Hyperloop LA Tunnel will Open on December 10

Discussion in 'HardForum Tech News' started by AlphaAtlas, Oct 23, 2018.

  1. sfsuphysics

    sfsuphysics I don't get it

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    Well the tunnel is less than 2 miles long , if you accelerate at a blistering 1g for half the trip (other half is decelerating at 1g) you will only get to just over 300 mph.
     
  2. viper1152012

    viper1152012 [H]ard|Gawd

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    My bad, I forgot we were off topic and comparing it to other countries.

    I suppose anything can rain on a parade.

    I for one am excited.

    But hey, if you don't want boring because its not the fastest cool. Guess we can rain on google fiber because its not the fastest either.

    Love getting a wiki lesson.
     
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  3. kju1

    kju1 2[H]4U

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    So what? Is there a train line right above the tunnel you can take instead? Are there any train lines going where this tunnel goes?
     
  4. Inglix_the_Mad

    Inglix_the_Mad Limp Gawd

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    Listen, I like Elon much of the time.

    Tesla cars are a wonderful application of current technology into a nicer package. He didn't really make anything "new" per se in a revolutionary sense - technologically speaking - but like Apple he had the right people put technologies together into a sleek/user-friendly package. Add in no legacy requirements and he was able to create one sleek looking set of vehicles. I'd buy one if it suited my needs, and never think twice about buying it.

    So far the Powerwall bit is an interesting package idea, but really it's tied up with the solar shingles. They look fairly interesting as they would allow people with covenants / HOA's preventing solar installations to use solar power. "What are you complaining about? They look like shingles, case dismissed." This isn't really as applicable to me, being in the "great white north" means solar is far less valuable than someone in sunny California or Arizona. Still from what I've read his molded solar shingles look like they work, he's just trying to make sure they last 30 years. I give him kudos for that personally. Of course going slowly might also allow him to incorporate the newer materials over time as well.

    However when we're talking Hyperloop it is a vulnerable mess. I used to work with equipment designed to work in no/low pressure. I know how much power and time it takes to bring something larger down to 1/2 - 1/4 normal atmosphere, much less something designed to be near zero atmosphere. The whole thing is incredibly finicky, and the lower you go in terms of atmospheric pressure the more likely it is to fail.

    Now not all failures are catastrophic failures. Many times you'll simply get an "unable to reach requested pressure" situation. Now you're talking about dropping the speed of the entire line down dramatically until it can be fixed, and that's not including the downtime for the actual work. This happens in a lab environment, very controlled to say the least. Elon wants to (in Cali anyway) run the Hyperloop hundreds of miles above ground. Unless he develops a new material that is not only super strong (the thickness of the material is important and also it's resistance to attack), cheap (cost of manufacture), easy to install (relative), and magically doesn't warp under temperature differentials (or even doesn't warp too much) the project is dead above ground.

    Now underground could be theoretically better, but he's still got to develop not only a new material (for longevity / safety / cost purposes) than above. Less vulnerable to outside attack at least. Still as vulnerable to not being able to reach desired pressure.

    The space capsule car would need to pressurize much higher than an aircraft fuselage. There are some very unique challenges in pressurizing aircraft hulls. If you want to see some entry level issues go look at the Raptor Aircraft channel, and the pressurization videos, on YouTube. A very interesting project, and a decent look at pressurized aircraft construction. Keep in mind that the current passenger aircraft use a lot of "power", not mention engineering genius, to pressurize a passenger aircraft a 8 psi. The fun part is how difficult it was to get 8 psi and still have it usable, but that last 2 psi is a real bear. When you're talking near vacuum a whole new set of engineering parameters come into play.

    My current theory is that Musk's vision of the Hyperloop (this isn't the first time someone has proposed this idea) will not reach advertised speeds over the distances he was originally suggesting. In fact I'll wager he'll be lucky to reach 1/2 those speeds, which isn't terrible, but cost might eat up any theoretical benefit. At that point California would almost be better building a new high-speed maglev or similar superfast regular train.
     
  5. griffinhart

    griffinhart [H]ard|Gawd

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    No. That's one of the things I find funny about this. A while back Elon Musk was complaining about how long it took him to get to SpaceX from the airport. A couple months later, he gets permission to dig a "test tunnel" for his underground city tunnel concept. Now, because he's Elon Musk, he's got a shorter commute and is hailed a visionary.

