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Thread: VASIMR: Variable Specific Impulse Magnetoplasma Rocket

  1. #1
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    VASIMR: Variable Specific Impulse Magnetoplasma Rocket

    VASIMR coming out of the black after 2+ years of work...

    1627085788131.jpg

    VASIMR VX-200SS Plasma Rocket Completes Record 88-hour High-power Endurance Test

    WEBSTER, Texas (Ad Astra Rocket Co. PR) — Ad Astra Rocket Company’s VASIMR® VX-200SS Plasma Rocket has completed 88 hours of continuous operation at 80 kW at the company’s Texas laboratory near Houston. In doing so, the company establishes a new high-power world endurance record in electric propulsion. The test also demonstrates the maturity of the VASIMR® engine technology as a competitive option for high-power in-space electric propulsion with either solar or nuclear electric power. Electric rockets operating above 50 kW/thruster are considered “high-power.”

    The test began at 12:50 pm (CST) last Monday July 12 and ended Friday, July 16 at 4:55 am (CST). The firing stopped only 12 hours shy of its intended duration of 100 hours due to a spurious temperature sensor located in the test support equipment and not on the rocket structure. The rocket, however, was performing normally and all indications were that, were it not for this faulty sensor, it would have met and exceeded the 100- hour goal. Ad Astra believes the 88-hr test provides objective and sufficient evidence that the VASIMR® engine has met the intent of the high-power endurance goal set by NASA.

    “The test is a major success, the culmination of years of trial-and-error testing and painstaking attention to detail and a handsome reward for the team’s tenacity and dedication,” said Franklin R. Chang Díaz, Ad Astra’s chairman and CEO and a decorated former NASA astronaut. “With a new set of engine modifications already in the manufacturing stage, we’ll now move to demonstrate thermal steady state at 100 kW in the second half of 2021,” he added.

    The VASIMR® engine is unique in that it retains the high power of a chemical rocket but with ten times the fuel efficiency. As such, it is an excellent candidate for a host of applications, ranging from high-payload solar-electric robotic commercial cargo and resupply missions in cis-lunar space, to fast human missions to Mars and beyond with nuclear-electric propulsion (NEP).

    The growing importance of NEP missions for which VASIMR® is ideally suited is reflected in the language of the 2022 Bill submitted by the Committee on Appropriations for Commerce, Justice, Science and Related Agencies of the US House of Representatives, which states that “…at least $10,000,000 shall be utilized to begin a systematic approach to Nuclear Electric Propulsion…”, and “Within 180 days of the enactment of this Act, NASA, in coordination with other relevant Federal departments and agencies such as the Department of Energy, shall submit a multi-year plan for in-space propulsion-system demonstration for NEP.”

    “It is absolutely inspiring to see how much Franklin Chang Díaz and the Ad Astra team have been able to accomplish and advance in the years that I have known them. This technology has major potential to revolutionize the space industry,” said U.S. Congressman Brian Babin, Ranking Member of the House Space and Aeronautics Subcommittee. “Ad Astra’s small but dedicated team is a true testament of perseverance and continuing to invest in advanced technologies such as VASIMR® is critical if we want to remain a country that leads in space exploration,” he added.

    The company’s main goal is for the VASIMR® engine to demonstrate thermal steady-state operation at increasingly higher power levels. This condition calls for all the temperatures of the engine’s critical components to be stably maintained by the engine’s thermal management system.

    “The ability to operate continuously at 80 kW is exciting because we are so close to our 100-kW design goal and needing to focus on upgrading just a few components,” said Dr. Matthew Giambusso, Ad Astra Senior Research Scientist, and leader of experiment operations. “The rapid sequence of successful tests of the last few weeks have been thrilling,” he added.

    Major advances in the design of this system have been achieved in experimental campaigns lasting days to weeks, each followed by a period of inspection, disassembly, and improvement. This rapid prototyping is the basis for Ad Astra’s approach to mature the VASIMR® technology quickly and provide a competitive high-power electric propulsion option for both public and private customers.

    The thermal management of the VASIMR® engine is uniquely challenging, as temperatures from millions of degrees in the rocket’s plasma core to near absolute zero in the superconducting magnet, located a few tens of centimeters away, must be carefully controlled. This, of course, in the vacuum environment where the engine must operate. These stringent requirements have required Ad Astra to develop innovative manufacturing and assembly techniques to meet unusual thermal and electromagnetic constraints within the available engine envelope. “Getting the great diversity of materials to work in harmony in the environment we subject the engine to has presented major manufacturing challenges we have had to overcome,” said Mr. Lawrence “DJ” Dean, Ad Astra’s head of manufacturing.

