nuclear space engine - would it work ??

Jochem Huhmann wrote:
Pat Flannery writes:

Matt Giwer wrote:

But the first practical test of an ion engine was only a two years ago
after decades of easy, safe ground based lab research.

No, there was Deep Space 1, and decades before that SERT II (although
the NASA PAO seems to have oddly forgotten that mission when it was
talking about Deep Space 1):
http://www.grc.nasa.gov/WWW/ion/past/70s/sert2.htm

And I even dimly remember some russian, err, soviet mission with an
(experimental?) ion engine much earlier... can't find it right now. It
was some interplanetary probe, I think.


Jochem



Soviet Mars Propulsion - Nuclear Electric

Nucear electric ship
Credit - © Mark Wade
The serious development of nuclear electric propulsion began after
issuance of the decree of 23 June 1960, as a result of which ten design
bureaux and other organisations tackled technical questions related to
its development. OKB-1 specialised in theoretical studies, experimental
tests, materials technology, and equipment trials (including reactors).
Korolev decided to collaborate with TsNII-58 (Chief Designer V G
Grabin) for the reactor. This design bureau had designed the water
moderated reactors which were already providing power in Tashkent,
Riga, Kiev, Alma-Ata, Hungary, Rumania, DDR, Czechoslovakia, and Egypt.
Grabin was at that time developing the first experimental fast neutron
reactors using liquid metal cooling (SR-1 and SR-3) which were in
operation in Obninsk at the Physics-Energy Institute (FEI).

In the beginning, development and test work was oriented towards
providing power for an electric engine for manned interplanetary
flight. The nuclear electric engines for the initial TMK-E Mars
spacecraft design of 1960 used 7 MW of nuclear power. Later reactor
research was expanded to cover application of nuclear power for
scientific, economic, and military objectives in space.

OKB-1 and FEI studied various methods for transforming the reactor's
thermal energy to electrical energy to power the engine (steam
turbines, gas turbines, MHD, and direct thermo-electric conversion).
This analysis indicated that direct thermo-electric conversion was
clearly the best approach.

First stage testing of nuclear electric propulsion began in 1962 and
the original draft project N1 of that year foresaw the use of this form
of propulsion in multi-module orbital base stations and interplanetary
spacecraft. In 1965 Section 12 (Manager I I Raikov) of OKB-1 completed
work with FEI on a draft project for a nuclear electric propulsion
engine YaERD-2200 for interplanetary crewed spacecraft. The YaERD-2200
consisted of two independent stages. Each had a nuclear reactor and an
electric engine, with electrical output of each being 2,200 kW and
total thrust 8.3 kgf.

The engine featured direct thermo-electric conversion using a fast
neutron reactor; a coolant system using low activity isotope Lithium-7
in a single loop shared by both the reactor and engine; and an electro
plasma engine with an efficiency of 55% and a specific impulse of 5500
sec

The reactor / engine design was upgraded to 5,000 kW total power in
1966-1970. The revised design could be used in single block (YaE-1 and
YaE-1M) and multiple block (YaE-2 and YaE-3) applications. A single
Block YaE-1 would have an electrical output of 2,500-3,200 kW with fuel
for 4,000 to 8,000 hours of operation. Block YaE-1M would have an
output of 5000 kW. Total thrust of the engine would be from 6.2 to 9.5
kgf with a specific impulse of from 5,000 to 8,000 sec. In three block
applications, electric capacity would be 3 x 3,200 kW and 3 x 5,000 kW.
The Aelita MEK design of 1969 used a total of 15,000 kW.

Development of nuclear electric propulsion continued throughout the
1970's. In accordance with the decrees of 8 June 1971 and 15 June
1976 this was now concentrated on development of the more modest
nuclear electric rocket stage 11B97. This stage would have an electric
capacity of 500-600 kW and would use specialised plasma-ion electric
engines using standing plasma waves and anodes. In 1975 nuclear
electric propulsion work was reorganised within NPO Energia into a
special complex 7 (Manager M V Melnikov). In 1984 it was renamed
section 7 (Manager P I Bistrov, and from 1993 Y A Bakanov). Through all
these reorganisations functional test of the reactor and engine
components continued. Concepts for the direct thermoelectric
transformation of energy could not be realised without a new class of
refractory and high temperature materials, new heat pipe concepts, and
other new technology. To develop these technologies it was necessary to
build new materials test facilities, high temperature tests stands, new
experimental shops to develop methods to handle and work new refractory
alloys (niobium, molybdenum, wolfram, vanadium) and insulative and
magnetic materials.

