Posted on 01/30/2015 9:14:11 AM PST by BenLurkin
Although no nuclear-thermal engines have ever flown, several design concepts have been built and tested over the past few decades, and numerous concepts have been proposed. These have ranged from the traditional solid-core design to more advanced and efficient concepts that rely on either a liquid or a gas core.
In the case of a solid-core design, the only type that has ever been built, a reactor made from materials with a very high melting point houses a collection of solid uranium rods which undergo controlled fission. The hydrogen fuel is contained in a separate tank and then passes through tubes around the reactor, gaining heat and converted into plasma before being channeled through the nozzles to achieve thrust.
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Many of these problems were addressed with the liquid core design, where nuclear fuel is mixed into the liquid hydrogen and allowing the fission reaction to take place in the liquid mixture itself. This design can operate at temperatures above the melting point of the nuclear fuel thanks to the fact that the container wall is actively cooled by the liquid hydrogen. It is also expected to deliver a specific impulse performance of 1300 to 1500 (1.3 to 1.5 kN·s/kg) seconds.
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The final classification is the gas-core engine, a modification of the liquid-core design that uses rapid circulation to create a ring-shaped pocket of gaseous uranium fuel in the middle of the reactor that is surrounded by liquid hydrogen. In this case, the hydrogen fuel does not touch the reactor wall, so temperatures can be kept below the melting point of the materials used.
(Excerpt) Read more at universetoday.com ...
It was even successfully tested using conventional explosives here on earth.
I’d still like to hear more from DARPA on their fusion research. I generally write people off when they say fusion but when DARPA says it I listen.
These three proposals are all fission engines where the nuclear fuel serves only to heat a liquid propellant into high energy jets of plasma.
Fission reactors could also be used to power VASMIR engines at a much higher energy rate than have been tested so far.
in before Star Trek reference....
The first thing we need to do before this is build the next generation of telescopes. These will be so powerful that we can decide where to go before we leave.
The next generation of telescopes are being built all the time. We still need much better propulsion systems to effectively explore our own solar system.
Well, that was very funny. And clever. In before the Uranus jokes.
Well I’m working on a circumcision joke for Jew Peter.
Well if you can’t hack it.....
So I guess they`ve forgotten about the Challenger, what happens when one of these blows up during launch?
OH! ..I really love ‘em (just revealing my PC mode)
You put a nuke drive in orbit with a standard chemical rocket. Load the fuel and coolant, then fire it up. NASA and the AEC ran the NERVA program testing solid core nuclear rockets until the early 1970’s. They tested a design that was almost ready to put in orbit and test.
The primary consideration should be to develop an electro-magnetic type of shielding to protect the ship and its human crew from the effects of cosmic radiation from our Sun and other sources. An emulation of what protects the Earth would be a good start.
Without that, the type of propulsion is immaterial if the crew is killed or severely effected by the hostile environment they travel through for extended periods.
As a fan of silver age Marvel comics, getting belted by cosmic rays has its benefits.
Correct, yes I got that, but what was powering the space shuttle Challenger when it blew up? Chemical rockets? I`ve seen footage of many a rocket blowing up on launch, so what happens when one of these blows up during it`s chemical launch phase?
Definitely. But I have a hard time choosing. Invisibility with force field projection capabilities? Or the ability to stretch/deform any part of your body to limitless size/length? There are others but still hard to decide.
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