The simulated calculation of a fuel injection system is now possible by the use of a computer. However, this calculation does not seem completely satisfactory.
In the conventional methods of calculation, separate calculation equations must be used when a void (the absence of oil) occurs in the injection system. Furthermore, the boundary condition equations applied at both ends of a high-pressure pipe were believed to be inadequate.
In this paper, several improvements are attempted. A quantity that varies from positive to negative value is used as the fundamental variable in the calculations. Also, experiments were made using a test apparatus with a transparent boundary part for both observation and measurement. Moreover, incorporating the fundamental variable, the boundary condition equations were made applicable both to the state of compression and a void condition.
The result of these improvements shows that the simulated calculation procedure is more convenient and widely applicable compared with the procedure used until now.
Those improvements are described through the propagation phenomenon in a high-pressure pipe, which is the basis of an injection system.