From 1966 to 1982 many test stands were built to develop these
materials and test components of the systems. The final result was the
11B97 engine, powered from a reactor with a 200 litre core containing
30 kg of uranium fuel. In 1978 this engine was studied for use as a
reusable interorbital space tug for launch by Energia-Buran. In 1982,
according to the decree of 5 February 1981, NPO Energia developed for
the Ministry of Defence the interorbital tug Gerkules with 550 kW
maximum output and continuous operation in the 50-150 kW range for 3 to
5 years. In 1986 an interorbital tug was studied to solve the specific
application of transporting heavy satellites of 100 tonnes to
geostationary orbit, launched by Energia.

In 1986 RKK Energia updated the 1969 MEK design for launch by the new
Energia launch vehicle. The propulsion section was essentially the same
except that for safety reasons two completely independent redundant
reactor / engine assemblies were used in the place of the single unit
of the MEK design.

Energia retained the electric engines of the 1969 MEK design but
dropped the nuclear reactor for its 1989 Mars expedition design. This
spacecraft used the same thruster arrays requiring the same power
output (15 MW) as the 1986 nuclear design. But in this case two
enormous panels, each 200 m x 200 m would generate a total of 15 MW of
power at earth. The use of ultra-thin (less than 50 micrometer) / low
mass (0.2 kg per square meter) photovoltaic cells with a high specific
power value (up to 200 W per square meter) minimised the weight of
these vast arrays. The total mass of the electric engines, structure,
and solar panels was 40 tonnes. The power generated would be used
primarily by two ion engine clusters mounted perpendicular to the
living block. In high-power mode these would have a specific impulse of
3500 seconds. They would consume 165 tonnes of xenon propellant during
the voyage (of 355 tonnes total spacecraft mass).

In the 1990's Energia studied use of nuclear electric propulsion for
the scientific development project 'Mars - Nuclear electric propulsion
Stage' under contract to the Russian Space Agency and the project 'Star
- Soarer' under contract to the Ministry of Atomic Industry. These
studies looked at designs for the 2005 period. At the beginning of the
1990's a new type of nuclear generator was studied, that would have a
capacity of 150 kW in the transport role and provide 10-40 kW to power
spacecraft systems while coasting. This was designated ERTA
(Elecktro-Raketniy Transportniy Apparat). Technologies and concepts for
this engine were studied by FEI and other organisations. A modular
concept was adopted. In 1994 ERTA was studied for launch by Titan,
Ariane 5, or Energia-M launch vehicles. The reactor weight was 7,500 kg
and it could provide up to 10 years of electrical power traded off
against 1.5 years of powered flight.

Aside from this work on the 150 kW design, there was also an
examination at the same time of the use of nuclear electric propulsion
for Mars expeditions. Single and multiple launch approaches were
considered. For a single-launch complex of 150 tonnes a nuclear
electric propulsion unit of 5 to 10 MW with enough fuel for 1.5 years
would be required. For the multiple launch design, a power of 1 to 1.5
MW and fuel for three years would be required.

In 1994-95, RKK Energia, and NASA's Jet Propulsion Laboratory analysed
the project 'Mars Together'. This studied the use of spacecraft using
solar arrays or nuclear reactors of up to 30 to 40 kW for insertion
into Martian orbit and operation of a side-looking radar to digitally
map the surface. As a preliminary step a demonstration launch was
proposed of a spacecraft with a mass of 120 to 150 kg, a solar panel
area of 30 square meters and engines with a thrust of 3 kW. Objectives
of the experiment would be understanding of the changing of the orbital
altitude with continuous work of the ion engine for several hundred
hours.
http://www.astronautix.com/articles/sovctric.htm

Jochem Huhmann wrote:
Pat Flannery writes:

Matt Giwer wrote:

But the first practical test of an ion engine was only a two years ago
after decades of easy, safe ground based lab research.

