抄録
Instead of the traditional theoretical thermal efficiency in a combustion chamber [CC], the improved energy conversion efficiencies have been adopted in a CC and a whole engine [WE]. They are named in "the theoretical energy conversion efficiency in a CC (η_EN= [W_<th>/E_<su>] _<cc>)", "the provisional-net energy conversion efficiency in a WE(η_<PN> = [W_<PN>/E_<su>]_<WE>)" and "the estimated net (brake) thermal efficiency (η_<e(ES)>/E_<SU>]_<WE>)". As some points for the improvement, there are the distinctions of the phenomena in a combustion chamber, the adoption of the total energy supplied instead of heat supplied, the adoption of the energy quantity basing the lowest state of a cycle and so on. As a result, some outcomes of the improvement have been able to be gotten. Especially, as a result of analyzing of the Sabathe-type engine, both targets of maximum power and maximum economy have been demonstrated.
