Showing 3 results for Cfd
M. H. Shojaeefard, I. Sohrabiasl, E. Sarshari,
Volume 1, Issue 2 (6-2011)
Abstract
Intake system design as well as inlet ports and valves configuration is of paramount importance in the optimal performance of internal combustion engines. In the present study, the effect of inlet ports design is investigated on OM-457LA diesel engine by using a CFD analysis and the AVL-Fire code as well. A thermodynamic model of the whole engine equipped with a turbocharger and an intercooler is used to obtain the initial and boundary conditions of the inlet and outlet ports of the engine cylinder which are necessary for performing the three dimensional CFD analysis. The intake stroke as well as the compression and power strokes are included in this three dimensional CFD model. As a mean of validation the performance of the engine model with the base configuration of the inlet ports is compared to the experimental data. Two new alternative configurations for the inlet ports are then investigated with respect to the turbulence levels of the in-cylinder flow and the combustion characteristics as well. Finally it is demonstrated that applying the new configurations results in circa 75% reduction in nitric oxide formation besides increase of 32% in the in-cylinder flow swirl.
B. Jafari, D. Domiri Ganji,
Volume 3, Issue 2 (6-2013)
Abstract
Air pollution is one of the major issues about the diesel engines in todays' world. It is a special concern in
those areas that have difficulty meeting health-based outdoor air quality standards. Natural gas has low
emission and resource abundance and also conventional compression ignition engine can be easily
converted to a dual fuel mode to use natural gas as main fuel and diesel as pilot injection. The main object
of this work is to investigate the effect of number of injector nozzle hole on the combustion and exhaust
emission in a gas engine ignited with diesel fuel. We use one and three-dimensional simulation in parallel
way in order to analyze the performance and combustion process of a dual fuel engine. The experimental
results have also reported and compared with the simulated data.
Sina Hassanzadeh Saraei, Shahram Khalilarya, Samad Jafarmadar, Saeed Takhtfirouzeh, Hadi Taghavifar,
Volume 8, Issue 4 (12-2018)
Abstract
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 double injection strategies could influence the in-cylinder temperature, which leads to a reduction in NOx and soot emissions. Additionally, it is seen that decreasing the injection duration could increase the in-cylinder peak pressure and temperature. It could also reduce the soot emission owing to the better fuel atomization. Moreover, RATE+0.5CA case, which injection duration for each pulse increases 0.5 CA, was selected to be the optimum case in reduction of pollutant emissions.
