Although the cycle is usually run as an open system (and indeed must be run as such if internal combustion is used), it is conventionally assumed for the purposes of thermodynamic analysis that the exhaust gases are reused in the intake, enabling analysis as a closed system.
尽管循环通常是作为开放系统运行的（并且实际上如果使用内部燃烧必须如此运行），但为了热力学分析的目的，通常假定废气在进气中被重新使用，使得分析成为封闭系统。