Dynamic Analysis of Fluid Flowing Through Micro Porous Filters Using Bondgraph Approach

Delivery of optimized fuel injection pressure to combustion chamber of an engine assembly leads to optimum torque and horsepower. Contaminant free supply of fuel without compromising on volume flow rate is the most important design requirement. Incorporation of very fine fuel filters having less than 10 micron rating reduces volume flow rate at the injection nozzles whereas fuel filter with larger pore size stabilize the injection pressure but may result into failure of fuel injection pump assembly due to scuffing produced by the fuel contaminant between the plunger and sleeve of hydraulic head of fuel injection pump. The fuel flows from fuel tank through low-pressure injection line, primary and secondary fuel filters, fuel transfer pump, fuel injection pump, and high-pressure injection line and injector nozzles. Modeling and simulation of volume flow rate vis-a`-vis fuel injection pressure together with micro-porous fuel filter poses a formidable challenge. Bondgraph method (BGM) is ideally suited for the modeling and simulation of such a multi-domain dynamic system. The aim of this research is to apply BGM to model and simulate the optimized fuel injection pressure and analysis of filters with different micro-porosity and their effect on volume flow rate. Fuel filter porosity, inlet and outlet pressures of transfer pump, fuel injection pump and low/high pressure injection line pressure have been determined experimentally. These experimentally determined parameters are then used as input in our Bondgraph model for the dynamic analysis of fuel injection pressure incorporating micro-porous filters.