BACKGROUND AND PURPOSE No highly specific MR imaging features distinguishing ISCMs from primary cord masses have been described. Our purpose was to retrospectively compare peripheral enhancement features on postgadolinium MR imaging of ISCMs with primary intramedullary cord masses. MATERIALS AND METHODS A consecutive group of patients with firmly diagnosed ISCM (45 patients with 64 ISCMs) and...

Lagrangian PDF investigations are performed of the Sandia piloted flame E and the Cabra H2/N2 lifted flame to help develop a deeper understanding of local extinction, re-ignition and auto-ignition in these flames, and of the PDF models’ abilities to represent these phenomena. Lagrangian particle time series are extracted from the PDF model calculations and are analyzed. In the analysis of the r...

An investigation is carried out into the ranges of Damköhler number and Lewis number, less than unity, in which different forms of combustion phenomena arise within a non-premixed counterflow; cases that are symmetrical across the counterflow are chosen for study. These link oscillatory and steady propagation of flame edges, zero propagation speeds, isolated flame tubes, quenching and marginal ...

This work is dedicated to the analysis of the delicate details of the effect of upstream velocity fluctuations on the flame propagation speed. The investigation was carried out using the Sivashinsky model of cellularisation of hydrodynamically unstable flame fronts. We identified the perturbations of the steadily propagating flames which can be significantly amplified over finite periods of tim...

The objectives of the present study are the formulation of the models of flame front evolution capturing the effects of flame propagation in the prescribed non-stationary premixed gas flow field. The algorithm of real time simulations of flame evolution within frame of “flamelet” approach is offered to model shape of flame front propagating in the given non stationary gas flow fields. The algor...

FLAME, the Flexible API for Module-based Environments, is a proposed standard interface for the integration of parameterized hardware generators into high-level design tools. This work introduces two new developments: The FLAME Primitives Catalog describes the behavior and interface of a set of hardware functions suitable as primitives for automatic compilation. The FLAME Shared Access Conventi...

This paper reports on an experimental study of the influence of a nanosecond repetitively pulsed spark discharge on the stability domain of a propane/air flame. This flame is produced in a lean premixed swirled combustor representative of an aeronautical combustion chamber. The lean extinction limits of the flame produced without and with plasma are determined and compared. It appears that only...

Flame retardants, such as inorganic fillers or halogenated resins, are incorporated into composites either as additives or reactive materials. In order to improve processability and mechanical properties, as well as reduce smoke toxicity, a method is being developed to introduce highly effective, inexpensive flame retardant materials into thermoset resins. Superabsorbent polymers (SAP) can be l...

Understanding the dynamics and the stabilisation of flames is important for practical applications and for theoretical research. Here, to investigate the time-evolution of a Bunsen flame in a Poiseuille flow, we extend a G-equation-based kinematic model by accounting for flame stabilisation. The nonlinear G-equation is solved analytically using the methods of characteristics. The solution is th...

Laminar flame speeds of undiluted syngas (H2/CO) mixtures have been studied at atmospheric conditions using chemiluminescence and schlieren techniques for a straight cylindrical burner apparatus. A wide range of mixture composition, from pure H2 to 1/99 % H2/CO, has been investigated for lean premixed syngas flames. To achieve a better flame stabilization and reduce flame flashback propensity, ...