No, there was Deep Space 1, and decades before that SERT II (although
the NASA PAO seems to have oddly forgotten that mission when it was
talking about Deep Space 1):
http://www.grc.nasa.gov/WWW/ion/past/70s/sert2.htm

And I even dimly remember some russian, err, soviet mission with an
(experimental?) ion engine much earlier... can't find it right now. It
was some interplanetary probe, I think.


Jochem

--
"A designer knows he has arrived at perfection not when there is no
longer anything to add, but when there is no longer anything to take away."
- Antoine de Saint-Exupery

Soviet Mars Propulsion - Nuclear Electric topic index
site index
surprise me!

Nucear electric ship
Credit - © Mark Wade
The serious development of nuclear electric propulsion began after
issuance of the decree of 23 June 1960, as a result of which ten design
bureaux and other organisations tackled technical questions related to
its development. OKB-1 specialised in theoretical studies, experimental
tests, materials technology, and equipment trials (including reactors).
Korolev decided to collaborate with TsNII-58 (Chief Designer V G
Grabin) for the reactor. This design bureau had designed the water
moderated reactors which were already providing power in Tashkent,
Riga, Kiev, Alma-Ata, Hungary, Rumania, DDR, Czechoslovakia, and Egypt.
Grabin was at that time developing the first experimental fast neutron
reactors using liquid metal cooling (SR-1 and SR-3) which were in
operation in Obninsk at the Physics-Energy Institute (FEI).

In the beginning, development and test work was oriented towards
providing power for an electric engine for manned interplanetary
flight. The nuclear electric engines for the initial TMK-E Mars
spacecraft design of 1960 used 7 MW of nuclear power. Later reactor
research was expanded to cover application of nuclear power for
scientific, economic, and military objectives in space.

OKB-1 and FEI studied various methods for transforming the reactor's
thermal energy to electrical energy to power the engine (steam
turbines, gas turbines, MHD, and direct thermo-electric conversion).
This analysis indicated that direct thermo-electric conversion was
clearly the best approach.

First stage testing of nuclear electric propulsion began in 1962 and
the original draft project N1 of that year foresaw the use of this form
of propulsion in multi-module orbital base stations and interplanetary
spacecraft. In 1965 Section 12 (Manager I I Raikov) of OKB-1 completed
work with FEI on a draft project for a nuclear electric propulsion
engine YaERD-2200 for interplanetary crewed spacecraft. The YaERD-2200
consisted of two independent stages. Each had a nuclear reactor and an
electric engine, with electrical output of each being 2,200 kW and
total thrust 8.3 kgf.

The engine featured direct thermo-electric conversion using a fast
neutron reactor; a coolant system using low activity isotope Lithium-7
in a single loop shared by both the reactor and engine; and an electro
plasma engine with an efficiency of 55% and a specific impulse of 5500
sec

The reactor / engine design was upgraded to 5,000 kW total power in
1966-1970. The revised design could be used in single block (YaE-1 and
YaE-1M) and multiple block (YaE-2 and YaE-3) applications. A single
Block YaE-1 would have an electrical output of 2,500-3,200 kW with fuel
for 4,000 to 8,000 hours of operation. Block YaE-1M would have an
output of 5000 kW. Total thrust of the engine would be from 6.2 to 9.5
kgf with a specific impulse of from 5,000 to 8,000 sec. In three block
applications, electric capacity would be 3 x 3,200 kW and 3 x 5,000 kW.
The Aelita MEK design of 1969 used a total of 15,000 kW.

