Orbital engine

The Sarich orbital engine is a type of internal combustion engine, featuring rotary rather than reciprocating motion of its internal parts. It differs from the conceptually similar Wankel engine by using a shaped rotor that rolls around the interior of the engine, rather than having a trilobular rotor that spins "in place".



Overview

The advantage is that there is no high-speed contact area with the engine walls, unlike in the Wankel where edge wear is an ongoing engineering problem. However, the combustion chambers are divided by blades which do have contact with both the walls and rotor, and are said to have been difficult to seal due to the perpendicular intersection with the moving empellor.

The orbital engine was invented in 1972 by Ralph Sarich, an engineer from Perth, Australia, who worked on the concept for years without ever producing a production engine. A prototype was demonstrated, running on the bench with no load.


Technical problems

The Sarich Orbital engine has a number of fundamental, unsolved problems that have helped keep it from becoming a practical engine. Amongst other things, there are key components that cannot be cooled, and other components that cannot be easily lubricated.


Political problems?

A conspiracy theory known to almost all mechanically-inclined Australians holds that the patent for the Sarich Orbital engine was exclusively licensed and then suppressed by Ford, perhaps in order to prevent a drop in oil prices, or simply to maintain the value of existing manufacturing facilities, should the highly-efficient engine displace conventional piston engines.

More widely, the case is seen as a defining example of a syndrome of 'good invention, poor development' felt by many nations, with an unusually high number of good inventions becoming successful products only once they have shifted off-shore, and with economic returns on the inventions not being returned to the nation's economy.