The fuel economy of the internal combustion engine becomes progressively critical, especially with the stringent standards set by the government. To meet the government norms such as CAFE (Corporate Fuel Average Economy), different technologies are being explored and implemented in internal combustion engines. Several technologies such as variable oil pump, map controlled PCJ (Piston Cooling Jet), variable or switchable water pump & ball bearing turbocharger etc. This study investigates the effectiveness of implementing map-controlled PCJ implemented for a 1.5-litre 3-cylinder diesel engine.
PCJ’s are major consumers of oil flow and map-controlled PCJ is used by many OEM’s e.g., Ford EcoSport to reduce the oil pump flow. In map-controlled PCJ, the oil to the PCJ is controlled using a solenoid valve. The solenoid valve can be completely variable or ON/OFF type. In our application, the ON/OFF type solenoid value is used to regulate the oil flow to PCJ. Conventionally, the oil to the PCJ is supplied at all operating conditions of the engine, even when the piston temperature is within the material acceptable limit. This adds to the parasitic loss of the internal combustion engine, due to the high friction power consumed by the oil pump to meet the oil flow rate requirement. Using the solenoid-controlled PCJ along with Variable Displacement Oil Pump (VDOP), the flow to the PCJ can be shut down at certain operating conditions such as high speed, and low load conditions. Using the VDOP, the total oil flow rate can be reduced whenever there is no flow to the PCJ, this will help to reduce engine friction load & improve the overall fuel economy.
The objective of the paper is to show the systemic approach, design modifications & challenges involved in the implementation of the map controlled PCJ. The final engine with the map-controlled PCJ along with VDOP is evaluated in the NEDC (New European Driving Cycle) drive cycle to understand the benefits & an overall fuel economy of 1 – 2 % was observed. Results are discussed in detail, which have enabled to take required decision on implementation of Map Controlled PCJ in the specific engine application.