    And again... This is NOT the Hyperloop. This was never meant to be a part of the hyperloop concept. People are confusing projects.
     
  6. PaulP

    PaulP Gawd

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    Technically, there is no defined "supersonic" speed in an absolute vacuum because there can be no sound. While you may think I'm merely being pedantic, I'm not. Supersonic velocities are relative, depending on air pressure; as the air pressure goes down, the velocity goes up. That's the whole reason for the Mach scale.
     
  7. Merc1138

    Merc1138 2[H]4U

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    The more important part of my sentence that you seem to have glossed over while being pedantic about the use of the word "supersonic" is the vacuum portion. Without that, it's just a train in a tube.
     
  8. Sycraft

    Sycraft [H]ardness Supreme

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    The point is this in no way is a step towards the Hyperloop. This is technology that is commercially available, in use already, around for decades. People are acting like this is some kind of step forward. It isn't. This is shit that has been done for a long time. This doesn't go anywhere towards solving the problem of maintaining a vacuum in a large chamber safely and economically. This is like if I were to say "I'm going to make a high resolution fully 3D display!" and then I produce a prototype that's a 4k monitor. You'd rightly object that it is just a 4k monitor, something widely available, and I haven't done anything towards solving the issue of making it 3D.
     
  9. serpretetsky

    serpretetsky [H]ard|Gawd

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    I'm all for this discussion on vacuums, supersonic transport, and hyperloop projects, but I just want to make sure we're all on the same page here.
    To reiterate griffinhart, this news post has NOTHING to do with the proposed hyperloop project and NOTHING to do with vacuums.

    https://www.cnbc.com/2018/10/22/elon-musk-says-first-tunnel-is-almost-done-opens-dec-10-tweet.html
    https://www.marketwatch.com/story/e...ll-be-open-to-the-public-on-dec-10-2018-10-22
     
  10. kju1

    kju1 2[H]4U

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    Funny but I thought a tunnel was kinda a prerequisite. Im still firmly in the so what camp. I dont see why your are crapping all over it. Its like me saying Im going to build an electric airplane and when I say I have the air frame done you go "Big deal, thats been done a thousand times before."
     
  11. SLee

    SLee Gawd

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    That's a great analogy. Nobody's going to care about an "electric airplane" if the first thing they show is a used 737 airframe.
     
  12. Sycraft

    Sycraft [H]ardness Supreme

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    I'm not really sure how I can make it any clearer: They are not doing anything new, anything special, any kind of research. They are just putting a high speed train in a tunnel which has been done time, and time, and time again. This in no way goes to solving the problem of a vacuum in said tunnel.

    Your electric plane is actually a good example. If you said "I'm going to build a fully electric plane that can go 560 mph with a 9,000 mile range!" I'd say "No you aren't, not unless you get some seriously better battery technology. Batteries right now do not have near the capacity you need." If you then showed my your air frame, I'd point out that you are no closer and indeed haven't done anything: An air frame that is capable of flying is something you can get the design of for free. That isn't the problem, the problem is the batteries and until you've showed me you can solve that problem, the rest of it doesn't matter. Solving all the little problems first and saying "oh we'll deal with the batteries later" isn't a sign you know what you are doing, it is a sign you have no idea how to deal with the big problem and so are messing around.

    Same shit here. The problem with the Hyperloop was never any of the shit he's done. Digging a tunnel is something we do all the time, in fact the boring equipment they use is stuff they bought from other companies (they are currently "developing" their own machine). Building a high speed rail system is something we do all the time, not popular in the US but they are all over the world. Putting a train in a tunnel is something we do all the time, they are called subways. Combining a tunnel with a high speed train isn't done all the time, but often enough. This is all the easy shit. What is not done, what has never been done, and what has some serious, perhaps insurmountable, challenges is creating a vacuum chamber that is miles long and large enough to hold a train. Not only do you have to do that, but you have to do it safely (sudden pressurization would be catastrophic) and be able to maintain said vacuum economically (having thousands of vacuum pumps running full blast all the time would eat up energy and thus your proposed cost savings). Until they can show at least a theoretical solution to that, all the rest of this is just marketing fluff.
     
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  13. Geef

    Geef Limp Gawd

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    Its really too bad they can't do one in a straight line that's only for cargo transport. With speeds that would not be safe for people but would be fine for cargo.
     
  14. Travolta

    Travolta Gawd

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    What a great city to build an underground transport system in, considering all the potential for major earthquakes. Although Elon could then rescue everyone with his submarine.
     
