The current study focuses on comprehensive fuel spray modeling and its effects on chamber acoustics in combustion dynamics simulations. The fuel spray is modeled using an Eulerian-Lagrangian approach describing the atomizer internal flow, primary atomization, and secondary atomization processes. To anchor the fuel spray model, a series of experiments has been conducted on the fuel atomizer with...

An experimental study was performed to understand the atomization process in the specialized printing method which consists of the high frequency oscillating motion of a needle and a micro air jet. Highly viscous liquids, such as glycerin and acrylic paint were successfully printed with this printing method within the line width of 1 mm. High-speed imaging technique was used to observe the evol...

The flame stability limit, which was involving the critical flow condition, lift off and blow out, could be affected by the burner geometry in the combustion system installation. Consequently a flame holder should be put in, to hold the flame as big as possible on a stable condition. The flame holder itself, is a device to hold the flame, whereas the flame holder could disturb the air and fuel ...

A physics-based, low-order ignition model is used to assess the performance of a kerosene-fueled gas-turbine combustor under high-altitude relight conditions. The in this study based on motion virtual flame particles and their extinction according Karlovitz number criterion, stochastic procedure account for effects spray polydispersity flame’s behavior. large droplets arising from poor fuel ato...

The four processes involved in the flammability of materials are described and related to the various flame retardance mechanisms that may operate. Following this the four practical approaches used in improving flame retardance of materials are described. Each approach is illustrated with a number of typical examples of flame retardants or synthetic procedures used. This overview of flammabilit...

Extinction limits and flame bifurcation of lean premixed dimethyl ether-air flames are investigated numerically using the counterflow flame with a reduced chemistry. Emphasis is paid to the combined effect of radiation and flame stretch on the extinction and flammability limits. A method based on the reaction front is presented to predict the Markstein length. The predicted positive Markstein l...

The droplet and flame chemiluminescence dynamics as well their coupling during atomization events of graphene oxide doped diesel are investigated experimentally. tested doping concentrations 0, 0.001, 0.005, 0.01, 0.02% by weight. To minimize heat transfer between the its suspension mechanism, small diameter fibers used for suspension. Separate shadowgraphy OH* measurements performed at 4000 Hz...

Semilocal density functionals for the exchange-correlation energy are needed for large electronic systems. The Tao-Perdew-Staroverov-Scuseria (TPSS) meta-generalized gradient approximation (meta-GGA) is semilocal and usefully accurate, but predicts too-long lattice constants. Recent "GGA's for solids" yield good lattice constants but poor atomization energies of molecules. We show that the cons...

The accuracy and effectiveness of various kinetic-energy functionals in providing total noninteracting kinetic energies, atomization kinetic energies, and equilibrium properties is evaluated. Employing converged Kohn-Sham densities, we assess various kinetic-energy functionals in a non-self-consistent manner. It is found that the gradient expansion, the Pearson-Gordon local truncation scheme, a...

Metal powders prepared by laminar flow gas atomization have the advantages of small particle size and narrow distribution. At present, research on mainly focuses influence process parameters powder characteristics, but mechanism is still not clear. In this work, flow, primary secondary breakup mechanism, morphology are systematically investigated through numerical simulation experimental analys...