Rotating Liner Engine: Improving Efficiency of Heavy Duty Diesels by Significant Friction Reduction, and Extending The Life of Heavy Duty Engines.

The ultimate goal of the project is to demonstrate that the rotating liner engine (RLE) can increase fuel efficiency in heavy duty vehicles by about 3.5-4% at full load, about 25% at idle, and about 10% for an average duty cycle, can reduce CO2, NOx and PM and reduce engine wear. Design already completed. The face seal is the only technical challenge of the concept, and the main design features performed well in the light duty alpha version. In this Phase I project, the beta prototype single cylinder engine will be constructed, with the main objective to demonstrate the re-optimized face seal under diesel-level combustion pressures. However, preliminary measurements on friction reduction will be possible. Phase II will generate a map of friction reduction as a function of engine speed, load, and hours of operation. This can then be extrapolated to a full size engine and different driving cycles, and prove payback of about 6 months for fleet managers who purchase heavy duty engines with RLEs. In addition to new engines, due to the proposed semi- external liner driving mechanism, existing engines in need of overhaul can be converted. The RLE concept (winner of 2005 Max Bentele award for engine innovation past the proof of concept) is not a radical technology, but simply an innovative combination of well established technologies, such as face seals, and Sleeve valve Engines, both of which are well proven applications in the field of mechanical engineering, but applied in different industries and time domains. Face seal technology is known to be capable of containing over 5,000 psi in a rotating dynamic seal without wear, while the Sleeve Valve technology has proven the lubrication benefits of a rotating liner on a reciprocating piston under high BMEP operation. Most conventional work in the area of reducing piston assembly friction has revolved around improved piston ring profiles and liner honing/coating/surface texture. Unfortunately, these efforts offer relatively small friction reductions and have little value in heavy-duty engines. Literature on wear rates in diesels indicates that wear during the initial 500-1,000 hours is deep enough that it eliminates all such optimizations and surface textures, while the typical life of such engines in commercial operation is of the order of 20,000 hours. The RLE, even initially more expensive than coatings and ring profile optimization, offers a friction reduction mechanism that almost completely eliminates the boundary/mixed regime friction and associated wear from the piston assembly, and will persist throughout the longer life of the engine. The fuel economy benefit alone is expected to pay back the increased engine cost within the 6 months of operation for a Class 8 truck. Commercial Applications and other Benefits Reduce U.S. demand for petroleum, lower carbon emissions and decrease energy costs by implementing the RLE as a standard feature in heavy duty engines Prove to fleet managers that the RLE increases fuel efficiency, reduces emissions, reduces engine wear, and will not adversely affect performance of their engines; and prove to OEMs that they can generate acceptable gross margins by offering RLEs.