Development of nuclear electric propulsion continued throughout the
1970's. In accordance with the decrees of 8 June 1971 and 15 June
1976 this was now concentrated on development of the more modest
nuclear electric rocket stage 11B97. This stage would have an electric
capacity of 500-600 kW and would use specialised plasma-ion electric
engines using standing plasma waves and anodes. In 1975 nuclear
electric propulsion work was reorganised within NPO Energia into a
special complex 7 (Manager M V Melnikov). In 1984 it was renamed
section 7 (Manager P I Bistrov, and from 1993 Y A Bakanov). Through all
these reorganisations functional test of the reactor and engine
components continued. Concepts for the direct thermoelectric
transformation of energy could not be realised without a new class of
refractory and high temperature materials, new heat pipe concepts, and
other new technology. To develop these technologies it was necessary to
build new materials test facilities, high temperature tests stands, new
experimental shops to develop methods to handle and work new refractory
alloys (niobium, molybdenum, wolfram, vanadium) and insulative and
magnetic materials.

From 1966 to 1982 many test stands were built to develop these
materials and test components of the systems. The final result was the
11B97 engine, powered from a reactor with a 200 litre core containing
30 kg of uranium fuel. In 1978 this engine was studied for use as a
reusable interorbital space tug for launch by Energia-Buran. In 1982,
according to the decree of 5 February 1981, NPO Energia developed for
the Ministry of Defence the interorbital tug Gerkules with 550 kW
maximum output and continuous operation in the 50-150 kW range for 3 to
5 years. In 1986 an interorbital tug was studied to solve the specific
application of transporting heavy satellites of 100 tonnes to
geostationary orbit, launched by Energia.

In 1986 RKK Energia updated the 1969 MEK design for launch by the new
Energia launch vehicle. The propulsion section was essentially the same
except that for safety reasons two completely independent redundant
reactor / engine assemblies were used in the place of the single unit
of the MEK design.

Energia retained the electric engines of the 1969 MEK design but
dropped the nuclear ractor for its 1989 Mars expedition design. This
spacecraft used the same thruster arrays requiring the same power
output (15 MW) as the 1986 nuclear design. But in this case two
enormous panels, each 200 m x 200 m would generate a total of 15 MW of
power at earth. The use of ultra-thin (less than 50 micrometer) / low
mass (0.2 kg per square meter) photovoltaic cells with a high specific
power value (up to 200 W per square meter) minimised the weight of
these vast arrays. The total mass of the electric engines, structure,
and solar panels was 40 tonnes. The power generated would be used
primarily by two ion engine clusters mounted perpendicular to the
living block. In high-power mode these would have a specific impulse of
3500 seconds. They would consume 165 tonnes of xenon propellant during
the voyage (of 355 tonnes total spacecraft mass).

In the 1990's Energia studied use of nuclear electric propulsion for
the scientific development project 'Mars - Nuclear electric propulsion
Stage' under contract to the Russian Space Agency and the project 'Star
- Soarer' under contract to the Ministry of Atomic Industry. These
studies looked at designs for the 2005 period. At the beginning of the
1990's a new type of nuclear generator was studied, that would have a
capacity of 150 kW in the transport role and provide 10-40 kW to power
spacecraft systems while coasting. This was designated ERTA
(Elecktro-Raketniy Transportniy Apparat). Technologies and concepts for
this engine were studied by FEI and other organisations. A modular
concept was adopted. In 1994 ERTA was studied for launch by Titan,
Ariane 5, or Energia-M launch vehicles. The reactor weight was 7,500 kg
and it could provide up to 10 years of electrical power traded off
against 1.5 years of powered flight.

Aside from this work on the 150 kW design, there was also an
examination at the same time of the use of nuclear electric propulsion
for Mars expeditions. Single and multiple launch approaches were
considered. For a single-launch complex of 150 tonnes a nuclear
electric propulsion unit of 5 to 10 MW with enough fuel for 1.5 years
would be required. For the multiple launch design, a power of 1 to 1.5
MW and fuel for three years would be required.

In 1994-95, RKK Energia, and NASA's Jet Propulsion Laboratory analysed
the project 'Mars Together'. This studied the use of spacecraft using
solar arrays or nuclear reactors of up to 30 to 40 kW for insertion
into Martian orbit and operation of a side-looking radar to digitally
map the surface. As a preliminary step a demonstration launch was
proposed of a spacecraft with a mass of 120 to 150 kg, a solar panel
area of 30 square meters and engines with a thrust of 3 kW. Objectives
of the experiment would be understanding of the changing of the orbital
altitude with continuous work of the ion engine for several hundred
hours. http://www.astronautix.com/articles/sovctric.htm

In article ,
Robert Kolker wrote:
...The one
resource that's a really good candidate for import from space is energy.

