Non-Linear Dynamic Analysis of Fluid-Structure Interaction in High Pressure Injection System Using Bond Graph Approach

A rotary diesel fuel injection pump (RDFIP) takes drive from the engine assembly of an automobile engine. The critical part of RDFIP is plunger, which reciprocates as well as rotates in the plunger sleeve. The main function of plunger is to inject high pressure atomized fuel to the engine cylinder. Diesel fuel acts as a lubricant between the plunger and sleeve. The wear between the plunger and plunger sleeve causes considerable reduction in injection pressure and the quantity of fuel to the combustion chamber, which ultimately leads to an inefficiency of the engine assembly. The modeling and simulation of such a multi-domain dynamic system poses a formidable challenge. The conventional techniques are simple inadequate for the modeling and simulation of multi-domain dynamic systems. Bond Graph Method (BGM) is ideally suited for the modeling and simulation of multi-domain dynamic systems. The aim of this research is to apply BGM to model and simulate an RDFIP system, fuel feed pump, plunger motion, injection pressure and quantity of fuel flow. The parameters such as specific heat of diesel fuel, diesel fuel density, fuel inlet temperature, fuel outlet temperature and radial clearance have been experimentally evaluated. These experimentally determined parameters are then used as input in our computer program to lend more confidence to our predicted results. The predicted results based on BGM are validated by comparison with results based on other techniques