The interaction of a vortex pair with a premixed flame serves as an important prototype for premixed turbulent combustion. In this study, we investigate the interaction of a counterrotating vortex pair with an initially flat premixed methane flame. We focus on characterizing the mechanical nature of the flame-vortex interaction and on the features of the interaction strongly affected by fuel eq...

Large eddy simulation of a three-dimensional spatially developing transitional free methane non-premixed flame is performed. The solver of the governing equations is based upon a projection method. The Smagorinsky model is utilized for the turbulent subgrid scale terms. A global reaction mechanism is applied for the simulation of methane/air combustion. Simulation results clearly illustrate the...

Blast furnace gas is the byproduct of smelting steel production process, and is the important secondary energy source. It is can be used as fuel for engines to generate electricity for most middle and small steel enterprises. In order to understand the combustion mechanism and provide the basis for the design of blast furnace gas engine,premixed laminar combustion experiments of the blast furna...

BACKGROUND Microemulsion propofol produces more frequent and severe pain upon injection than lipid emulsion propofol. This study examined the analgesic effect of lidocaine-premixed microemulsion propofol in patients pretreated with remifentanil. The induction of anesthesia with this combination was compared with microemulsion propofol accompanied with either remifentanil or lidocaine. METHODS...

A parallel adaptive mesh refinement (AMR) algorithm is proposed for predicting turbulent non-premixed combusting flows characteristic of gas turbine engine combustors. The Favre-averaged Navier-Stokes equations governing mixture and species transport for a reactive mixture of thermally perfect gases in two dimensions, the two transport equations of the k-ω turbulence model, and the time-average...

The article presents the data related to the flame acquisitions in a liquid-fuel gas turbine derived burner operating in non-premixed mode under three different equivalence fuel/air ratio, which corresponds to a richer, an intermediate, and an ultra-lean condition, near lean blowout (LBO). The data were collected with two high speed visualization systems which acquired in the visible (VIS) and ...

An efficient time accurate algorithm with great potential in LES simulations of non-premixed flames is presented for numerical simulations of low-Mach number variable density flows. The algorithm is based on a segregated solution formalism in the class of pressure-correction methods. It shows good conservation properties and returns stable results, regardless of the difference in density betwee...

Combustion instability of O2/kerosene, O2/kerosene/hydrogen, and O2/kerosene/hydrogen spray flame is numerically studied. The numerical results of combustion self-oscillation are consistent with the historical experiments. Hydrogen is helpful to stabilizing oxygen/hydrocarbon combustion. High gas injecting velocity of the coaxial injector would increase the combustion stability. Contrary to the...

An idealized model for turbulent premixed flames is introduced. It consists of a scalar advection-reaction-diffusion equation that describes the interaction of a thin flame with a turbulentlike flow field acting on two separate scales. Rigorous asymptotic results as well as affordable and reliable direct numerical simulations are available to predict the effective large scale behavior of the id...

In the natural history of type 2 diabetes, pancreatic insulin secretion is progressively depleted and metabolic control worsens. Treatment of these patients usually starts with diet and exercise, with subsequent use of oral glucose-lowering drugs, finally ending with insulin therapy to achieve good metabolic control. When there is still endogenous insulin secretion, the combination of insulin a...