Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. The MIT Faculty has made this article openly available. Please share how this access benefits you. Your story matters. [1] We have studied ice formation at temperatures relevant to homogeneous and heterogeneous ice nucleation, as well...

A detailed chemistry-based CFD model was developed to simulate the diesel spray combustion and emission process. A reaction mechanism of n-heptane is coupled with a reduced NOx mechanism to simulate diesel fuel oxidation and NOx formation. The soot emission process is simulated by a phenomenological soot model that uses a competing formation and oxidation rate formulation. The model is applied ...

This paper describes the modifications and evolution of a thermal pulse combustionmodel for predicting the combustion oscillations of an aerovalved 250 kW pulse combustorincorporating a soot formation-combustion model. Validation of the model is carried out from theexperimental data of an aerovalved Helmholtz type pulse combustor, where a sinusoidal air inlet massflow coupled with pressure osci...

The formation of soot particles in combustion depends on several factors that include: pressure, temperature, fuel chemical structure and extent of premixing. An improved version of the thermophoretic particle densitometry (TPD) method, has been used in this study for quantitative and qualitative characterization of soot particles generated in laminar partially-premixed co-flow flames having di...

Optical techniques, such as the light extinction and scattering as well as the laser-induced incandescence and the spectral soot emission, have been used routinely to measure soot concentrations in atmospheric flames. Laser-induced incandescence and light scattering have been proven to measure the primary soot particle size as well in atmospheric flames; however, using these two techniques for ...

An experimental study of the interaction of a planar diffusion flame with a line vortex is presented. A planar diffusion flame is established between two coflowing, equal velocity streams of acetylene diluted with nitrogen and air. A line vortex is generated on demand by momentarily pulsing one of the flow streams by way of electromagnetic actuation of a piston in the flow apparatus. The flame–...

Laminar, sooting, coflow diffusion flames at atmospheric pressure have been studied experimentally and theoretically as a function of fuel dilution by inert nitrogen. The flames have been investigated with laser diagnostics. Laser extinction has been used to calibrate the experimental soot volume fractions and an improved gating method has been implemented in the laser-induced incandescence (LI...

main purpose of current study is development of a new multi zone model for direct injection diesel engines. zone configuration is based on conical shape of spray. siebers’s correlation is used for spray cone angle calculation. experimental data are used for calculation of fuel inlet mass flow rate. fuel diffusion in different zones is calculated using fick’s law. a chemical kinetics mechanism c...

Major pollutants emission from Direct-Injection (D.I) diesel engines are predicted by means of a mathematical model. In order to construct such a model, an integral Multi-Zone Combustion Model (MZCM) is formulated, which basically consists of jet mixing and combustion submodels. In MZCM, variation of injection pressure is considered. Also time period of ignition delay is predicted by considerin...