    About the technology: Short for Variable Specific Impulse Magnetoplasma Rocket, VASIMR® works with plasma, an electrically charged gas, heated to extreme temperatures by radio frequency (RF) waves, and controlled and guided by strong magnetic fields, which also provide insulation. Plasma rockets, such as VASIMR®, have an extremely low fuel consumption and much higher power and/or performance as compared to other electric or chemical rockets. VASIMR® offers economic and operational advantages in satellite deployment, re-boost, refurbishment, and end-of-life disposal. With the proper nuclear-electric power source, VASIMR® could enable much faster and safer human and robotic transportation in deep-space where solar power is insufficient.

  2. #2
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    Looks good. I’m glad to see they aren’t hiding power requirements (I’ve seen popular press articles discussing high thrust electric propulsion such as VASIMR that never get around to mentioning that high thrust, high velocity exhaust means prodigious power requirements, so large solar arrays or good sized reactors are required). I like the company name too (Ad Astra).

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  3. #3
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    Thanks Docmordrid.

    Potentially the most interesting new thread this year.

    I am still getting my ahead around the implications of the technology and how it works.

    This is what politico had to say in its article on the rocket engine that could transform space travel

    Why it could be a game-changer: Ad Astra was the only one of the three companies awarded NASA contracts in 2015 under the NextSTEP public-private partnership that is still in the running. If it can successfully complete the engineering phase, Chang-Diaz maintains, the engine could fuel a “total transformation of the transportation scheme.”

    “We can see missions to Mars that could be two to three months one way and even faster than that as the technology progresses,” he explained, compared to “seven to eight months and maybe even longer. It would completely transform the way transportation is done.”

    That also means “moving stuff from low-Earth orbit to the vicinity of the moon, picking up trash, repositioning satellites, transporting supplies, essentially supporting a logistics traffic system,” he said.

    As for human space travel? “Less radiation, less consumables, everything is better,” Chang-Diaz said. A nuclear-electric engine would also mean spacefarers could more easily turn back or change course if needed, unlike traditional spacecraft, which are essentially designed to coast to their destination. “When you have a rocket like ours, you are really thrusting all the time,” Chang-Diaz said.

  4. #4
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    Quote Originally Posted by DavidLondon View Post
    This is what politico had to say in its article on the rocket engine that could transform space travel
    It also mentioned the next challenge for the technology:

    ….What’s his biggest worry? Right now it’s not whether the engine will work; “it’s almost boring to watch,” he said. It’s whether the company’s facility can survive the test. “The vacuum requirements are extreme. It’s putting a lot of exhaust into a chamber. You have to remove it,” he said. “The electricity we have to feed into the facility is very expensive. The facility is the challenge, at least now. Maybe a year ago I would have said the rocket was the challenge. Now the facility is the challenge.”

  5. #5
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    DavdLondon, it barely touches on VASIMR, but you might like this article in Nature on electric propulsion:

    https://www.nature.com/articles/s41467-017-02269-7

    Recently, low power electric thrusters have become widely used for orbit correction in new satellites, and is starting to be used in long duration interplanetary missions (Dawn mission). Then there is the use on miniature spacecraft like cubesats. Space engineering, by the traditional aerospace firms at least, has been very conservative so it took a long time for this to happen, but by not needing so much reaction mass, it can dramatically increase satellite lifespan or reduce satellite mass.

    There are different approaches to high power electric propulsion, VASIMR is just one of them. That is likely to become most important for the asteroid belt and outer system, where travel time would become especially long. Remember, high power electric propulsion requires large solar arrays or high power nuclear reactors.

    One other issue is the reaction mass for electric propulsion. Xenon is generally preferred now, but there is only a trace in Earth’s atmosphere so it is expensive to collect and probably not suitable if a lot of reaction mass is needed. Argon is somewhat less preferable, but is much more common and much less expensive. SpaceX is using argon for Starlink. In the future, argon could also be collected on Mars (a bit under 2% of the atmosphere) and on Venus (presumably collected from aerostats).

    Other chemicals could also be used as reaction mass, but noble gasses have an advantage in not being chemically reactive. Other chemicals would cause more wear, perhaps a lot more wear.

    "The problem with quotes on the Internet is that it is hard to verify their authenticity." — Abraham Lincoln

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  6. #6
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    SpaceX is using argon for Starlink
    This is incorrect, Starlink's Hall effect thrusters use Krypton.

    Elon Musk ✓ @elonmusk
    Krypton thrusters operative, satellites initiating orbit raise every 90 mins

    https://twitter.com/elonmusk/status/1132078782217539584

    https://www.businessinsider.com/elon...k-weird-2019-5

    Musk said each Starlink would then boot up and begin firing its Hall thruster, or ion engine. The engines will shoot out krypton gas ions to slowly yet very efficiently fly from 273 miles (440 kilometers) to 342 miles (550 kilometers) above Earth.

  7. #7
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    Oh, whups, thanks for the correction. I read a tweet awhile back and I thought he said argon when he mentioned the cost issue. Ah, well.

    "The problem with quotes on the Internet is that it is hard to verify their authenticity." — Abraham Lincoln

    I say there is an invisible elf in my backyard. How do you prove that I am wrong?

    The Leif Ericson Cruiser

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