There is the Sun. We should use it.

Yep, and much the best way to do that is to convert the sunlight to
electricity in space, and beam it down as microwaves. Ground-based solar
would work well on an airless non-rotating planet, but is poorly suited
to large-scale use on Earth.
--
spsystems.net is temporarily off the air; | Henry Spencer
mail to henry at zoo.utoronto.ca instead. |

Matt Giwer wrote:
I haven't read all the responses so this may have been said.

The point of using nukes was the high specific impulse. That allows a high
final velocity like ion engines. Unlike ion engines they would not be calibrated
in milimouse-farts so the acceleration time is not an issue.


Most engine types either fail to give thrust or ISP effciency, as shown
in this chart
chart from Spacecraft Systems Engineering (second edition),

http://spacebombardment.blogspot.com...t-or-lazy.html

The proposed corrected version clearly shows that all the other charted
systems are unable to compete with Orion's combination of propellant
efficiency and power.

http://spacebombardment.blogspot.com...-is-orion.html

bombardmentforce wrote:
David Spain wrote:
Project Orion was a concept study.

And a test program. that lead into the Casaba Howitzer test program,
that was the secret core of Reagan's SDI.

http://spacebombardment.blogspot.com...r-concept.html

It proposed building a space-based
only "rocket" ...It was really only
seriously proposed for use strictly in space. The bombs were to be
released in a series of continuous distinct pulses.


Here's evidence it was seriously proposed for Earth launch, by a
serious player, who later was part of the team behind the World Trade
Center.

http://spacebombardment.blogspot.com...-re-lunar.html

In the long term some sort of tether/skyhook transfer system would be
used.

http://en.wikipedia.org/wiki/Space_e...ds.27_proposal

This could be quickly implimented using such a launch method, and that
limits the pollution to one or two major lift-off events.

Steve Hix wrote:

Politics stopped their use; until you can convince the Greenies that it
would be safe enough to put the (cold) engine in orbit before fueling
and lighting it off, we won't see any.

Politics quite possibly *would* have stopped the use of nuclear
engines, but they were stopped even earlier by the lack of a mission.
The main application for nuclear engines was manned exploration of the
solar system -- Mars missions, lunar shuttles and the like. When all
prospects of such missions evaporated, the real rationale for nuclear
engines vanished.

Thanks to the efforts of pro-NERVA Senator Anderson of New Mexico, the
original unmanned Grand Tour mission to the outer solar system was
killed. This kept alive a rationale for NERVA, namely its use to
propel unmanned spacecraft to the outer solar system in the absence of
planetary alignments suitable for slingshot assits. But that was a
flimsy excuse, and NERVA expired in 1973 along with Senator Anderson's
tenure in the Senate.

David Spain wrote:
Steve Hix wrote:

Politics stopped their use; until you can convince the Greenies that it
would be safe enough to put the (cold) engine in orbit before fueling
and lighting it off, we won't see any.

Putting the cold engines in orbit doesn't present a problem. It's putting up
the fuel. Since the days of Three Mile Island the words nuclear and irrational
have become synonymous in the English language.

I think what Steve Hix means by "cold" engine is one that's been fully
fueled with uranium but has never gone critical. The uranium fuel
itself, although somewhat enriched, is not highly radioacitve and is
not particularly dangerous. Once the reactor is started up for the
first time, however, many radioactive elements, which have short
half-lives and are therefore highly radioactive, are created. It is at
this point that the reactor becomes a hazard.

Of course, I don't expect that this fact will make the politics of
launching a nuclear engine much easier.

Henry Spencer wrote:

Yep, and much the best way to do that is to convert the sunlight to
electricity in space, and beam it down as microwaves. Ground-based solar
would work well on an airless non-rotating planet, but is poorly suited
to large-scale use on Earth.

