// PROPULSION SYSTEMS AND ENGINE TECHNOLOGY TERM
Gas Generator Cycle
A type of liquid-propellant rocket engine where a small amount of propellant is burned in a separate chamber, called a gas generator, to create hot gas. This gas powers the turbines that pump fuel and oxidizer into the main combustion chamber, and is then exhausted overboard without creating thrust.
TECHNICAL DEFINITION
The Gas Generator Cycle is an open-cycle rocket engine architecture where a portion of the propellant is combusted in a separate gas generator to produce hot gas, which drives the turbopumps feeding the main combustion chamber. The turbine exhaust is then vented overboard, resulting in lower specific impulse (Isp) compared to closed-cycle designs but offering simpler, more reliable operation.
BACKGROUND
A gas generator is a device for generating gas. A gas generator may create gas by a chemical reaction or from a solid or liquid source, when storing a pressurized gas is undesirable or impractical.
READ MORE ON WIKIPEDIASYNONYMS & ALIASES
- Open Cycle
- GG Cycle
- Gas Generator Engine
- Turbopump-fed open cycle
USAGE NOTE
This cycle is favored for its proven reliability and lower development cost, as seen in engines like the Merlin, F-1, and Vulcain.
DEVELOPERS
Organizations developing technology related to Gas Generator Cycle.
Develops the Merlin engine family, a prominent example of a gas-generator cycle engine, which powers the Falcon 9 and Falcon Heavy launch vehicles. The Merlin is known for its high reliability and role in reusable rocket technology.
A major American aerospace manufacturer with a long history of developing rocket engines. They produced the RS-68, a powerful hydrogen-fueled gas-generator cycle engine that served as the main engine for the Delta IV rocket.
The prime contractor for Europe's Ariane launchers. They manufacture the Vulcain engine, the cryogenic gas-generator cycle core stage engine for the Ariane 5 and Ariane 6 rockets.
A leading Russian rocket engine company. It is the developer of the RD-107/RD-108 family of engines, which use a gas-generator cycle and have reliably powered the Soyuz launch vehicles for over 60 years.
An aerospace manufacturing company that utilizes 3D printing to build rockets. Their Aeon 1 and larger Aeon R engines are both gas-generator cycle engines powered by liquid oxygen and liquid natural gas.
Develops a portfolio of launch and in-space vehicles. The company's Reaver engine, which powers the first stage of their Alpha rocket, uses a tap-off cycle, a variation of the gas-generator engine cycle.
India's national space agency, which develops its own launch vehicles. ISRO manufactures and operates the Vikas engine, a storable liquid-propellant gas-generator engine used on its PSLV and GSLV rockets.