Catalytic combustion engines

Abstract

A reciprocating-piston internal combustion engine with catalytic combustion has associated with the or each cylinder a swirl-promoting precombustion chamber in the cylinder head connected to the space in the cylinder above the piston by an inclined transfer passage formed in a 'hot plug' inserted in a well in the head. A catalytic screen preferably comprising a platinum gauze extends across the top of the hot plug with its peripheral margin wrapped around the hot plug and trapped between the plug and the cylinder head. The plug has an open-topped recess formed in its upper side, into which recess the transfer passage leads, the recess constituting the lower part of the precombustion chamber and the catalytic screen separating this recess from the remainder of the interior of the precombustion chamber above the screen. An injector injects liquid fuel into the precombustion chamber above and parallel to the catalytic screen. The engine has a very much lower compression ratio than a normal compression-ignition engine, for example in the range 11:1 to 15:1, and can operate on gasoline, methanol or diesel fuel.