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Nova engine powerpoint

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Nova engine powerpoint

  1. 1. The future of manned space exploration and development of space depends critically on the creation of a vastly more efficient propulsion architecture for in-space transportation. Nuclear-powered rockets can provide the large energy density gain required. A small scale, low cost path to fusion-based propulsion is to be investigated. It is accomplished by employing the propellant to compress and heat a magnetized plasma to fusion conditions, and thereby channel the fusion energy released into heating only the propellant. Passage of the hot propellant through a magnetic nozzle rapidly converts this thermal energy into both directed (propulsive) energy and electrical energy. Fusion-powered rockets could provide longer thrust than chemical rockets, which burn their fuel quickly. It's believed that fusion propulsion will allow rapid travel to anywhere in our solar system, and could allow round trips from Earth to Jupiter in just two years.
  2. 2. My idea of the nuclear propulsion is a fusion reaction between deuterium plasma and tritium plasma (D-T Fusion, below). In this reaction the hydrogen isotope, deuterium plasma (with one “extra” neutron) collides with the hydrogen isotope, tritium plasma (with two “extra” neutrons), to form an alpha particle (a helium nuclei ) and a neutron. This is a nuclear reaction: between them, the new alpha and the neutron possess 17.6 MeV (million electron volts) of energy. The helium nuclei will be accelerated out of a magnetic nozzle in a very high speed with the energy made by the nuclear reaction and that produces high thrust of plasma propulsion with a long duration of gas injection.
  3. 3. Producing plasma. the first RF coupler is to convert gas into plasma by ionizing it, or knocking an electron loose from each gas atom. It is known as the helicon section, because its coupler is shaped such that it can ionize gas by launching helical waves. Helicon couplers are a common method of generating plasma. After the helicon section, the gas is now "cold plasma", even though its temperature is greater than the surface of the Sun (5800 K). The plasma is a mixture of electrons and ions (the atoms they were stripped from).
  4. 4. Heating the plasma. the Ion Cyclotron Heating (ICH) section. ICH is a technique used in fusion experiments to heat plasma to temperatures on the order of those in the Sun's core (10 million K). The ICH waves push only on the ions as they orbit around the magnetic field lines resulting in accelerated motion and higher temperature.
  5. 5. Confining the plasma. Since fusion needs a hot plasma held tightly together for long enough for the fusion reaction to occur, and since the plasma is so hot it would melt any container you could put it in (like trying to boil water in a pot made from ice!!) we need to use magnetic confinement. We can see this principle is used in the tokamak. The Tokamak employs many magnetic fields to ensure the plasma stays tightly confined and away from its walls. The plasma must be dense for fusion to occur, but the temperature of the plasma gets so high that anything it touches would melt instantly. This is why extremely strong magnets are needed to keep it away from the tokamak walls.
  6. 6. Heating the combustion chamber. Fusion can only occur in super-heated environments measuring in the millions of degrees. Stars, which are made of plasma, are the only natural objects that are hot enough to create fusion reactions. In this case, the combustion chamber will be heated using radio-frequency radiation to create extreme heat and fuse the plasma. The high level of heat required to create this type of plasma makes it impossible to contain the components in any known material. However, plasma is a good conductor of electricity, which makes it possible to be held, guided and accelerated using magnetic fields. This is the basis for creating a fusion- powered spacecraft, which NASA believes is achievable within 25 years.
  7. 7. The tube. The plasma will be inside a quartz tube with spiral shape so that we get a long way to put the plasma in, because the longer the tube is, the faster the plasma will be in the outlet. Plasmaina tube
  8. 8. Accelerating the plasma. To accelerate the plasma, we use a solenoid which will be wrapped around the tube to push the ions into the combustion chamber in a very high speed.
  9. 9. Injecting the electrons. Once the gas is converted into plasma, an anode will absorb the electrons and inject them using a neutralizing electron gun. You can understand the process of the gas injection, producing the plasma, confining it, heating it up and accelerate it from these two pictures.
  10. 10. Power source. One of the key challenges in developing the NOVA engine is supplying power to it. A high-power electric thruster requires a lot of electricity, and generating that in space may require some engineering innovations. Solar power can be efficiently used for going to Mars. Spacecraft operating in the inner solar system usually rely on the use of photovoltaic solar panels to derive electricity from sunlight. In the outer solar system. Recent advances in solar array technology show a significant increase in solar power utilization (up to an order of magnitude).
  11. 11. The same principle of the producing and accelerating plasma is used in the VASIMR engine. The Variable Specific Impulse Magnetoplasma Rocket (VASIMR) engine is a new type of electric thruster with many unique advantages. In a VASIMR engine, gas such as argon, xenon, or hydrogen is injected into a tube surrounded by a magnet and a series of two radio wave (RF) couplers The couplers turn cold gas into superheated plasma and the rocket’s magnetic nozzle converts the plasma thermal motion into a directed jet.
  12. 12. Many types of nuclear propulsion have been proposed, and some of them (e.g. NERVA) tested for spacecraft applications. •Project Orion. Project Orion has to be the most audacious, dangerous and downright absurd space program ever funded by the US taxpayer. This 1950s design involved exploding nuclear bombs behind a spacecraft the size of the Empire State Building to propel it through space. The Orion’s engine would generate enormous amounts of energy – and with it lethal doses of radiation. Plans suggested the spacecraft could take off from Earth and travel to Mars and back in just three months. The quickest flight using conventional rockets and the right planetary alignment is 18 months. Project Orion was a study of a spacecraft intended to be directly propelled by a series of explosions of atomic bombs behind the craft (nuclear pulse propulsion). Early versions of this vehicle were proposed to take off from the ground with significant associated nuclear fallout; later versions were presented for use only
  13. 13. •Project Daedalus. There were three stated goals for Project Daedalus: •The spacecraft must use current or near-future technology. •The spacecraft must reach its destination within a working human lifetime. •The spacecraft must be designed to allow for a variety of target stars. The final design solution was published in a special supplement of the Journal of the British Interplanetary Society in 1978.