coupling a Riemann solver, implicit ordinary differential equation integrators, and a Galerkin finite-element solver, which respectively solve the Euler, stiff chemical kinetics, and decoupled Maxwell equations. Each solver is separately verified and validated, and the coupled system is validated with literature results. Simulations of hydrogen and methane oxyfuel combustion are performed over a range of parameters to determine potential power extraction and emissions. To increase the efficiency of MHD, seed particles are typically necessary to increase a fluid's electrical conductivity through ionization. Therefore, impact of seed composition and quantity is also assessed. These results provide insight into the complex parasitic interactions between detonation, ionization, and MHD effects.