Combustion chamber`s nominal structural characteristic e.g. cylinder head`s shape, determining method for e.g. four stroke diesel engine, involves varying piston-cylinder head distance at top dead center of piston by variation system

摘要

The method involves forming a combustion chamber by a cylinder (1), a cylinder head (2) and a piston (3) mounted slidingly in the cylinder. A geometric compression ratio variation system is adapted to vary the piston-cylinder head distance at the top dead center of the piston between maximum and minimum piston-cylinder head distances. The determination of the structural nominal characteristics of the chamber is carried out with a piston-cylinder head distance which is nearer or equal to the maximum piston-cylinder head distance corresponding to the ratio which is lesser than or equal to 16. An independent claim is also included for a direct injection engine comprising a combustion chamber.