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China Builds World's Fastest Hypersonic Wind Tunnel To Simulate Flight At 27,000 MPH (scmp.com)

Posted by BeauHD on from the wind-breaker dept.

schwit1 quotes a report from South China Morning Post: China is building the world's fastest wind tunnel to simulate hypersonic flight at speeds of up to 12 kilometers per second (~27,000 miles per hour). Zhao Wei, a senior scientist working on the project, said researchers aimed to have the facility up and running by around 2020 to meet the pressing demand of China's hypersonic weapon development program. "It will boost the engineering application of hypersonic technology, mostly in military sectors, by duplicating the environment of extreme hypersonic flights, so problems can be discovered and solved on the ground," said Zhao. The world's most powerful wind tunnel at present is America's LENX-X facility in Buffalo, New York state, which operates at speeds of up to 10 kilometers per second -- 30 times the speed of sound. Hypersonic aircraft are defined as vehicles that travel at speeds of Mach 5, five times the speed of sound, or above.

In the new tunnel there will be a test chamber with room for relatively large aircraft models with a wing span of almost three meters. To generate an airflow at extremely high speeds, the researchers will detonate several tubes containing a mixture of oxygen, hydrogen and nitrogen gases to create a series of explosions that can discharge one gigawatt of power within a split second, according to Zhao. The shock waves, channelled into the test chamber through a metallic tunnel, will envelope the prototype vehicle and increase the temperature over its body to 8,000 Kelvins, or 7,727 degrees Celsius, Zhao said. The new tunnel would also be used to test the scramjet, a new type of jet engine designed specifically for hypersonic flights. Traditional jet engines are not capable of handling air flows at such speeds.

43 of 63 comments (clear)

  1. Strike by Anonymous Coward · · Score: 1

    Anywhere in the world in under 30 mins. Not bad.

    1. Re:Strike by ClickOnThis · · Score: 4, Insightful

      Low earth-orbit velocity is about 17,500 mi/hr. Escape velocity is about 25,000 mi/hr. They're testing at speeds above the earth's escape velocity.

      Yes, anywhere in the world in under 30 min, but you'd need to burn lots of fuel not just to fly that fast, but also to keep yourself following the curvature of the earth, so you don't fly out into space and never come back..

      --
      If it weren't for deadlines, nothing would be late.
    2. Re:Strike by AbRASiON · · Score: 2

      Offtopic but it *blows my mind* that escape velocity is that god damn fast *AND* we can do it. I just googled it, it's 7 miles a SECOND. That's astronomically fast (duh)

      It's so insanely ridiculously quick, I can't fathom how the rockets can even do it, with people strapped to the front. The forces involved, the heat, the strain, the G's it's ... wow it's truly insane.

    3. Re:Strike by currently_awake · · Score: 1

      An explosive driven wind tunnel is optimized for testing bullets not aircraft. It can't maintain flight speed long enough to test a scram jet engine in flight, and the China wind tunnel is too small to test a manned aircraft.

    4. Re:Strike by Anonymous Coward · · Score: 1

      Offtopic but it *blows my mind* that escape velocity is that god damn fast *AND* we can do it. I just googled it, it's 7 miles a SECOND. That's astronomically fast (duh)

      It's so insanely ridiculously quick, I can't fathom how the rockets can even do it, with people strapped to the front. The forces involved, the heat, the strain, the G's it's ... wow it's truly insane.

      Here you are a g-force calculator have fun.

      Keep in mind that a fit person can handle about 5g's although it would be very uncomfortable. In the calculator, if you enter "0" for your start and "25,000 mph" as your finish speed then enter say 5g as the "g-force" it would take about six minutes and 20 seconds to reach 25,000 mph usually that would kill or maim most people unless they were very fit or had protective clothing.

      An interesting read on heavy acceleration . There are plenty of articles on this.

  2. Building by DumbSwede · · Score: 2

    Shouldn't it be Building not Builds. It won't be completed until 2020.

