Dual fuel system for IC engine - has heat exchanger on exhaust pipe to preheat combustion air or fuel mixt. entering inlet manifold

摘要

A heat exchanger (1) is placed round the exhaust pipe (5) of the engine as close as practicable to the cylinder block (39). Heat is transferred from the exhaust to air or a mixture of gas and air flowing through the exchanger. When the engine operates on petrol the combustion air is taken through the heat exchanger before passing to the carburettor. When the engine operates on gas the gas air mixture flows through the exchanger before reaching the inlet manifold (3). Exhaust from a point (4) downstream of the exchanger is also recycled (51) to the suction manifold to improve combustion.