SBIR-STTR Award

The objective of this program is to research, formulate, and test high-temperature lubricants, materials, and modified cylinder systems optimized dimensionally for high-temperature operation. The lubricants, related materials, and system design are to operate at a top ring reversal temperature of 410 deg C max and a sump temperature of 175 deg C. The resultant system should provide deposit levels, wear rates, and lubricant durability (viscosity change, soot loading, etc.) similar to well-developed lubricant systems in conventional diesel engines. The development of an effective high-temperature diesel engine could have very favorable results when applied to commercial applications; i.e., sigificant reduction in fuel usage and elimination of initial cost, weight, and maintenance cost associated with water pump, hoses, radiator, etc. Lubrication and cylinder kit life have been identified as major obstacles to the adoption of the adiabatic engine concept

Phase II work focuses on developing an improved high-temperature engine lubricant base stock which will have acceptable vaporization rate and deposits at 875 deg F top ring/liner temperature. Actual lubricating film between the ring face and cylinder liner will be produced by use of a dry-film lubricant additive to the base stock. (Other forms of delivery of dry-film lubricant will be evaluated as part of Phase II also.) The cylinder liner surface character will be modified utilizing a laser integral to the honing process. The objective is to provide micro pockets for retaining residual quantities of dry-film lubricant in the upper ring turn-around area. Work is also planned to evaluate the above stock/dry-film lubricant in conjunction with an advanced liner/ring surface which would form a compatible system capable of operating at 875 deg F.

Keywords:
Lubricants, High-Temperature Lubrication, Cylinder Kit Tribology, High-Temperature Wear, Piston Ring/Liner Coatings