Context
ISRO successfully hot-tested its CE-20 cryogenic engine for sea-level ignition at ISRO Propulsion Complex
About Cryogenic Technology
- Cryogenics: The study and application of materials at ultra-low temperatures (below -160°C).
- Primary Application: Space technology, especially for rocket engines to carry heavier payloads.
- ISRO’s Achievement: India became a part of the elite group of countries with indigenous cryogenic technology in 2014 when GSLV-DF rocket was launched.
Gases Used in Cryogenics
- Cryogenic Liquids: Liquids with boiling points below -130°F.
- Common Gases: Nitrogen, Hydrogen, Oxygen, Helium, Argon
- Cryogenic Dewar: A vessel used to store cryogenic liquids; creates a vacuum space for insulation.
Applications of Cryogenic Technology
- Medical & Pharmaceutical Industry:
- Freezing substances like blood cells, stem cells, drugs, eggs.
- Used in cryosurgery to remove abnormal tissues (e.g., tumors).
- MRI systems use helium for cooling.
- Food Industry:
- Cryogenic refrigeration systems for cooling food at its best quality.
- Liquid nitrogen used for super-fast cooling of food.
- Space:
- Cryogenic fuels (liquid oxygen & liquid hydrogen) for rockets.
- Liquid helium used to cool space detectors.
- Cryogenic test chambers prepare satellites/rockets for space.
- Automotive Industry:
- Cryogenic cooling boxes used for engine block components by shrinking them using nitrogen.
- Superconductors:
- Cooling magnets to near absolute zero to create superconductors for various applications.
- Scientific Research:
- Used in Nuclear Magnetic Resonance (NMR) to determine chemical structures.
- Cryopreservation of organs, tissues, and embryos for research.
- Superconducting magnets used in particle accelerators (e.g., Large Hadron Collider).
- Transportation of Inflammable Gases:
- Cryogenics used in transporting gases like LNG and LPG.
Cryogenic Engine
- Cryogenic Engine: The final stage of a space launch vehicle using cryogenic propellants.
- Key Propellants:
- Liquid Oxygen (LOX) at -183°C
- Liquid Hydrogen (LH2) at -253°C
- Components: Combustion chamber, igniter, fuel injector, cryo pumps, gas turbines, cryo valves, regulators, fuel tanks, rocket engine nozzle.
Advantages of Cryogenic Engine
- High Energy per Unit Mass:
- Liquid propellants provide high energy, reducing the amount of fuel needed for rockets.
- Higher Payload:
- Higher specific impulse increases payload capacity.
- Fuel Density:
- Higher density of liquid fuels allows more fuel storage.
- Cooling:
- The engine is self-cooled using the propellant, eliminating the need for extra cooling systems.
- Clean Fuels:
- Hydrogen and oxygen are clean fuels; they release only water when burned.
- Non-toxic and non-corrosive properties.
- Economical:
- More thrust per kilogram of cryogenic propellant used, making it cost-effective.
Challenges in Cryogenic Technology
- Engineering Challenges:
- High-speed pumps required for liquid hydrogen delivery.
- Complex design and fabrication due to the high-speed requirements.
- Complex Storage:
- Long-term storage of cryogens for planetary exploration requires effective heat insulation and technology.
- Hazards:
- Risks of fire, explosion, pressure, frostbite, chemical toxicity, and asphyxiation.
Source: Business today
Previous Year Question
With reference to India’s satellite launch vehicles, consider the following statements:
1. PSLVs launch the satellites useful for Earth resources monitoring whereas GSLVs are designed mainly to launch communication satellites.
2. Satellites launched by PSLV appear to remain permanently fixed in the same position in the sky, as viewed from a particular location on Earth.
3. GSLV Mk III is a four-staged launch vehicle with the first and third stages using solid rocket motors; and the second and fourth stages using liquid rocket engines.
Which of the statements given above is/are correct?
[UPSC Civil Services Exam – 2018 Prelims]
(a) 1 only
(b) 2 and 3 only
(c) 1 and 3 only
(d) 3 only
Answer: (a)
Explanation:
Statement 2 is not correct: Satellites launched by GSLV appear to remain permanently fixed in the same position in the sky, as viewed from a particular location on Earth.
Statement 3 is not correct: GSLV Mk III is a three-stage heavy lift launch vehicle with two solid strap-one, a core liquid booster and a cryogenic upper stage.