Cryogenic engine

Cryogenic engine

Subject: Science and Technology

Context:

The launch of Indian Space Research Organisation (ISRO)’s much-anticipated geostationary earth observation satellite, EOS-03, resulted in an unsuccessful mission after the GSLV’s cryogenic upper stage failed to ignite in space and carry the payload to its designated orbit.

What is a cryogenic engine?

• Cryogenic engines are typically very powerful and carry liquid propellant at extremely low temperatures.
• They are complex but highly efficient and provide better thrust for each kilogram of fuel burnt when compared to the traditional solid and liquid propellant rocket stages.
• Cryogenic engines were a crucial part of National Aeronautics and Space Administration (NASA)’s Apollo missions to the moon, and were also used by the GSLV for the Chandrayaan-2 mission.
• Only six countries have developed their own cryogenic engines: the US, France/European Space Agency, Russia, China, Japan, and India.
• Cryogenic engine typically makes use of liquid oxygen (LOX), which liquifies at -183 deg C, and liquid hydrogen (LH2), which liquefies at -253 deg C. LH2 acts as the fuel while LOX acts as the oxidiser that explosively reacts with the hydrogen, producing thrust. When the engine ignites, the two liquids are pushed into a combustion chamber by booster pump continuousl.
• ISRO’s cryo stage, called the C25, came after the successful flights of the earlier versions developed for previous GSLV launchers. It was designed by the Liquid Propulsion Systems Center, in collaboration with Vikram Sarabhai Space Centre, ISRO Propulsion Complex and Satish Dhawan Space Centre.
• C25’s tanks carry over 27,000 kg of fuel and fire for approximately 720 seconds. During this time, the engine develops a thrust of 73.55kN in vacuum.

Impact of failure of cryogenic engine

Missions like Gaganyaan and Chandrayaan-3 will be launched on GSLV Mk-III, a more advanced version of the GSLV rocket that is designed to carry much heavier payloads into space. GSLV Mk-III too uses an indigenously-developed cryogenic engine in the upper stage, but, unlike the one in Mk-II, this is not a reverse-engineered Russian engine.

Instead, the cryogenic engine used in GSLV Mk-III, called CE20, has been the result of over three decades of research and development, starting from scratch, and uses a different process to burn fuel. It is closer to the designs used in the Arianne rockets that were used by ISRO earlier to send its heavier satellites into space.