A novel parameter for evaluating the multidimensional wave structures and stability of gaseous detonations

We numerically investigate multidimensional detonation wave structure and stability using the reactive Euler equations with detailed hydrogen chemistry and boundary-layer-induced loss source terms. The effects of initial pressure, argon dilution, and reaction mechanism are examined, and three distinct transverse wave structures are identified, namely weak, transitional, and strong transverse wave structures. Analysis of one-dimensional Zeldovich–von Neumann–Döring profiles and dimensionless D–κ curves indicates that transverse wave type is primarily controlled by the degree of energy concentration. A novel parameter ι is introduced to characterize the dimensionless D–κ relationship and to delineate boundaries between transverse wave structure regimes. By combining the propagation characteristics of transverse wave structures with the correlation between the parameter ι and the length ratio of the induction zone to the reaction zone contained in the stability parameter χ, it is indicated that transverse wave structures reflect detonation stability. Detonations exhibiting strong transverse wave structures are the least stable, whereas those with weak transverse wave structures are the most stable. The results reveal that velocity deficits induced by non-ideal conditions can decrease the value of the ι parameter. When velocity deficits cause a substantial change in ι that triggers a transition of the transverse wave structure, leading to a detonation structure dominated by strong transverse waves, an anomalous pressure rise is observed.