Thermal Nuclear Propulsion - Revision history

RichardWSmith: /* Disadvantages of Thermal Nuclear Propulsion */ Explained an abbreviation.

2024-10-22T02:35:34Z

Disadvantages of Thermal Nuclear Propulsion: Explained an abbreviation.

← Older revision		Revision as of 03:35, 22 October 2024
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	*Many people fear nuclear power, sometimes beyond the bounds of reason, which may cause political complications. As the engines need to be tested on the ground, this creates risks that can be perceived as too high.		*Many people fear nuclear power, sometimes beyond the bounds of reason, which may cause political complications. As the engines need to be tested on the ground, this creates risks that can be perceived as too high.
	*Nuclear fuel, in particular enriched nuclear fuel, is hard to obtain for civilians. This makes the development of nuclear engines difficult.		*Nuclear fuel, in particular enriched nuclear fuel, is hard to obtain for civilians. This makes the development of nuclear engines difficult.
	*If high thrust is not needed, NEP offers much higher exhaust velocities for the same energy input. So the propellant efficiency is higher.		*If high thrust is not needed, Nuclear Electric Propulsion (NEP) offers much higher exhaust velocities for the same energy input. So the propellant efficiency is higher.
	*If propellant is cheap, then there is no economical advantage in 'saving' propellant. Therefore, the cost of developing a full TNP engine and rocket must be compared to the cost of just using more propellant for chemical rockets.		*If propellant is cheap, then there is no economical advantage in 'saving' propellant. Therefore, the cost of developing a full TNP engine and rocket must be compared to the cost of just using more propellant for chemical rockets.

RichardWSmith: /* MITEE */ Added link.

2024-10-17T21:08:49Z

MITEE: Added link.

← Older revision		Revision as of 22:08, 17 October 2024
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	===MITEE===		===MITEE===
	The MITEE (MIniature Reac Tor EnginE) was a design for a very light nuclear Thermal rocket. While the thrust to weight ratio of the NERVA engines was close to one (the Nerva engine can barely lift itself), the MITEE theoretically achieved a thrust to weigh ratio of 10, making it a candidate for missions that could lift from the surface of practically any planet, including the atmosphere of Uranus or Neptune. Or obviously, Mars. The MITEE engine heats hydrogen propellant to 3000 K, achieving a specific impulse of 1000 seconds, with a thrust of 28 000 Newtons and a total engine mass is 200 kg, including reactor, pump, auxiliaries and a 30% contingency.		The MITEE (MIniature Reac Tor EnginE) was a design for a very light nuclear Thermal rocket. While the thrust to weight ratio of the NERVA engines was close to one (the Nerva engine can barely lift itself), the MITEE theoretically achieved a thrust to weigh ratio of 10, making it a candidate for missions that could lift from the surface of practically any planet, including the atmosphere of Uranus or Neptune. Or obviously, Mars. The MITEE engine heats hydrogen propellant to 3000 K, achieving a specific impulse of 1000 seconds, with a thrust of 28 000 Newtons and a total engine mass is 200 kg, including reactor, pump, auxiliaries and a 30% contingency.
	MITEE requires significant amounts of very highly enriched uranium, and therefore is difficult to test and implement, in particular for a civil space program.		MITEE requires significant amounts of very highly enriched uranium, and therefore is difficult to test and implement, in particular for a civil space program. See <ref>https://www.osti.gov/servlets/purl/432864 \| MITEE</ref> for more information.

	==Discussion==		==Discussion==

RichardWSmith: /* References */

2024-10-16T05:24:13Z

References

← Older revision		Revision as of 06:24, 16 October 2024
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	==References==		==References==
	1- https://ntrs.nasa.gov/citations/19950005290		1- https://ntrs.nasa.gov/citations/19950005290

	2- https://ui.adsabs.harvard.edu/abs/2001iaop.work...66P/abstract		2- https://ui.adsabs.harvard.edu/abs/2001iaop.work...66P/abstract

	[[Category:Propulsion]]		[[Category:Propulsion]]

RichardWSmith: /* Disadvantages of Thermal Nuclear Propulsion */ refrigerators require more mass.

2024-10-16T05:23:22Z

Disadvantages of Thermal Nuclear Propulsion: refrigerators require more mass.

← Older revision		Revision as of 06:23, 16 October 2024
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	*Nuclear reactors tend to be large, thus this is best for large ships.		*Nuclear reactors tend to be large, thus this is best for large ships.
	*Hydrogen is not very dense, so large tanks are required to hold it.		*Hydrogen is not very dense, so large tanks are required to hold it.
	*Hydrogen is not space storable, as it warms it expands and must be bled off, wasting reaction mass. This might be alleviated using refrigeration and cooling system, but this adds complexity.		*Hydrogen is not space storable, as it warms it expands and must be bled off, wasting reaction mass. This might be alleviated using refrigeration and cooling system, but this adds complexity & mass.
	*Nuclear reactors can not be instantly turned on and off. Thus the thrust will taper on and off.		*Nuclear reactors can not be instantly turned on and off. Thus the thrust will taper on and off.
	*Many people fear nuclear power, sometimes beyond the bounds of reason, which may cause political complications. As the engines need to be tested on the ground, this creates risks that can be perceived as too high.		*Many people fear nuclear power, sometimes beyond the bounds of reason, which may cause political complications. As the engines need to be tested on the ground, this creates risks that can be perceived as too high.

