Opposed Piston 2-Stroke Engine
From Open Source Ecology
Design Considerations
- Potential for Hydrogen operation - [1]
- In July 2021, Cummins was awarded an $87M contract by the United States Army to complete the development of the Advanced Combat Engine (ACE), a modular and scalable diesel engine solution that uses opposed-piston technology. [2]
- Typical 4 stroke fuel-specific oil consumption is .1 percent, and opposed piston engines need to match this to be competitive [3]
- Oil scraper rings are used on outboard side in opposed-piston engines [4]
- Texturing of bore is i.portant. plateaus work better. Laser etch adds more retention. See above link.
OSE Proposal for Hydrogen Hydraulic Engine
- Piston-ported exhaust, air bearing-piston, with overhead valve with direct hydraulic pumping on the opposite side, with pilot-flow cylinder return. May need Hydraulic Accumulator for smoothing.
- Lubrication is via hydraulic fluid, which addresses the lubrication and oil-burn issue of regular 2-strokes, as no oil is used in the fuel
Free-Piston