Effect of port injection CNG engine using injector nozzle multi holes on air-fuel mixing in combustion chamber

Compressed natural gas (CNG) is the most favorite for fossil fuel substitution. There are four methods to inject the CNG into the engine cylinder, such as gas mixer / carburetor injection, single point injection, sequential injection and direct injection. In sequential port injection CNG engines, gas fuel is injected by fuel nozzle injector via intake port into combustion chamber. To improve the perfect of mixing process of CNG fuel and air in combustion chamber is by arranging of injector nozzle holes number. The objectives this paper is to design and investigate the injector nozzle multi holes and the effect on air-fuel mixing in combustion chamber of sequential port injection CNG engine based on variation intake valve lift using CosmosFlow simulation. The simulation of injected gas fuel and intake air mixing in the combustion camber of new injector nozzle multi holes geometries effect is conducted in 1.78mm, 3.55mm, 5.33mm and 7.10 mm intake valve lift and in 1000 rpm engine speed. The results are shown, that the 4 holes injector nozzle is has the best in air-fuel mixing. In the best trend air-fuel mixing results, the injected gas fuel and intake air has been mixed spread evenly in combustion chamber.