Airless engine with gas and water recycling

Abstract

An internal-combustion engine receives no air from outside atmosphere. Instead, combustion gas expelled from the engine is cooled and recycled back into the engine. That gas contains no nitrogen and consists mostly of carbon dioxide and water vapor. Oxygen and fuel are added to the recycled gas, and the resulting mixture is used to perform an internal-combustion cycle. Cooling that gas condenses its water vapor, and liquid water is separated from the gas. That water is used for injection into the recycled gas at a later time. A small amount of the expelled combustion gas is discharged into outside environment, and the rest is recycled. Water too is recycled back into the engine, and whatever is lost to outside environment is replaced by reclaiming water produced in combustion. No additional supply of water is needed. Since no nitrogen is present, no nitrogen oxides are produced. The amount of other harmful exhaust emissions is greatly reduced too, since most of them are recycled back into the engine. Water evaporation in the cylinders greatly improves fuel economy. The engine is inherently supercharged with combustion-gas pressure, and no turbocharger is needed. Since the combustion gas is heavier than air, the engine can be substantially smaller than a conventional engine of equal power. A smaller engine has less friction.