For which we do not need a manned space program. Our unmanned programs,
by and large, have earned their keep. Not so, our manned programs. They
are kind of Pyramid Building.

Bob Kolker

wrote:
I think what Steve Hix means by "cold" engine is one that's been fully
fueled with uranium but has never gone critical. The uranium fuel
itself, although somewhat enriched, is not highly radioactive [sp] and is
not particularly dangerous. Once the reactor is started up for the
first time, however, many radioactive elements, which have short
half-lives and are therefore highly radioactive, are created. It is at
this point that the reactor becomes a hazard.


That I understand. However it would probably be easier to sell politically
if the reactor was shipped up first unfueled with the core fuel rods brought
up on separate flights, fueling the reactor while in Earth orbit.

Of course, I don't expect that this fact will make the politics of
launching a nuclear engine much easier.

Oh it will happen. It's just that manned space exploration is passing away
from the democracies that are too narcissistic to care.

Dave

wrote:
David Spain wrote:
Steve Hix wrote:

Politics stopped their use; until you can convince the Greenies that it
would be safe enough to put the (cold) engine in orbit before fueling
and lighting it off, we won't see any.

Putting the cold engines in orbit doesn't present a problem. It's putting up
the fuel. Since the days of Three Mile Island the words nuclear and irrational
have become synonymous in the English language.

I think what Steve Hix means by "cold" engine is one that's been fully
fueled with uranium but has never gone critical. The uranium fuel
itself, although somewhat enriched, is not highly radioacitve and is
not particularly dangerous. Once the reactor is started up for the
first time, however, many radioactive elements, which have short
half-lives and are therefore highly radioactive, are created. It is at
this point that the reactor becomes a hazard.

Of course, I don't expect that this fact will make the politics of
launching a nuclear engine much easier.

It may working its way into possibility, small step:


September 28, 2006

Nuclear fuel for Mars rover raises little concern

BY CHRIS KRIDLER
FLORIDA TODAY

A power generator that uses plutonium dioxide would give a 2009 Mars
rover more freedom to explore questions about life and water on the red
planet, NASA officials said in a hearing today.

In two sessions at the Florida Solar Energy Center on Wednesday, they
gave the public a chance to comment on a draft statement on the
potential dangers of a launch accident. The Mars Science Laboratory
would ride a Lockheed Martin Atlas 5 rocket from Cape Canaveral.

Less than a half percent of launches would have the potential to
release radiological material, they said.

"The risks from this mission would be low," said Mark Dahl, NASA
program executive for the mission.

They received only one comment during the afternoon session, from
engineering consultant John Martin of Indialantic.

"This thing seems to be super safe as far as actually releasing any
kind of radiation," he said. "I hardly see any possibility."

Engineers and scientists want to use the generator, instead of solar
power, so the roving laboratory can go to areas where there might be
less sunlight and more slopes to climb.

Otherwise, the mission would be limited to a narrow latitude band on
Mars.

"That certainly would limit us fairly significantly in being able to
pick a very scientifically interesting site," said project manager
Richard Cook of the Jet Propulsion Laboratory in California.

"I feel comfortable when we go through these kind of things," Brevard
County emergency management chief Bob Lay said. "I would not feel
comfortable if we didn't do this. This lets me see what kinds of
problems it might present for the county and then to look at those
kinds of problems and address those problems with some of the people
here that are leaders in this field in the nation."

The rovers now on Mars are about the size of golf carts. The Mars
Science Laboratory will be closer to Mini Cooper size, Cook said.

"It's just taking a step forward, not only scientifically, but
technically," Cook said.

It will include instruments that can identify chemicals that form the
basis of life.

"We want to understand if Mars has these chemicals present that life
seems to need and makes use of," said deputy project scientist Ashwin
Vasavada.

The craft would launch in fall 2009 and arrive at Mars in 10 to 12
months. It would be the first to use a Skycrane landing system, in
which a flying descent module lowers the rover to the surface with
wires.

The twin rovers, meanwhile, are still exploring, long after their early
2004 arrival at Mars. Wednesday, Opportunity made it to the highly
anticipated Victoria Crater after a nearly two-year quest.