Closed cycle air engines

Open Cycle Closed cycle Description
Direct heating These are air engines have an open furnace that heats the working fluid externally. This means that the working fluid is heated indirectly and not directly.
The engine works on an closed cycle. The same air is used again and again, heated up to do work, and then cooled down before starting the cycle again; the air is never rejected into the atmosphere.

Examples of closed cycle hot air engines:
- The Stirling engine,
- The Rider hot air engine,
- The Lehmann air expansion engine.
Indirect heating Closed cycle engine

Engine characteristics

Inventors of closed cycle air engines

Year Inventor Country Engine page
1816 Stirling Scotland Stirling engine
1827 Stirling Scotland Stirling engine
1827 Parkinson & Crosley England Parkinson & Crosley Motive Engine
1833 Ericsson Sweden / England Ericsson caloric engine
1838 Franchot France Le moteur à air chaud de Franchot
1855 Franchot France Le moteur sériaire à air chaud de Franchot
1867 Lehmann Germany Lehmann'sche Luftexpansionmaschine
1875 Rider America Rider's hot air engine
1881 Robinson England Robinson's hot air engine