Difference between revisions of "Nuclear thermal propulsion"

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Nuclear thermal propulsion uses a nuclear core to heat a propellant and provide propulsion to a space vehicle.
 
Nuclear thermal propulsion uses a nuclear core to heat a propellant and provide propulsion to a space vehicle.
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Liquid hydrogen is usually used as the propellant as it has a higher velocity for the same input power, and therefore produces a faster final velocity according to the [[Propulsion|rocket equation]].
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__NOTOC__
 
__NOTOC__
 
==History of nuclear thermal propulsion==
 
==History of nuclear thermal propulsion==
  
 
===American===
 
===American===
Nerva<ref>Nerva on Wikipedia: https://en.wikipedia.org/wiki/NERVA</ref>
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Nerva<ref>Nerva on Wikipedia: https://en.wikipedia.org/wiki/NERVA</ref>
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{| class="wikitable"
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!Propellant
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|Liquid hydrogen
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|-
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! colspan="2" |Performance
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|-
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!Thrust (vac.)
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|246,663 N (55,452 lb<sub>f</sub>)
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|-
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!Chamber pressure
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|3,861 kPa (560.0 psi)
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|-
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!''I''<sub>sp</sub> (vac.)
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|841 seconds (8.25 km/s)
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|-
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!''I''<sub>sp</sub> (SL)
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|710 seconds (7.0 km/s)
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|-
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!Burn time
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|1,680 seconds
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|-
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!Thrust to weigh ratio
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!1.36
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|-
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!Restarts
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|24
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|-
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! colspan="2" |Dimensions
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|-
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!Length
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|6.9 meters (23 ft)
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|-
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!Diameter
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|2.59 meters (8 ft 6 in)
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|-
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!Dry weight
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|18,144 kilograms (40,001 lb)
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|}
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*
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*
  
 
===Russian===
 
===Russian===
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*Lower ISP than electric
 
*Lower ISP than electric
 
*Low public trust
 
*Low public trust
*Thrust to weight ratio usually lower than 1 (cannot take off from a planet)
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*Thrust to weight ratio close to 1 (cannot take off from Earth with a significant payload)
  
 
===Types===
 
===Types===
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*Nuclear light bulb, open and closed
 
*Nuclear light bulb, open and closed
  
== References ==
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==References==
 
<references />
 
<references />

Latest revision as of 10:38, 9 August 2019

Nuclear thermal propulsion uses a nuclear core to heat a propellant and provide propulsion to a space vehicle.

Liquid hydrogen is usually used as the propellant as it has a higher velocity for the same input power, and therefore produces a faster final velocity according to the rocket equation.


History of nuclear thermal propulsion

American

Nerva[1]

Propellant Liquid hydrogen
Performance
Thrust (vac.) 246,663 N (55,452 lbf)
Chamber pressure 3,861 kPa (560.0 psi)
Isp (vac.) 841 seconds (8.25 km/s)
Isp (SL) 710 seconds (7.0 km/s)
Burn time 1,680 seconds
Thrust to weigh ratio 1.36
Restarts 24
Dimensions
Length 6.9 meters (23 ft)
Diameter 2.59 meters (8 ft 6 in)
Dry weight 18,144 kilograms (40,001 lb)

Russian

Analysis of use

Advantages

  • Higher ISP than chemical
  • Higher power energy source
  • Shorter travel time
  • Oberth effect
  • Self cooling

Disadvantages

  • Cost
  • Cost of development
  • Risk of accident
  • Lower ISP than electric
  • Low public trust
  • Thrust to weight ratio close to 1 (cannot take off from Earth with a significant payload)

Types

  • Solid core
  • Gas core
  • Nuclear light bulb, open and closed

References