    --
    Letter To Iran
    1. Re:Building by thegarbz · · Score: 1

      Better still, it shouldn't be "wind tunnel" but "shock tunnel"

  3. Not very realistic for transportation by dlleigh · · Score: 5, Informative

    Low Earth orbital velocity is a little under 8 km/sec, so if you're moving faster than that, you're going to be spending a lot of fuel trying to stay down, close to the Earth. In other words, much of your thrust will be needed to add extra centripetal acceleration to supplement the pull of gravity. Earth escape velocity is about 11.2 km/sec, so moving anywhere at 12 km/sec would put you at risk of never coming home again if something went wrong with your vehicle. The amount of energy required to move at these speeds is huge, and would require tremendous amounts of fuel to achieve: note the size of a rocket necessary to accelerate a satellite up to orbital velocity. This hypersonic research is weapons related. The researchers are undoubtedly interested only in small payloads going at these speeds for very brief periods of time. One application might be getting a small warhead past a warship's defenses. Another application might be ICBM reentry.

    1. Re:Not very realistic for transportation by Strider- · · Score: 4, Informative

      Well, the other bit to consider is that when you're testing scale models in a wind tunnel, depending on what you're testing you also need to scale the wind/air conditions to achieve accurate results. Often this means scaling up the airspeed and/or air pressure as you scale down the object being tested.

      Let's say I'm testing out a new design for an airliner wing. At full scale, the air flowing over it will exert a certain amount of force per area (PSI or Newtons/m^2, take your pick). Now, since it's not practical to put a full sized airliner wing into a wind tunnel, I build a 1/4 scale model, and put that in the wind tunnel. Here's the rub: if I ran the air over my 1/4 scale model at the same conditions as I were to test the full sized wing, I would be applying 1/16th the scale force. To make up for the difference, I need to either scale up the airspeed, the air pressure, or both. There are also a whole host of other weird effects that need to be taken into account.

      Anyhow, it's not just that this thing is designed to test a vehicle/weapon capable of operating at 27,000mph, but rather that it can provide realistic conditions to a scale model of the craft under test.

      --
      ...si hoc legere nimium eruditionis habes...
    2. Re:Not very realistic for transportation by rmdingler · · Score: 1

      Many thanks to the Parent and the Grandparent... I'll likely be red-eyed tomorrow driving to the deer lease after spending way too much time reaearching orbital velocity conundrums and scale model wind tunnels.

      --
      Happiness in intelligent people is the rarest thing I know.

      Ernest Hemingway

    3. Re:Not very realistic for transportation by phantomfive · · Score: 1

      Did you learn anything interesting worth reporting on?

      --
      "First they came for the slanderers and i said nothing."
    4. Re:Not very realistic for transportation by rmdingler · · Score: 1

      Did you learn anything interesting worth reporting on?

      Two things so far:

      Some of the posters on here are way too f*cking smart.

      Get started reading Slashdot at your own peril when you really need a good night's sleep.

      --
      Happiness in intelligent people is the rarest thing I know.

      Ernest Hemingway

    5. Re:Not very realistic for transportation by phantomfive · · Score: 1
      Some of the posters on here are way too f*cking smart.

      Well that definitely includes you. A smart person is just someone who says something you don't know.

      --
      "First they came for the slanderers and i said nothing."
    6. Re:Not very realistic for transportation by rmdingler · · Score: 1

      A smart person is just someone who says something you don't know.

      Well said.

      Here's one I came across googling like a drooling idiot/imbecile/moron:

      Escape velocity reduces as you get further away from the Earth. If you proceed upwards at a constant speed of 1 mph (which as noted will require continuous thrust to counteract gravity), you will eventually reach a distance where the escape velocity is equal to 1 mph. Then, you will have reached escape velocity and are no longer gravitationally bound to the Earth.

      --
      Happiness in intelligent people is the rarest thing I know.

      Ernest Hemingway

    7. Re:Not very realistic for transportation by viperidaenz · · Score: 2

      If you have a projectile going at mach 30, you don't need a warhead to destroy a warship. You just need to hit it.
      Every kilogram of mass in the projectile carries the energy of 0.017 kilotons at 12 kilometres per second.
      You'd need only 820kg to match the bomb dropped on Hiroshima.

