Investigation Of Variable Displacement Oil Pump and Its Influence on Fuel Economy for a 1.5 L, 3 Cylinder Diesel Engine

The Introduction of Corporate Average Fuel Economy (henceforth will be addressed as CAFE) regulations demand suitable technological upgrades to meet the significant increase in targets of vehicle fleet fuel economy. Engine Downsizing and Friction Reduction measures help in getting one step closer to the target. In a Conventional Oil Pump, the pump discharge flow and pressure are a direct function of operating speed. There is no control over lubricant flow which results in increased power and fuel consumption due to its unnecessary pumping characteristics irrespective of the actual engine demand. This paper discusses the introduction of a variable displacement oil pump (henceforth will be addressed as VDOP) that was adapted to a 1.5-liter 3 Cylinder Diesel Engine. This approach helps the system to reduce parasitic losses as the oil flow is regulated based on the mechanical needs of the engine. The flow is regulated with help of a solenoid valve which receives input from the ECU. The engine Oil Pump has a major role in enabling the transfer of lubricant to all moving engine components. The demand majorly depends on engine performance characteristics, bearing clearances, operating temperatures, and wear behavior of engine components. The paper explains the boundary conditions for VDOP design packaging, challenges in system adaptation, impact on engine lubrication circuit, performance, and friction reduction benefit.