Split-cycle engines have been around for some time but until now have never matched the fuel efficiency of traditional internal combustion engines. That is about to change, with the latest split-cycle engines from the Scuderi Group offering greater fuel efficiency and up to 80 percent reduction in NOx emissions and 50 percent reduction in CO2.
Split-cycle engines feature paired cylinders, so a four-cylinder engine has two sets of paired cylinders working together, with a crossover passage linking the two cylinders in each pair to each other. The four strokes of the engine are split into two groups, with the left cylinder handling intake and compression and the second handling combustion and exhaust. The Scuderi™ Air-Hybrid design adds an air storage tank and controls that allow it to recapture and store the energy lost as the engine operates.
The new design solves some of the problems that have hampered previous split-cycle designs. The low volume breathing problem is solved by outward-opening pneumatic valves and a reduction in the clearance between the piston and cylinder head to under 1 mm, which means virtually 100 percent of the compressed air is pushed out of the cylinder.