Cryogenic Rocket
Engine
Meaning of Cryogenics
 In physics, cryogenics is the study of the production of very low
temperature(below −150 °C, −238 °F or 123 K) and the behavior of
materials at those temperatures .
Cryogenic technology
o Cryogenic technology involves the use of rocket propellants at
extremely low temperatures.
o The combination of liquid oxygen and liquid hydrogen offers the
highest energy efficiency for rocket engines that need to produce large
amounts of thrust.
o Oxygen remains a liquid only at temperatures below minus 183 °
Celsius and hydrogen at below minus 253 ° Celsius.
History of Cryogenic Technology
 The United States was the first country to develop cryogenic rocket
engines.
with RL-10 engines, registered its first successful flight in 1963
and is still
used on the Atlas V rocket.
 Then The Japanese LE-5 engine flew in 1977 ,French HM-7 in 1979 ,
Chinese YF-73
in 1984 .
 The Soviet Union, first country to put a satellite and later a human in
space, successfully launched a rocket with a cryogenic engine only in 1987.
The first operational cryogenic engine
Cont…….
(Russian) - N 1
(AMERICAN) - ATLAS V
Cont….
 To India the U.S., Japan and France would either not provide the technology or do
so only at an exorbitant price.
 The 11D56 cryogenic engine had been developed for one of the upper stages of the
mammoth N1 rocket, the Soviet equivalent of Saturn V. But after four successive
launch failures, the N1 project was scrapped and its engines were mothballed.
 The deal violated the Missile Technology Control Regime, which was intended to
prevent the spread of missile-related technology, and fell foul of the U.S. laws
meant to enforce its provisions. Despite warnings from within the organization,
ISRO opted to go ahead with the import. In May 1992, the U.S. imposed sanctions
on ISRO and Glavkosmos. A year later, Russia, which received the contract
after the break-up of the Soviet Union, backed out of the deal.
Cont….
 ISRO then had no option but to develop the technology on its own.
 At the time, ISRO gave the impression that much of the technology
had already been acquired and further development would be quick.
 A GSLV with an indigenous cryogenic engine would be ready to fly in
about four years, Chairman U.R. Rao told in July 1993. Instead, it has
taken 16 years.
Working
 It involves a complicated ‘staged combustion cycle' to increase the
engine efficiency.
 Hydrogen is partially burnt with a little oxygen in a gas generator. The
hot gases drive a turbo-pump and are then injected at high pressure
into the thrust chamber where the rest of oxygen is introduced and full
combustion takes place.
 Before going to the gas generator, the incredibly chilly liquid hydrogen
is used to cool the thrust chamber where temperatures rise to over
3,0000 ° Celsius when the engine is fired.
Production & Manufacturing
 The Indian cryogenic engine is produced by Godrej and the
Hyderabad-based MTAR Technologies working together as a
consortium.
 Instead of ISRO first mastering the technology and transferring it to
industry, the two companies were involved from the start and even the
early prototypes were built by them.
Why didn't the cryogenic engine of India ignite?
 The GSLV D3, which lifted off well from Sriharikota on Thursday, April
15, 2010 later plunged into the sea as the indigenous cryogenic engine
failed to ignite.
 The vehicle lifted off as planned at 4.27 p.m. and its performance was
normal up to the end of its second stage till 293 seconds from the liftoff.
 An authoritative former ISRO official said: “It is very clear that the
cryogenic engine did not ignite when you look at the curve [of the
vehicle's trajectory]
 the vehicle developed problems when the cryogenic upper stage should
have ignited 304 seconds after the lift-off, and it fell into the sea
Advantages
 High Energy per unit mass:
Propellants like oxygen and hydrogen in liquid form
give very high amounts of energy per unit mass due to
which the amount of fuel to be carried aboard the rockets
decreases.
 Clean Fuels
Hydrogen and oxygen are extremely clean fuels. When they
combine, they give out only water. This water is thrown out of the
nozzle in form of very hot vapour. Thus the rocket is nothing but
a high burning steam engine
 Economical
Use of oxygen and hydrogen as fuels is very economical, as
liquid oxygen costs less than gasoline.
Drawbacks:
 Boil off Rate
 Highly reactive gases
 Leakage
 Hydrogen Embrittlement
 Zero Gravity conditions
The next generation of the
Rocket Engines
 All rocket engines burn their fuel to generate thrust . If any other
engine can generate enough thrust, that can also be used as a
rocket engine
 There are a lot of plans for new engines that the NASA scientists
are still working with. One of them is the “ Xenon ion Engine”.
This engine accelerate ions or atomic particles to extremely high
speeds to create thrust more efficiently. NASA's Deep Space-1
spacecraft will be the first to use ion engines for propulsion.
 There are some alternative solutions like Nuclear thermal rocket
engines, Solar thermal rockets, the electric rocket etc.
 We are looking forward that in the near future there will be some
good technology to take us into space
Any Queries