Piezo-actuated common rail injector structure and efficient design

Abstract

Piezo-actuated common rail injectors are often utilized in today’s automobile engines’ fuel systems. This high-tech instrument decreases fuel consumption, thereby harmful exhaust emissions are also lowered especially in diesel ignition engines. Owing to ultra-high pressure in piezo-injection systems, fuel droplets are scaled down into a smaller particle form and thus provided more efficient combustion. Pulverized fuel droplets are evaporated and oxidized in a very short time and they provide exact combustion inside the combustion chamber. In this study, numerical simulation of a piezo-actuated common rail injector fluid-mechanical model with detail is demonstrated. The hydraulic and mechanical component interaction is modeled through the fluid-mechanical components. Thus, the piezo injector dynamics are predicted based on the geometry and the physical quantities describing the equipment. Input voltage in the entrance is used to describe the piezo actuator force for piezo-electric material. In model, fuel flows from the common rail to a tee that separates the flow into two paths: fuel gallery and valve with the inlet orifice. Using this detailed model, behavior of the piezo injector, effects of the injector parameters on the fuel flow were investigated numerically and results were represented.