Development of a Heavy-Duty Engine Lubrication System for Low Parasitic Loss.
2022-01-0763
03/29/2022
- Event
- Content
- As one element of the US Department of energy sponsored SuperTruck-II program, Daimler evolved a unique engine lubrication circuit having the objective of minimizing parasitic energy loss. An auxiliary oil circuit supplied by a 48-volt electric oil pump was created separate from the main circuit specifically to serve the piston cooling jets and to provide a per-lube function for the engine. The reduced flow demand now placed on the main mechanically driven pump allowed it to be significantly downsized, and a close-coupled electronic pressure regulating valve minimized recirculation pressure loss. Piston cooling jet flow from the auxiliary circuit could be regulated to closely match real-time piston thermal loading by controlling pump speed, and could be inhibited altogether below a given engine load threshold. A 3-port solenoid valve in the auxiliary circuit was arranged to interconnect this circuit with the main engine circuit and thereby enable the pre-lube feature and provide make-up flow to the main circuit if required. A control strategy was developed to fully exploit the features of the system, and a concept for engine health prognostics was proposed.
- Citation
- Bashir, M., and Musselman, S., "Development of a Heavy-Duty Engine Lubrication System for Low Parasitic Loss.," SAE Technical Paper 2022-01-0763, 2022, .