3. CRYOGENIC
Cryogenic is derived from greek , Kryos means cold , genes means
production.
Cryogenic is the study of production and behavior of materials at very
low temperature (Below 150*C ,123*K,-238*F)
Oxygen liquefies at -183*C
Hydrogen liquefies at -253*C
4. INTRODUCTION
1. A cryogenic rocket engine is a engine which use cryogenic fuel.
2. Cryogenic fuel are fuel that requires storage at extremely low
temperature in order to maintain the in a liquid state.
3. Various cryogenic fuel-oxidizer combination have been fired but
the combination of liquid hydrogen (LH2), and the liquid oxygen
(LOX) oxidizer is most used.
5. RL-10
The RL-10 was the first liquid Hydrogen
Cryogenic engine to nr built in the
United States, and development of the
engine by Marshall Space Flight Center
and Pratt & Whitney began in the 1950s,
with the first flight occurring in 1961
These engines were one of the main
factors of NASA's success in reaching
the Moon by the Saturn V rocket
6. CE 7.5
The specifications and key characteristics of
the engine are:
Operating Cycle - Staged combustion
Propellant Combination - LOX / LH2
Maximum thrust (Vacuum) - 75 KN
Operating Thrust Range -73.55 kN to 82 kN
Chamber Pressure (Nom) - 58 bar
Engine Mixture ratio (Oxidizer/Fuel by mass) -
5.05
Engine Specific Impulse - 454 ± 3 seconds
(4.452 ± 0.029 km/s)
Engine Burn Duration (Nom) - 720 seconds
Propellant Mass - 12800 kg
7. CE-20
The specifications of the engine as listed on the
Operating Cycle-Gas Generator
Propellant Combination - LCX/LHE
Thrust Nominal (Vacuum) - 200 KN
Operating Thrust Range - 180 KN to 220 KN
(To be set at any fix values)>
Chamber Pressure (Nom) - 6 Mpa
Engine Mixture ratio (Oxidizer/Fuel by
weight) -5.05
Engine Specific Impulse = 443 + 3 seconds
(4.344 ± 0.029 km/s)
Engine Burn Duration (Nom)-595 seconds
Total Flow rate-462 kg/s
Nozzle Area ratio-100
Mass-588 kg
8. CONSTRUCTION
pyrotechnic igniter
fuel injector
fuel turbo-pumps
gas turbine-
cryo valves
Regulators
The fuel tanks
rocket engine- nozzle
9. PRINCIPLE
The basic principle driving a rocket engine are:
Newton third law of motion
Law of conservation of momentum
In principle, cryogenic rocket engine derives thrust like all other rocket engines by
accelerating an impulse carrier to high speeds.
The chemical energy stored in the fuel is converted into kinetic energy by burning the fuel
in the thrust chamber and subsequent expansion in the nozzle to produce thrust
10.
11. APPLICATIONS OF CRYOGENICS
Cryogenic fuels
Liquid nitrogen: used in cryo-therapy, as a coolant, cryonic preservation
Nuclear magnetic resonance spectroscopy: NMR is one of the most common methods to
determine the physical and chemical properties of atoms by detecting the radio frequency
absorbed and subsequent relaxation of nuclei in a magnetic field.
Frozen food: Cryogenic gases are used in transportation of large masses of frozen food.
Blood banking: Certain rare blood groups are stored at low temperatures, such as −165 °C.
12. ADVANTAGE AND DISADVANTAGE
ADVANTAGE
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.
DISADVANTAGE
Boil off Rate
Cryogenic fluid are difficult to store for longer
period
Highly reactive gases
Zero gravity condition
Leakage
High density requires larger tank
Hydrogen Embrittlement