    8. Re:Not very realistic for transportation by darkshadow · · Score: 1

      Starflight: The Plane That Couldn't Land (1983)
      http://www.imdb.com/title/tt00...

      --
      -Darkshadow (There was a thing called Heaven; but all the same they used to drink enormous quantities of alcohol.)
  4. Worlds fastest? by PPH · · Score: 1

    That's still Operation Plumbbob

    --
    Have gnu, will travel.
    1. Re:Worlds fastest? by serviscope_minor · · Score: 1

      In fairness, they never intended to measure the speed of the end cap.

      However, NASA has built wind tunnles of a sort, capable of 60,000 m/s for a very short time for experiments on reentry on Jupiter. Fnu read:

      https://history.nasa.gov/SP-44...

      --
      SJW n. One who posts facts.
    2. Re:Worlds fastest? by Hal_Porter · · Score: 1

      http://nuclearweaponarchive.or...

      Learning to Contain Underground Nuclear Explosions

      By Dr. Robert R. Brownlee

      June 2002

      Sometime in 1956 Dr. Alvin Graves, Division Leader of the Test Division at Los Alamos told me that we were going to have to test underground in order to reduce fallout as much as possible. He asked me to see what I could learn about it by making what calculations I could.

      The temperatures and pressures generated by a nuclear explosion are such that there was considerable doubt that any underground test buried at a "reasonable" depth could be contained.

      In 1956 we were severely limited in computing capabilities-compared to nowadays they were laughable, and miniscule, and arguably nonexistent. I had the equations of state of four materials. They were air and water, aluminum and uranium. As it happens, there is a lot of aluminum in NTS soil, so I called that "earth". I called that of uranium "fire", and the others were air and water, so with earth, air, fire and water, how could I fail?

      In attempting to mock up the earth, I had some information about NTS soil densities and water content. I used a cylindrical pipe filled with air of several densities, depending upon the possible use of vacuums. I was allowed considerable freedom to choose other parameters as I wished. For example, what might the efficacy of plugs of various masses be, and where might they be placed for optimum results. I worked regularly with Bill Ogle, the deputy division leader, and we decided to have a first test in an "empty" pipe (cables were present), open at the top. Then we would do a test with a cap, and then do tests with plugs, the first one used to be in the middle of the hole, and the second one at the bottom. Thus we hoped to learn from test to test, acquiring data and information incrementally. Incidentally, the Pascal B test, and those immediately following, had a 4-foot diameter pipe. The cap welded to the top of Pascal B was four inches thick, so was of appreciable mass from a "man-handling" point of view.

      The first test of our "series" was Pascal A, with results as documented.

      For Pascal B, my calculations were designed to calculate the time and specifics of the shock wave as it reached the cap. I used yields both expected and exaggerated in my calculations, but significant ones. When I described my results to Bill Ogle, the conversation went something like this.

      Ogle: "What time does the shock arrive at the top of the pipe?"
      RRB: "Thirty one milliseconds."
      Ogle: "And what happens?"
      RRB: "The shock reflects back down the hole, but the pressures and temperatures are such that the welded cap is bound to come off the hole."
      Ogle: "How fast does it go?"
      RRB: "My calculations are irrelevant on this point. They are only valid in speaking of the shock reflection."
      Ogle: "How fast did it go?"
      RRB: "Those numbers are meaningless. I have only a vacuum above the cap. No air, no gravity, no real material strengths in the iron cap. Effectively the cap is just loose, traveling through meaningless space."
      Ogle: And how fast is it going?"

      This last question was more of a shout. Bill liked to have a direct answer to each one of his questions.

      RRB: "Six times the escape velocity from the earth."

      Bill was quite delighted with the answer, for he had never before heard a velocity given in terms of the escape velocity from the earth! There was much laughter, and the legend was now born, for Bill loved to report to anybody who cared to listen about Brownlee's units of velocity. He says the cap would escape the earth. (But of course we did not believe that would ever happen.)

