en موتور احتراق داخلی Internal Combustion Engines (ICE, ...) پژوهشي Research 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. Dual fuel engine, Combustion, Emission, CFD, Numerical simulation, Number of nozzle hole 412 423 http://ase.iust.ac.ir/browse.php?a_code=A-10-63-41&slc_lang=en&sid=1 Jafari 18003194753284600848 18003194753284600848 Yes Domiri Ganji 18003194753284600849 18003194753284600849 No