Diesel Injector Fuel Injector 2645A749 2645A735 320-0690 292-3790 306-9390 for CAT C6.6

At present, there have been a lot of researches on cold spray, but in GDI engine, for flash spray applied on porous injector, most of the current researches analyze the characteristics of flash spray itself. In addition to the thermodynamic state of the spray itself, there are few researches on the influencing factors of spray collapse caused by flash boiling spray applied to porous fuel injectors.

In this paper, the 3D numerical simulation software Converge is used to simulate the influence of different conditions on the spray collapse phenomenon of porous fuel injector in detail, and the specific conclusions are as follows:

1. For porous fuel injectors, the collapse degree of spray will become severe with the increase of temperature. This is because the strong flash-boiling phenomenon makes a single oil bundle produce a low pressure area due to the strong airflow movement, and the increase of spray cone Angle oil makes the low pressure area formed by each oil bundle form a large low pressure area. Each oil bundle converges to the center under the action of pressure difference, and serious interference occurs between oil bundles. Spray collapse will cause the oil beam to converge, increasing the spray penetration.

2. Proper increase of ambient pressure will increase the pressure difference inside and outside the spray, thus aggravating the spray collapse phenomenon; The phenomenon of spray collapse does not change significantly with the increase of ambient temperature, but it will reduce the spray heat dissipation and improve the evaporation rate of spray droplets.

3. Improving the distance between spray oil bunches by changing the number of spray holes, the direction of the oil bunches and the distance between the spray holes can effectively weaken the phenomenon that the low pressure area produced by each oil bundle is connected together, thus reducing the degree of spray collapse and improving the spray effect.