Safe Affordable Fission Engine
Encyclopedia
Safe Affordable Fission Engine (SAFE) are NASA
's small experimental nuclear fission reactors for electricity production in space. Most known is the SAFE-400 reactor producing 400 kW thermal power, giving 100 kW of electric energy using a Brayton cycle
gas turbine. The fuel is uranium nitride
in a core of 381 pins clad with rhenium
. Three fuel pins surround a molybdenum
-sodium
heatpipe that transports the heat to a heatpipe-gas heat exchanger
. This is called a Heatpipe Power System. The reactor is about 50 centimetres (19.7 in) tall, 30 centimetres (11.8 in) across and weighs about 1200 kilograms (2,645.5 lb). It was developed at the Los Alamos National Laboratory
and the Marshall Space Flight Center
under the lead of Dave Poston. A smaller reactor called SAFE-30 was made first.
The project is funded with discretionary money in the lab's budget and done mostly outside the researchers' normal work.
NASA
The National Aeronautics and Space Administration is the agency of the United States government that is responsible for the nation's civilian space program and for aeronautics and aerospace research...
's small experimental nuclear fission reactors for electricity production in space. Most known is the SAFE-400 reactor producing 400 kW thermal power, giving 100 kW of electric energy using a Brayton cycle
Brayton cycle
The Brayton cycle is a thermodynamic cycle that describes the workings of the gas turbine engine, basis of the airbreathing jet engine and others. It is named after George Brayton , the American engineer who developed it, although it was originally proposed and patented by Englishman John Barber...
gas turbine. The fuel is uranium nitride
Uranium nitride
Uranium nitride refers to a family of several ceramic compounds: uranium mononitride , uranium sesquinitride , which exists in either an alpha or beta phase, and uranium dinitride ....
in a core of 381 pins clad with rhenium
Rhenium
Rhenium is a chemical element with the symbol Re and atomic number 75. It is a silvery-white, heavy, third-row transition metal in group 7 of the periodic table. With an average concentration of 1 part per billion , rhenium is one of the rarest elements in the Earth's crust. The free element has...
. Three fuel pins surround a molybdenum
Molybdenum
Molybdenum , is a Group 6 chemical element with the symbol Mo and atomic number 42. The name is from Neo-Latin Molybdaenum, from Ancient Greek , meaning lead, itself proposed as a loanword from Anatolian Luvian and Lydian languages, since its ores were confused with lead ores...
-sodium
Sodium
Sodium is a chemical element with the symbol Na and atomic number 11. It is a soft, silvery-white, highly reactive metal and is a member of the alkali metals; its only stable isotope is 23Na. It is an abundant element that exists in numerous minerals, most commonly as sodium chloride...
heatpipe that transports the heat to a heatpipe-gas heat exchanger
Heat exchanger
A heat exchanger is a piece of equipment built for efficient heat transfer from one medium to another. The media may be separated by a solid wall, so that they never mix, or they may be in direct contact...
. This is called a Heatpipe Power System. The reactor is about 50 centimetres (19.7 in) tall, 30 centimetres (11.8 in) across and weighs about 1200 kilograms (2,645.5 lb). It was developed at the Los Alamos National Laboratory
Los Alamos National Laboratory
Los Alamos National Laboratory is a United States Department of Energy national laboratory, managed and operated by Los Alamos National Security , located in Los Alamos, New Mexico...
and the Marshall Space Flight Center
Marshall Space Flight Center
The George C. Marshall Space Flight Center is the U.S. government's civilian rocketry and spacecraft propulsion research center. The largest center of NASA, MSFC's first mission was developing the Saturn launch vehicles for the Apollo moon program...
under the lead of Dave Poston. A smaller reactor called SAFE-30 was made first.
The project is funded with discretionary money in the lab's budget and done mostly outside the researchers' normal work.
See also
- Systems Nuclear Auxiliary Power ProgramSystems Nuclear Auxiliary Power ProgramThe Systems Nuclear Auxiliary Power program was a program of experimental radioisotope thermoelectric generators and space nuclear reactors flown during the 1960s by NASA.-Odd-numbered SNAPs: radioisotope thermoelectric generators:...
and SNAP-10ASNAP-10ASNAP-10A was the first and so far only known launch of a U.S. nuclear reactor into space . The Systems Nuclear Auxiliary Power Program reactor was developed under the SNAPSHOT program overseen by the U.S...
, that flew in 1965 - SP-100SP-100SP-100 was a U.S. research program for nuclear fission reactors in space. It was started in 1983 by NASA, the US Department of Energy and other agencies. It developed a reactor with heat pipes transporting the heat to thermionic converters...