An Introduction to Cryogenic Engine

The cryogenic engine is crucial to development of GSLV (Geo-Synchronous Satellite Launch Vehicle). Cryogenics refer to technology of sub zero temperatures and cryogenic engines use liquid oxygen as the oxidiser and liquid hydrogen as the fuel. Use of the liquefied fuel instead of solid fuels helps the engine produce greater thrust.

The engine's capability is thus of placing a far heavier payload. The technology is complicated use of special insulation and materials that can withstand temperatures of minus 200 degree or less (the boiling point of liquid hydrogen is minus 253 degree Celsius) is necessary.

On February 16, 2000 ISRO crossed an important milestone in the development of indigenous cryogenic upper stage for the GSLV when the first cryogenic engine was ignited at the LPSC (Liquid Propulsion Systems Centre), Mahendragiri.

The engine had employed liquid hydrogen and liquid oxygen. The test of the first cryogenic engine had several accomplishments such as fabrication, assembly and integration of complete cryogenic engine.

The engine made by LPSC was expected to be used as the upper stage in the third launching of the GSLV. The upper stage of earlier launches of GSLV would be powered by engines and systems imported from Russia.

The advantage of the cryogenic engine was that it would develop one-and-a-half times the thrust of conventional liquid rocket engines using fuel storable at room temperature.

The GSLV is capable of injecting 2,500 kg class communication satellites into Geo-synchronous circular orbits at an altitude of 3,600 km. It is a high risk high technology and would help bridge the gap between the number of satellites being made by India and the vehicles needed for their launch. The gap is expected to be bridged in three to four years.

India pays $70 million to Arian space for launch of INSAT satellites. By gaining the capability to place multipurpose satellite in orbit, this amount can be saved. Besides, India can enter the multi-billion dollar market for launching communications satellite.

The realisation of the cryogenic technology would also help India to become a partner in space explorations and activities of other countries. On August 13, 2001 the central government has approved the ISRO's project to send a payload to moon for which India has got capability and technology.