This presentation is about Ion Propulsion System use in rocket engines. This ppt is made by students of BS physics 7 semester of Khwaja Fareed University Of Engineering and Information Technology Rahim Yar Khan, Punjab, Pakistan.

3. CONTENTS
1. Definition
2. PARTS OF IPS(Ion Propulsion system)
3. Ion propulsion process
4. Electrostatic ion thruster
5. Amount of thrust
6. APPLICATIONS
7. Propellant
8. ADVANTAGES
9. Disadvantages
10.conclusion

4. DEFINITION
• Ion propulsion is a technology that involves ionizing a gas to propel a
craft. Instead of a spacecraft being propelled with standard chemicals,
the gas xenon is given an electrical charge, or ionized.
• It is then electrically accelerated to a speed of about 30 km/second.
• When xenon ions are emitted with the help of ion thrusters at high
speed as exhaust from a spacecraft, they push the spacecraft in the
opposite direction.

5. Ion:
• An ion is simply an atom or molecule that is electrically charged.
Ionization:
• It is a process of converting an atom or molecule into ions.
• It can done by either adding or removing electrons then they
become cation (+ve) or anion (-ve) respectively
Ion Thruster:
• An ion thruster is form of electric propulsion used for
spacecraft propulsion that creates trust by accelerating ions

6. • Ion propulsion system consists of the following five parts:
1. Power Source
2. Power Processing Unit
3. Propellant Management system
4. The Control Computer
5. Ion Thruster
PARTS OF IPS(Ion Propulsion system):

7. • A solar electric propulsion system (SEP) uses sunlight and solar cells
for power generation.
• power source can be any source of electrical power, but solar and
nuclear are the primary options.
• A nuclear electric propulsion system (NEP) uses a nuclear heat
source coupled to an electric generator.
2. Power processing unit (PPU):
• The PPU converts the electrical power generated by the power
source into the power required for each component of the ion
thruster.
• It generates the voltages required by the ion optics and discharge
chamber and the high currents required for the hollow cathodes.
1. Power Source:

8. • The PMS controls the propellant flow from the propellant tank to the thruster
and hollow cathodes.
• Modern PMS units have evolved to a level of sophisticated design that no
longer requires moving parts.
3. Propellant Management System:
5. Ion Thrusters :
• They are of two types:
1)Electrostatic
2)Electromagnetic
• The computer controls and monitors system performance then
processes the propellant and power to perform work.
4. The Computer Control :

9. • The fuel used my modern ion engines is xenon gas which is four times
heavier than air.
• When the ion engine is running, electrons are emitted from a hollow
cathode tube called as discharge cathode.
• These electrons enter a magnet-ringed chamber, where they strike the
xenon atoms.
• These electrons hits the electrons of xenon atom as it consists of 54
electrons .
• This results in the formation of ions in discharge chamber
Ion Propulsion Process:

10. • High-strength magnets are placed along the discharge chamber walls so that as
electrons approach the walls, they are redirected into the discharge chamber by
the magnetic field
• At the rear of the chamber, a pair of metal grids is charged positively and
negatively, respectively, with up to 1,280 volts of electricity.
• The force of this electric charge exerts a strong electrostatic pull on the xenon
ions.
• The xenon ions shoot out the back of the engine at high speeds which propels
the spacecraft in opposite direction and produces thrust force.
• The force of this electric charge exerts a strong electrostatic pull on the
xenon ions.

11. • The xenon ions shoot out the back of the engine at high speeds which
propels the spacecraft in opposite direction and produces thrust force.

12. • This type of thruster commonly use xenon gas which has no charge and it is
ionized by bombarding with energetic electrons.
• These electrons are provided from hot cathode filament and accelerated
into electric field of cathode fall to anode.
• The electrons can be accelerated by the oscillating electric field induced by
an alternating magnetic field of a coil which results in a self-sustaining
discharge and omits any cathode.
• The positive ions are extracted after bombarding of electrons with xenon
atoms, and these ions are accelerated by electrostatic forces.
• The electric fields used for acceleration is generated by electrodes
positioned at the end of the thruster ,such set of electrodes are called as
ion optics or grids.
Electrostatic Ion Thruster:

13. • Some ion thrusters use a two-electrode system, where the upstream
electrode(screen grid) is charged highly positive, and the downstream
electrode(accelerator grid) is charged highly negative.
• Since the ions are generated in a region of high positive and the
accelerator grid's potential is negative, the ions are attracted toward
the accelerator grid and are focused out of the discharge chamber
through the apertures, creating thousands of ion jets.
• Because the ion thruster expels a large amount of positive ions, an
equal amount of negative charge must be expelled to keep the total
charge of the exhaust beam neutral.

14. • Many current designs use xenon gas due to its low ionization energy,
reasonably high atomic number, inert nature, and low erosion.
• Ion thrusters use inert gas for propellant, eliminating the risk of explosions.
• The usual propellant is xenon, but other gases such as krypton and argon may
be used.
Propellant:
• A second hollow cathode called the neutralizer is located on
the downstream of the thruster and expels the needed
electrons that’s how an electrostatic thruster produces thrust
with the help of ions and propels the spacecraft

15. • At full throttle, the ion engine will consume 2,500 watts of
electrical power, and put out 1/50th of a pound of thrust.
• Ion thrusters are capable of propelling a spacecraft up to 90,000
meters per second (over 200,000mph).
• Thrusters can deliver up to 0.5 Newtons (0.1 pounds) of thrust.
Amount of Thrust:

17. • Ion thrusters have many applications for in-space propulsion.
• The best applications of the ion thrusters make use of the long
lifetime when significant thrust is not needed.
• This type of propulsive device can also be used for interplanetary
and deep space missions where time is not crucial.
• Used to spiral at lower altitudes on vestal.
• Helps Spacecraft Cruise Solar System on the Cheap.
Applications:

18. • Ion propulsion makes efficient use of the onboard fuel by accelerating it to a
velocity ten times that of chemical rockets.
• The ion propulsion system is although highly efficient and very gentle in its
thrust.
• With xenon, it is possible to reduce propellant mass onboard of a spacecraft
by up to 90 percent.
• The advantages of having less onboard propellant include a lighter spacecraft
and reduces launch cost.
• Additional velocity can be obtained.
• Would have greater life time when compared to other propulsive devices.
• Continuous thrust over a very long time can build up a larger velocity than
traditional chemical rockets.
Advantages:

19. • Unlike a chemical propulsion system ion propulsion produces gentle
amount of thrust but for a long duration.
• Ion propulsion system is mostly applicable only for deep space missions.
• Cost of propellant used is very expensive.
• Complex power conditioning ,high voltages
• Single propellant
• Low thrust per unit area
Disadvantages:

20. CONCLUSION
• The propellant chose should not cause erosion of the thruster to any
great degree to permit long life; and should not contaminate the
vehicle.
• More efficient than the chemical propulsion.
• In 1998, Deep Space 1 became the first spacecraft to use ion propulsion
to reach destinations in the solar system

21. IF ANY QUERIES PLEASE ASK?