hfi (hot fuel injection) injection for diesel engines

摘要

The injection in the case of diesel engines, it has been found in the last few years in the direction of the increasingly higher injection pressures have been developed. The effort necessary for this purpose is immensely and a further development in this direction is not conducive to. The present invention is a further development of the application no. 102013011670.8 from the 12.07.2013, in which the heating of the fuel in the injection valve, optionally by means of microwaves are injected or by means of supercap capacitors is effected via a resistor. A new design of the heating chamber in the injection valve now allows for the direct heating by means of battery voltage. It is both a variable volume chamber as well as with a fixed volume possible.Variable heating chamber for the fuel by means of a movable piston, which the volume of the chamber between the minimum - and maximum - injection quantity controls. The round cross section of the chamber is kept fairly large, so that the piston travel, the height of the chamber, has to travel only a small path. The movement of the piston by means of a piezo stack can be carried out and a transmission ratio. In this way, it is possible to achieve a very precise.The injection pressure is by means of an electrical heating of the metered fuel quantity produced in the heating chamber.The energy pulse, by means of the board operation voltage across a tungsten wire loop in the heating chamber are fed in the injector.The energy pulse is dimensioned in such a way that the metered quantity of fuel is heated to 400 kelvin.The thus attendant expansion of the volume of about 33% in the closed container can take place not. The result is an extreme increase in pressure. In the case of opening of the injection valve, this pressure builds up abruptly and the superheated fuel evaporates in the combustion chamber. In this case, it is withdrawn from the combustion air approximately 0,27 j evaporation energy per mm3 fuel. The mixing of the vaporized fuel with the compressed air in the combustion chamber ignites the air - gas - mixture with a minimum ignition delay and provides for the case of an extreme increase in pressure in the combustion chamber.