The Structure of Laminar Premixed H2-Air Flames at Elevated Pressures

Abstract

In high-pressure flames that occur in many practical combustion devices such as industrial furnaces, rocket propulsion and internal engine combustion, the assumption of an ideal gas is not appropriate. The present paper presents a model that includes modifications of the equation of state, transport and thermodynamic properties. The model is implemented into a Fortran program that was developed to simulate numerically one-dimensional planar premixed flames. The influence of the modifications for the real gas behavior on the laminar flame speed and on flame structure is illustrated for stoichiometric H2-air flames at initial pressures ranging from 0.1 to 100 MPa.

Detailed modeling of planar transcritical H2–O2–N2flames

“…More specifically, the crossing temperature is around 1400 K for atmospheric flames and around 2100 K at p = 100 atm. A remarkable feature of high pressure H 2 -Air flames is thus the high concentrations of the HO 2 radical as also discussed by El Gamal et al [5] …”

“…[2], Habiballah et al [3] and Candel et al [4]. Numerical simulations of high pressure planar flames have been performed by El Gamal et al [5], mixing layers by Okongo and Bellan [9], counterflow laminar flames by Saur et al [6], Ribert et al [7], and Pons et al [8], and turbulent flames by Zong and Yang [10], and Bellan [11]. More recent research involves supercritical combustion of oxygen in industrial configurations as studied by Oefelein [12], Zong and Yang [13], and Schmitt et al [14].…”

Numerical simulation of transcritical strained laminar flames

“…The SRK equation of state could thus solely be based on molecular potential parameters as the equation of state used by Saur [8] and El-Gamal [9]. This feature is closely related with the assumption of interaction potential in the form ǫφ(r/σ) -where ǫ and σ are the potential well depth and the collision diameter respectively -which underlies the corresponding states principle [37,48].…”

“…This motivates the study of strained laminar flames [1,2,3,4] associated with turbulent combustion models [5,6,7] in the context of nonideal reactive mixture. Following the work of Saur et al [8], El-Gamal et al [9], Ribert et al [10] and Pons et al [11,12], the purpose of this paper is to further study the influence of pressure driven nonidealities on H 2 -O 2 mixing layers and H 2 -O 2 flame structures.…”

“…The Soave-Redlich-Kwong equation of state is widely used for the modeling of transcritical flows, in particular by Ribert et al [10] and Zong and Yang [15,16] and yields a good representation of dense to dilute fluids. For radical species, the evaluation of attractive and repulsive terms of the equation of state uses molecular considerations similar to the one used by Saur et al [8] and El-Gamal et al [9].…”