      The next obvious decision was made. We'll put a high-speed movie camera looking at the cap, and see if we can measure the departure velocity.

      In the event, the cap appeared above the hole in one frame only, so there was no direct velocity measurement. A lower limit c

      --
      echo -e 'global _start\n _start:\n mov eax, 2\n int 80h\n jmp _start' > a.asm; nasm a.asm -f elf; ld a.o -o a;
  5. They should hire me by Snotnose · · Score: 1

    and feed me Taco Bell. Every 2-3 minutes they'll get a blast of hot air that should meet their requirements.

    1. Re:They should hire me by UnknownSoldier · · Score: 1

      Winds Of Malodor Discharges ?
      Whiffs Odeaus Mephitis Drafts ?

      Who knew flatulence was considered a weapon! :-)

  6. Re:First? by boudie2 · · Score: 1

    Don't sugar coat it, it's commie propaganda. We got shit they don't even know about. Hell, we got stuff we don't even know about.

  7. Re:First? by OldMugwump · · Score: 1

    Propaganda, maybe. But not commie propaganda. The Chinese are capitalists.

    --
    "Shoot, a fella could have a pretty good weekend in Vegas with all that stuff."
  8. Re:First? by Strider- · · Score: 5, Interesting

    Supersonic/Hypersonic wind tunnels are tremendously expensive and power hungry. There's pretty much no way to hide them. Yeah, there might be small scale versions out there (say the hypersonic helium gas guns etc...) but we're talking really small scale. This kind of testing is why NASA was given/assigned an SR-71; they could use the drone attachment points to carry tests and essentially use the atmosphere as a high super-sonic wind tunnel. Look at the pictures of the NASA SR-71 carrying the linear aerospike engine during testing.

    --
    ...si hoc legere nimium eruditionis habes...
  9. A GW of power within a split-second? by haruchai · · Score: 1

    I see we're confusing power & energy.....again

    --
    Pain is merely failure leaving the body
    1. Re:A GW of power within a split-second? by Anonymous Coward · · Score: 1

      It's actually 1.21 GW.

  10. Re:First? by boudie2 · · Score: 1

    When the Communist Party of China starts calling themselves the Capitalist Party of China I'll agree with you.

  11. Units by Anonymous Coward · · Score: 1

    How hard would it have been for the author to present the entire article in a common unit of measure. US version is 10km/s and the China version is 12km/s in two years.

  12. It wouldn't work the way you're envisioning. by hey! · · Score: 2

    The US has had a hypersonic weapon program for years -- called Prompt Global Strike. The idea wouldn't necessarily be to fly all the way around the world in the atmosphere; there are several delivery modes envisioned, one of which is to launch the vehicle on an ICBM; it would then re-enter the atmosphere in controlled, hypersonic flight, evading any terminal phase missile defenses like Russia's S-400.

    However there are treaty limits on ballistic missiles (regardless of their payload), and a ballistic missile launch risks triggering early warning systems in Russia and China. So I think a submarine or airplane launched system is more likely to happen. This would provide the same "anywhere in the world in 30 minutes" capability without necessarily even being detected.

    --
    Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
    1. Re:It wouldn't work the way you're envisioning. by currently_awake · · Score: 2

      Hypersonic isn't stealthy. Your wake reflects radar (ionization) and sends seismic shock waves into the ground (at low altitude) that show where you are. The biggest problem with fast missiles is detecting the target at that speed. Even weak radar jamming or chaff could render your missile blind long enough to miss, and at that speed you don't have time or fuel to turn around and try again.

    2. Re:It wouldn't work the way you're envisioning. by Hal_Porter · · Score: 1

      Didn't ICBMs use variations in gravity? Or at least they're rumoured to - I don't think anyone would confirm something like that.

      https://books.google.com/books...

