Ceramic Rotary Engine FUEL ECONOMY OF THE CERAMIC ENGINE
Until now, rotary engines have been notoriously uneconomical with fuel. A conventional metal rotary engine will typically return a specific fuel consumption in the region of 0.55 l/kW.hr whilst a modern diesel engine will be in the region of 0.32 l/kW.hr. This means that a small family diesel engined car that is returning 60 mpg on a motorway journey will only return about 35 mpg if powered by a conventional rotary petrol engine.

The ceramic rotary engine will be a direct injection multi-fuel engine operating on a diesel cycle. The efficiency of this engine will be improved dramatically compared with a metal rotary engine because of a significantly improved combustion process and a large reduction in waste heat rejection.

The properties of the ceramic material allows the internal surfaces of the rotor housing wall, rotor flanks and end plates to operate at very high temperatures. This ensures rapid and complete combustion of the fuel at an early stage in the cycle giving rise to peak cylinder pressures at a time when maximum torque can be generated by the rotor. This factor alone will make the ceramic engine comparable with conventional diesel engines.

In addition, very little heat is transmitted from the combustion chamber through the engine casing to the surroundings. A normal metal engine (reciprocating or rotary) may throw away 30% of the heat energy extracted from the fuel during combustion as waste heat. Normally this finishes up heating the surrounding atmosphere via the radiator. The ceramic rotary engine has no radiator and is designed to cut this loss by at least 90%.

The 'Second International Symposium for Ceramic Materials and Components for Engines' has conservatively estimated that a 60% saving in the heat lost to the engine's structure will result in a 12% saving in fuel. This means that the small family car powered by a ceramic rotary engine should return at least 70 mpg on that same journey. The global effect of such a reduced fuel consumption is massive. In the USA, for example, a 10% saving on daily gasoline consumption could be equivalent to 50 million US gallons. If based on $2 per gallon, this translates into $100M per day.