Genuine New Cat Perkins Diesel Fuel Injector 2645A743 321-0990 10r-7668 Compatible with Perkins Pj Engine

The effect of nozzle diameter, injection pressure and ambient temperature on spray characteristics in diesel engine (part 3)

3. Result and discussion

This analysis used two different diameters which is 0.20 mm and 0.12 mm. This simulation using several different ambient temperatures on 500 K and 700 K for every injection pressure simulate with 40 MPa, 70 MPa and 140 MPa. The objective for this simulation is to investigate the different form of spray characteristic that influence by the nozzle diameter, ambient temperature and injection pressure of diesel engine. The analysis of spray characteristic of this simulation is more focus to the droplet diameter, penetration length and breakup length that influence from the parameter use. Grid sensitivity was tested on the model with different grid sizes. The grid size divided into three levels which are coarse, medium and fine grids. Table 2 indicates the number of elements and nodes for each group of different grid sizes.

Besides, the number of elements is ranging from 24997 to 114555 elements. The number of elements is obviously directly proportional to the numbers of nodes by ascending the level of grid sizes from coarse to fine with also level of smoothing from low to high.

Droplet diameter of the spray was being Figure 6 shows that at 40 MPa droplet diameter at 0.20 mm and 500 K parameter show more droplet size colour red represent to a big size droplet compared to the 0.12 mm 700 K. The droplet distribution size of 0.12 mm and 0.2 mm are shown in the Figure 7 and 8. As illustrated in the graphs, they show that the pattern of the distribution size of the droplet is parallel to each other. The higher of ambient temperature and injection pressure give the smaller droplet diameter.

The result describe that slightly fuel injected in the chamber can cause a lower combustion. At the same time droplet diameter depend on the aerodynamic drag in the chamber it can affect the droplet diameter performed smaller when the air collision with the fuel.