      --
      echo -e 'global _start\n _start:\n mov eax, 2\n int 80h\n jmp _start' > a.asm; nasm a.asm -f elf; ld a.o -o a;
    3. Re:It wouldn't work the way you're envisioning. by AmiMoJo · · Score: 1

      Hypersonic missiles don't use radar for targeting. They are programmed with fixed target coordinates, and most have some capability to be updated mid-flight. For moving targets like ships they rely on secondary systems like satellites and spotter aircraft, and several missiles are fired into the projected path.

      At the kinds of speeds they travel any terminal guidance is pretty limited, not least by the effective range of radar and optical systems.

      --
      const int one = 65536; (Silvermoon, Texture.cs)
      SJW, n: "Someone I don't like, and by the way I'm a fuckwit" - AC
    4. Re:It wouldn't work the way you're envisioning. by dlleigh · · Score: 1

      I don't know what they use in the real world, but I doubt they try to measure gravity. You can make gravitational maps of the Earth from an orbiting spacecraft, but that takes many many orbits and careful measurement of those orbits from the ground. An ICBM in flight simply wouldn't have the time to make such a map, and I doubt it would be communicating with ground stations either.

      The Earth is "lumpy" from a gravitational perspective so it's plausible that a highly accurate ICBM might need to take precise gravitational maps into account. However, those maps would have to be created ahead of time and pre-programmed into the missile.

      Scientists have created gravitational maps of the Earth and the moon, as well as other solar system bodies.

    5. Re:It wouldn't work the way you're envisioning. by Hal_Porter · · Score: 1

      I think the idea is that you build a gravity variation map slowly using a satellite. Then you download that map into your ICBM which uses it to navigate.

      --
      echo -e 'global _start\n _start:\n mov eax, 2\n int 80h\n jmp _start' > a.asm; nasm a.asm -f elf; ld a.o -o a;
  13. Scramjet... not new by YVRGeek · · Score: 1

    FTA: "The new tunnel would also be used to test the scramjet, a new type of jet engine"... So not new; scramjets have been built on an experimental basis since the early 1950's: https://en.wikipedia.org/wiki/... Wish people would edit their articles more carefully. What *is* new is that scramjets are finally becoming a practical reality and _that's_ very interesting.

  14. 7,727 degrees Celsius by thinkwaitfast · · Score: 1

    I wonder how they achieve such accuracy.

  15. Re:First? by Hal_Porter · · Score: 1

    So they flew a linear aerospike on an SR-71? Interesting.

    https://www.nasa.gov/centers/d...

    --
    echo -e 'global _start\n _start:\n mov eax, 2\n int 80h\n jmp _start' > a.asm; nasm a.asm -f elf; ld a.o -o a;
  16. Why? by bytesex · · Score: 1

    Other than for reentry space vehicles - why would you, if you wanted to go at speeds like that, still travel inside our atmosphere?

    --
    Religion is what happens when nature strikes and groupthink goes wrong.
  17. Re:First? by dunkelfalke · · Score: 1

    So that makes North Korea a democracy then?

    --
    "It's such a fine line between stupid and clever" -- David St. Hubbins, Spinal Tap
  18. Re:First? by boudie2 · · Score: 1

    Well played. While I agree China is not really communism since you don't even get free health care. Then again they don't vote and have very limited freedom. There are markets but much of the money goes to the state. It's more of an abomination than anything. Would you want to live there? I know I wouldn't. And if I want to call them communists it's close enough.

  19. 7700 C by newslash.formatblows · · Score: 1

    What exactly can you heat to 7700 C without it melting and/or vaporizing?

  20. Re:First? by dunkelfalke · · Score: 1

    There is nothing about China that is communist in any way. What they have nowadays is state capitalism bordering on fascism.

    And as for "would you want to live there", what does have this anything to do with them being or not being communists? I wouldn't want to live in all kinds of countries.

    --
    "It's such a fine line between stupid and clever" -- David St. Hubbins, Spinal Tap
  21. Re:First? by boudie2 · · Score: 1

    "There is nothing about China that is communist in any way."
    If you told that to a dead horse, he'd get up and kick you in the head.