The environment has recently led to very severe regulations on fuel consumption and exhaust emissions. I propose a scheme to minimize rate of fuel consumption for a direct fuel injection engine used by combination with a continuously variable transmission. Target values for the engine and the transmission which minimizes fuel consumption ensuring driving performance is calculated based on the n...

Pollutant emissions from diesel engines are significantly affected by fuel injection strategies that could reduce NOx and Soot emissions. For the first time and in this study, numerical simulations were performed to consider the influences of changing the injection duration in each pulse of the double injection strategies on in-cylinder parameters and pollutant emissions. Results confirmed that...

In this computational research, the separate and simultaneous impacts of diesel direct injection timing, fuel spraying cone angle, and hydrogen gas addition on combustion characteristics, output emissions, and performance in a single-cylinder direct injection diesel engine was studied. In order to conduct the simulations, valid and reliable models for combustion, break-up, and for turbulence wa...

One of the important problems in reducing pollutant emission from diesel engines is trade-off between soot and NOx. Split injection is one of the most powerful tools that decrease soot and NOx emissions simultaneously. At the present work, the effect of split injection on the combustion process and emissions of a direct-injection diesel engine under full-load conditions is investigated by the c...

in the present work, the simultaneous effects of fuel injection rate and injection of air jet into the combustion chamber on exhaust emissions, combustion process and performance parameters in a direct injection diesel engine were investigated. in order to create an air jet, a design was presented in which a secondary chamber (air cell) was created inside the cylinder and was joined to the main...

This paper presents experimental test results of a new compressed natural gas direct injection (CNG-DI) engine that has been developed from modification of a multi cylinder gasoline port injection (PI) engine. The major modifications done are (1) the injection system has been modified to gas direct injection using new high pressure gas injectors, (2) compression ratio has been changed from 10 t...

Abbreviations: aBDC, after bottomdead center; aTDC, aft bottomdead center; bTDC, before top dead center; CA50, cra fraction reaches to 50%; CI, compression ignition; COVime indicated mean effective pressure; DI, direct injection; DIS DOI, duration of injection (first DOI1, second DOI2); EGR, homogenous charge compression ignition; IMEP, indicat injection ratio; MPRR, maximum pressure rise rate;...

In this work, result of experimental investigation on interaction of fuel spray generated by a swirled type injector, with air motion in a prototype cylinder are presented. Experiments were carried out by planar imaging and particle image velocimetry (PIV) techniques in order to provide information about the spray structure evolution and instantaneous velocity distribution of air motion and ...

Propane combustion in a trapped vortex combustor (TVC) is characterized via large eddy simulation coupled with filtered mass density function. A computational algorithm based on high order finite difference (FD) schemes, is employed to solve the Eulerian filtered compressible Navier-Stokes equations. In contrast, a Lagrangian Monte-Carlo solver based on the filtered mass density function is inv...