Internal combustion micro-chambers and micro-engines

Technological progress caused miniaturization of internal-combustion engines. They found application in many areas. The acquaintance of the ignition and combustion processes in the small volumes, the solution of the problem of piston movement under the influence of a pulse combustion in chambers, the choice of materials and problems related with the mixtures and exhaust creation, all these issues require a exact acquaintance for the purpose of optimization of the micro engine performance. In the paper, some issues are talked over on the base of investigations performed on the small volume chambers in single compression machines and in the shaftless two-cycle engine. Researched was the influence of the micro chamber size and of the area/volume ratio value on the processes of combustion occurring in the very small volumes and with the large values of area/volume ratio. Together with raise of the area/volume ratio, the value of the combustion pressure impulse becomes lower. The influence of the chamber material type on the combustion processes was defined, both in the single compression machine as in the micro engine. The existence of micro chamber size influence on the combustion limits of the fuel/air mixtures was designated. It has been determined that the range of the combustion limit is decreased with diminishing of the combustion chamber diameter, at the same time these changes are not the function of the area/volume ratio value changes. The maximum values of the combustion pressure appeared when chamber was supplied with stoichiometric mixture, irrespective of the chamber dimensions.