HCCI engine combustion control apparatus and method

Abstract

Compression ignition of a homogeneous air fuel charge in a piston engine is controlled over a substantial range of lean to stoichiometric air fuel ratios by supplying additional heat as required to an open sided hot spot recess in a combustion chamber. A surface electric heater element is controlled in response to sensed engine operating conditions to provide additional heat as required to ignite the charge compressed in the hot spot to initiate combustion that progresses through the open side of the hot spot recess and completes combustion of the cylinder charge in the time interval required for efficient combustion. Matching of the hot spot energy requirements to the cylinder operating conditions of each engine embodiment and the manner of controlling energy transfer must be developed for each engine application to obtain the full benefit of unthrottled combustion of homogenious mixtures over a major portion of an engine operating range.

Dependencies are inferred from the claim text.