Robust Engineering Methodology for Pulsation Noise Reduction in Gasoline Vehicles 2013-01-2740
Nowadays much greater emphasis is given on improving the NVH Performance of an automobile due to global move of customer satisfaction. Noise is an irritant to a valued customer - customer expects value for money in all perspective. There are many sources for noise generation in a vehicle. Noise due to pulsating fuel flow is one of the major causes. The pressure pulsation from the fuel supply system (generated by the sudden opening & closing of the injectors result in pulses inside rail, Low Pressure or High Pressure pump pulses, sudden cross section changes in flow path, etc) can cause an undesirable noise which may propagate as fluid or structure borne noise in to the cabin room, therefore in a conventional engine, a pulsation damper is usually mounted on the fuel rail to diminish the undesirable noise. However, the pulsation dampers are quite expensive. Therefore, several studies have focused on reducing fuel pressure pulsation by various methodologies.
Noise reduction can happen,
At source (Low Pressure Pump / High Pressure Pump / Fuel Injector / Fuel Rail),
In the propagation path (Through Clamps, Body),
At receiver end (Inside Cabin).
In this paper, the design process of a fuel system using Robust Engineering methodology is presented. Through research, simulation & experimental study, few control factors were investigated in determining the optimal design of fuel system which produces the lowest feasible levels of fuel pressure pulsations & noise. Noise control factors which were studied include Fuel Rail design, Fuel parameters, Engine RPM, Fuel Pipes / Hoses design & Fuel Injection parameters, etc.
Thus by optimizing the control factors such as Fuel Rail design parameters as said above, it is possible to reduce the fuel pressure pulsation & noise even in absence of a pulsation damper.