About this model & sources
Conceptual aviation engine models for exploring architecture and energy flow. Stage counts, blade shapes, dimensions and power response are simplified. Motion is slowed; particles do not measure mass flow, temperature or thrust. These are not replicas of particular manufacturers’ engines.
The turbofan has two direct-drive spools. The turbojet has one compressor–turbine spool. The turboprop and turboshaft use a separate free power turbine and simplified reduction gearbox. All models use a straight-through core for comparison; actual engine layouts vary.
Sources: NASA — Turbofans, NASA — Turbojets, and NASA — Turboprops and turboshafts.