Michel Lamontagne: /* Summary */

2024-10-15T21:27:37Z

Summary

← Older revision		Revision as of 22:27, 15 October 2024
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	==Summary==		==Summary==
	TNP is a worthy form of rocket, which deserves further development. However, it is difficult for it to compete with chemical propulsion using cheap propellant mass, such as used by fully reusable Methane-Oxygen engines. This suggests that early ships are unlikely to use it. For short trips in the Cis-Lunar space or as a Mars shuttle it may be an excellent long term solution.		TNP is a worthy form of rocket, which deserves further development. However, it is difficult for it to compete with chemical propulsion using cheap propellant mass, such as used by fully reusable Methane-Oxygen engines. This suggests that early ships are unlikely to use it. For short trips in the Cis-Lunar space or as a Mars orbital shuttle it may be an excellent long term solution.

	==References==		==References==

Michel Lamontagne: /* Disadvantages of Thermal Nuclear Propulsion */

2024-10-15T21:26:44Z

Disadvantages of Thermal Nuclear Propulsion

← Older revision		Revision as of 22:26, 15 October 2024
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	*Nuclear fuel, in particular enriched nuclear fuel, is hard to obtain for civilians. This makes the development of nuclear engines difficult.		*Nuclear fuel, in particular enriched nuclear fuel, is hard to obtain for civilians. This makes the development of nuclear engines difficult.
	*If high thrust is not needed, NEP offers much higher exhaust velocities for the same energy input. So the propellant efficiency is higher.		*If high thrust is not needed, NEP offers much higher exhaust velocities for the same energy input. So the propellant efficiency is higher.
			*If propellant is cheap, then there is no economical advantage in 'saving' propellant. Therefore, the cost of developing a full TNP engine and rocket must be compared to the cost of just using more propellant for chemical rockets.

	==Summary==		==Summary==

Michel Lamontagne: /* Summary */

2024-10-15T21:23:23Z

Summary

← Older revision		Revision as of 22:23, 15 October 2024
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	==Summary==		==Summary==
	TNP is a worthy form of rocket, which deserves further development. However~~, as its advantages grow as the size of the ship increases~~, it is ~~less practical~~ for ~~smaller space craft~~. This suggests that early~~, small~~ ships are unlikely to use it. For short trips in the Cis-Lunar space it may be an excellent long term solution.		TNP is a worthy form of rocket, which deserves further development. However, it is difficult for it to compete with chemical propulsion using cheap propellant mass, such as used by fully reusable Methane-Oxygen engines. This suggests that early ships are unlikely to use it. For short trips in the Cis-Lunar space or as a Mars shuttle it may be an excellent long term solution.

	==References==		==References==

Michel Lamontagne: /* MITEE */

2024-10-15T21:20:05Z

MITEE

← Older revision		Revision as of 22:20, 15 October 2024
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	Hydrogen mass and volume is also reduced resulting in smaller space vehicles. As soon as any form of industrial base is established, Oxygen from the Moon, or Mars, will be much cheaper than hydrogen from Earth.		Hydrogen mass and volume is also reduced resulting in smaller space vehicles. As soon as any form of industrial base is established, Oxygen from the Moon, or Mars, will be much cheaper than hydrogen from Earth.
	===MITEE===		===MITEE===
			The MITEE (MIniature Reac Tor EnginE) was a design for a very light nuclear Thermal rocket. While the thrust to weight ratio of the NERVA engines was close to one (the Nerva engine can barely lift itself), the MITEE theoretically achieved a thrust to weigh ratio of 10, making it a candidate for missions that could lift from the surface of practically any planet, including the atmosphere of Uranus or Neptune. Or obviously, Mars. The MITEE engine heats hydrogen propellant to 3000 K, achieving a specific impulse of 1000 seconds, with a thrust of 28 000 Newtons and a total engine mass is 200 kg, including reactor, pump, auxiliaries and a 30% contingency.
			MITEE requires significant amounts of very highly enriched uranium, and therefore is difficult to test and implement, in particular for a civil space program.

	==Discussion==		==Discussion==

Michel Lamontagne: /* references */

2024-10-15T21:12:19Z

references

← Older revision		Revision as of 22:12, 15 October 2024
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	TNP is a worthy form of rocket, which deserves further development. However, as its advantages grow as the size of the ship increases, it is less practical for smaller space craft. This suggests that early, small ships are unlikely to use it. For short trips in the Cis-Lunar space it may be an excellent long term solution.		TNP is a worthy form of rocket, which deserves further development. However, as its advantages grow as the size of the ship increases, it is less practical for smaller space craft. This suggests that early, small ships are unlikely to use it. For short trips in the Cis-Lunar space it may be an excellent long term solution.

	==~~references~~==		==References==
	1- https://ntrs.nasa.gov/citations/19950005290		1- https://ntrs.nasa.gov/citations/19950005290
	2- https://ui.adsabs.harvard.edu/abs/2001iaop.work...66P/abstract		2- https://ui.adsabs.harvard.edu/abs/2001iaop.work...66P/abstract

	[[Category:Propulsion]]		[[Category:Propulsion]]

Michel Lamontagne: /* references */

2024-10-15T21:12:10Z

references

← Older revision		Revision as of 22:12, 15 October 2024
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	==references==		==references==
	1- https://ntrs.nasa.gov/citations/19950005290		1- https://ntrs.nasa.gov/citations/19950005290
			2- https://ui.adsabs.harvard.edu/abs/2001iaop.work...66P/abstract

	[[Category:Propulsion]]		[[Category:Propulsion]]