CRYOGENIC ENGINE

Cryogenic Engine

A cryogenic engine/ cryogenic stage are the last stage of space launch vehicles which makes use of Cryogenics.
Cryogenics is the study of the production and behavior of materials at extremely low temperatures (below -150 degree centigrade) to lift and place the heavier objects in space.
Cryogenic stage is technically a much more complex system with respect to solid or liquid propellant (stored on earth) stages due to the usage of propellants at extremely low temperatures.
A cryogenic engine provides more force with each kilogram of cryogenic propellant it uses compared to other propellants, such as solid and liquid propellant rocket engines and is more efficient.
Cryogenic engine makes use of Liquid Oxygen (LOX) and Liquid Hydrogen (LH2) as propellants which liquefy at -183 deg C and -253 deg C respectively. LOX and LH2 are stored in their respective tanks.
From there they are pumped in to turbo pump by individual booster pumps to ensure a high flow rate of propellants inside the combustion/thrust chamber.
The major components of a cryogenic rocket engine are combustion/thrust chamber, igniter, fuel injector, fuel cryo pumps, oxidizer cryo pumps, gas turbine, cryo valves, regulators, the fuel tanks and a rocket engine nozzle.
Cryogenic fuels are fuels that require storage at extremely low temperatures in order to maintain them in a liquid state. These fuels are used in machinery that operates in space (e.g. rocket ships and satellites) because ordinary fuel cannot be used their due to the very low temperatures often encountered in space, and due to absence of an environment that supports combustion (on Earth, oxygen is abundant in the atmosphere, whereas human-explorable space is a vacuum where oxygen is virtually non-existent). Cryogenic fuels most often constitute liquefied gases such as liquid hydrogen.
Quite often, liquid oxygen is mistakenly called cryogenic fuel, though it is actually an oxidizer and not a fuel.

Why is Cryogenic Technology important for India?

Crucial for the advancement of the Space Programme – Cryogenic Engine is used by ISRO for its GSLV Programme.
Lighter weight - High energy per unit mass is released which makes it Economical.
Missile Programme for the Defense- Cryogenic technology is useful for the development of futuristic rocket engines.
Clean technology - Cryogenic technology uses Hydrogen and oxygen as fuel and releases water as a by-product. This is one of its greatest achievements as no pollution is caused by its use.
Edge over other countries - Earlier India was refused to be helped with technology by other countries. Only the US, Japan, France, Russia & China had this technology. Now, India stands neck to neck with them.

Applications of Cryogenic Technology

In Rocket Engine
Frozen Food
Blood Banking
Infrared Sensors
Electronics
X-Rays
Preservation of Bodies
Grinding
Superconductivity

Do you know?

Until now, India was dependent on French Guiana for launching communication satellites which are heavy i.e of 5 to 6 tonnes. But last year, Hindustan Aeronautics Limited developed the biggest cryogenic propellant tank (C32 LH2) and delivered it to ISRO. The C32-LH2 tank is a developmental cryogenic propellant tank of aluminium alloy designed for improving the payload capability of GSLV MK-III launching vehicle. The four metre diametric tank is of eight-metre length to load 5,755 Kg propellant in the 89 cubic-metre volume. With C32 LH2 India’s dependency on a foreign country will come to an end. It will mark an era of self reliance.