Results are reported from recent tests where hydrothermal flames spontaneously ignited in a Supercritical Water Oxidation (SCWO) Test Cell. Hydrothermal flames are generally categorized as flames that occur when appropriate concentrations of fuel and oxidizer are present in supercritical water (SCW); i.e., water at conditions above its critical point (218 atm and 374 °C). A co-flow injector was...

Title of dissertation: A FUNDAMENTAL STUDY OF BOUNDARY LAYER DIFFUSION FLAMES Ajay Vikram Singh, Doctor of Philosophy, 2015 Dissertation directed by: Professor Michael J. Gollner Department of Fire Protection Engineering Modeling the realistic burning behavior of condensed-phase fuels has remained out of reach, in part because of an inability to resolve complex interactions at the interface bet...

Tie-accurate simulation of turbulent flames in high Reynolds number flows is a challenging task since both fluid dynamics and combustion must be modeled accurately. To numerically simulate this phenomenon, very large computer resources (both time and memory) are required. Although current vector supercomputers are capable of providing adequate xesources for simulations of this nature, the high ...

The series of workshops on Measurement and Computation of Turbulent Nonpremixed Flames (TNF) is intended to facilitate collaboration and information exchange among experimental and computational researchers in the field of turbulent combustion. The emphasis is on fundamental issues of turbulence-chemistry interaction. In past workshops these issues have been explored through collaborative compa...

Unsteady simulations of stagnation point flames are conducted in order to study flame turbulence interactions in a relatively simple flow environment. Flame propagation is represented using a flamelet model called the G equation. Two subgrid models are used to close the filtered G equation. The effects of significant heat release on the turbulent flow and the effect of varying turbulence intens...

A three-dimensional (3-D) imaging system for studies of reactive and non-reactive flows is described. It can be used to reveal the topology of turbulent structures and to extract 3-D quantities, such as concentration gradients. Measurements are performed using a high repetition rate laser and detector system in combination with a scanning mirror. In this study, the system is used for laserinduc...

At a density near a few ×10 g cm, the subsonic burning in a Type Ia supernova enters the distributed regime (high Karlovitz number). In this regime, turbulence disrupts the internal structure of the flame, and so the idea of laminar burning propagated by conduction is no longer valid. The nature of the burning in this distributed regime depends on the turbulent Damköhler number (DaT ), which st...

Advances in high-performance computational capabilities enable scientific simulations with increasingly realistic physical representations. This situation is especially true of turbulent combustion involving multiscale interactions between turbulent flow, complex chemical reaction, and scalar transport. A fundamental understanding of combustion processes is crucial to the development and optimi...

Results of numerical modelling of turbulent non-premixed Methane/Hydrogen (1/1 by volume) flames issuing from a jet in hot coflow (JHC) are presented. The JHC burner is designed to emulate Moderate and Intense Low oxygen Dilution (MILD) combustion regime. A comparison between the measured and computed temperature and species profiles is presented for three flames with different oxygen content i...

The propagation of turbulent premixed flames influenced by the intrinsic hydrodynamic flame instability (the Darrieus-Landau instability) is considered in a two-dimensional case using the model nonlinear equation proposed recently by Bychkov [Phys. Rev. Lett. 84, 6122 (2000)]. The nonlinear equation takes into account both the influence of external turbulence and the intrinsic properties of a f...