Two-dimensional detailed numerical simulation of ammonia/hydrogen/air detonation: hydrogen concentration effects and transverse detonation wave structure

• Published in: Shock waves Vol. 34; no. 2; pp. 139 - 154
• Main Authors: Kohama, S., Ito, T., Tsuboi, N., Ozawa, K., Hayashi, A. K.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01-04-2024; Springer Nature B.V
• Subjects: Acoustics; Ammonia; Cellular structure; Condensed Matter Physics; Detonation waves; Dynamic structural analysis; Engineering; Engineering Fluid Dynamics; Engineering Thermodynamics; Flow stability; Fluid- and Aerodynamics; Heat and Mass Transfer; Hydrogen; Mixing ratio; Nonlinear dynamics; Original Article; Propagation velocity; Structural stability; Thermodynamics; Transverse waves; Wave propagation; Ammonia; Numerical simulation; Detailed chemical reaction; Detonation structure
• ISSN: 0938-1287; 1432-2153
• DOI: 10.1007/s00193-024-01181-6

Numerical simulations on ammonia/hydrogen/air detonation are performed using a detailed reaction model to investigate the cellular instability and detonation dynamics as a function of hydrogen content. The UT-LCS model that includes 32 species and 213 elementary reactions is used in the present simulations. The fifth-order target compact nonlinear scheme captured the unstable detonation dynamics and the complicated flow structure including the propagation of a sub-transverse wave. The simulation performed with different hydrogen dilutions shows that the detonation propagates at the Chapman–Jouguet velocity for all cases, and the cell size for the ammonia/hydrogen mixing ratio
α
=
0.3
becomes approximately 10 times larger than that for
α
=
1.0
(hydrogen/air mixture). A transverse detonation produces a finescale cellular structure on the computed maximum pressure history. This complex shock formation is similar to those of a spinning detonation and two-dimensional propane/oxygen detonation. The cellular irregularity increases with decreasing hydrogen content because ammonia destabilizes the detonation cellular structure with a reduced activation energy of more than approximately 8.