Gregory Lyng

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We use the classical normal mode approach of hydrodynamic stability theory to define stability determinants (Evans functions) for multidimensional strong detonations in three commonly studied models of combustion: the full reactive Navier-Stokes (RNS) model, and the simpler Zeldovich-von Neumann-Döring (ZND) and Chapman-Jouguet (CJ) models. The determinants(More)
The frequency and severity of retinal hemorrhages were studied in 200 newborns within the first 72 hours of life. One hundred of the neonates were delivered instrumentally by either forceps (49 cases) or vacuum extraction (51 cases). Another hundred neonates were delivered spontaneously and served as controls. Both the highest and the lowest frequency of(More)
The rigorous study of spectral stability for ZND detonations was begun by J.J. Erpenbeck in [E1]. He used a normal mode analysis to define a stability function V (λ, η), whose zeros in Rλ > 0 correspond to multidimensional perturbations of a steady planar profile that grow exponentially with time. In [E3] he was able to prove that for large classes of(More)
Generalizing similar results for viscous shock and relaxation waves, we establish sharp pointwise Green function bounds and linearized and nonlinear stability for traveling wave solutions of an abstract viscous combustion model including both Majda’s model and the full reacting compressible Navier–Stokes equations with artificial viscosity with general(More)
It has long been a standard practice to neglect diffusive effects in stability analyses of detonation waves. Here, with the principal aim of quantifying the impact of these oft-neglected effects on the stability characteristics of such waves, we use numerical Evans-function techniques to study the (spectral) stability of viscous strong detonation(More)
There is a large body of literature on the problem of stability for inviscid shock waves and in particular for gas dynamics, see [2, 17, 3, 5, 6, 9, 10, 16, 4, 7, 21, 12, 13, 1, 14, 15, 24]. The purpose of this appendix is to calculate the Lopatinski determinant, or “stability function,” for the Euler equations of compressible gas dynamics. We describe two(More)