  15. Sycraft

    Sycraft [H]ardness Supreme

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    Cargo is too heavy to go fast. On cargo-only lines like the heavy rail in the US, usually 70-80mph is all you go, and often slower than that. Same deal with dual-use stuff. Like the Swiss Gotthard tunnel operates at 120mph or so for passenger trains, but only about 60mph for freight. When they get really laden with cargo you can't make them accelerate fast even if you wanted to and you don't want your top speed to be too high for safety. However though not fast, it is super efficient. Shipping cargo by rail takes something like 1% or less of the energy as shipping it by truck.
     
  16. prb123

    prb123 n00b

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    As commented on many times this is not a Hyperloop. It is a tunnel with a possibility more modern Subway car in it.

    However this is still exciting. The Boring company may do for underground tunnels what SpaceX did for Orbital Access, radically reduce the cost.

    https://www.theverge.com/2018/6/14/17464612/boring-company-chicago-elon-musk-cost-estimate

    Even if all we do get is some high-speed underground railroad, that is a huge win. To get real vacuum based supersonic Hyperloops built this is a requirement first.
     
  17. PaulP

    PaulP Gawd

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    That's because I thought others had already covered this part pretty well: this system is just a test of the tunnel boring, not a real hyper-loop (too short for that). And even in the proposed systems they are not talking about pulling a hard vacuum - that would be too difficult to maintain. It will only be a partial vacuum, probably 5 to 10% sea-level atmospheric normal.
     
  18. Merc1138

    Merc1138 2[H]4U

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    You mean like way back in the first half dozen replies of this thread?

    Yeah, I did point that out except not with a positive spin. It's a train in a tunnel, there is nothing innovative about that. Running a train through a tunnel is not a test of tunnel boring either. Boring tunnels is a test of tunnel boring. Boring tunnels and then running a train through them without doing anything else regarding the vacuum has nothing to do with what was being proposed regarding hyperloop.

    If you're going to be pedantic and then point out that you missing something so obvious was because it was already covered... maybe check who said what when it was "already covered".

    There's nothing "hyperloop" about this, it's a train with a short route in a tunnel. Whoopdeedoo.
     
  19. serpretetsky

    serpretetsky [H]ard|Gawd

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    You meet a mechanical engineer that claims they're going to build a race car that will beat F1 lap times. Crazy! You swing by their house and see that they are building a vehicle in their garage. It's an offroad 4x4 pickup truck. Before the engineer says anything you say something like:
    "Thats a far cry from a race car!"
    with a serious face.

    The engineer says "This was never meant to be a race car", not really sure if they should even continue this discussion or if this is some joke,
    You reply with "I pointed that out but without the positive spin."

    Do you think the engineer is going to think you made a clever observation that can lead to some fruitful discussion? Or perhaps at this point there is not much left to discuss and maybe the engineer should go get you a beer because perhaps you are a better conversationalist when you are buzzed (risky move! maybe it's better to just try to get rid of you !)
     
  20. filip

    filip [H]ard|Gawd

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    I mean he has a point, they promised 760 mph tunnels. Now they say here it is at 155mph and we will be working to get it to around 300mph over time (this is in the article that was linked). In the US there are already rails for trains that can go up to 150mph laid in between major cities ex:Amtrak's Acela Express goes 150 mph. At 155mph you are just paying more to dig a hole to lay tacks in instead of just laying tracks.

    Meanwhile in other countries they have trains already going up to 265mph that are in service, and here we are working up to 300mph from 155mph.

    The Boring company can show me proof of concept when they have at least what other countries have speed wise.
     
  21. Merc1138

    Merc1138 2[H]4U

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    *sigh*

    Making trains run at speeds that other companies have been doing for decades is not an accomplishment. Putting trains in a tunnel is not an accomplishment. Neither one of these steps is any closer to the goal of 500+ mph train in a vacuum tunnel than any other company has done.

    Tesla claiming they can mass produce an EV that people are willing to buy, and then producing that roadster(the one that was based off of a Lotus) didn't mean squat. Actually getting their own vehicles into mass production(which they have done), getting a charging network running(which they have done), getting a network of service centers running(which they have done) are meaningful milestones on the goal to <$35k EVs. No one ever doubted The Boring Co's ability to dig a damn tunnel, put some rails in it, and basically make an electric powered vehicle to run back and forth on those rails. The actual milestones would be establishing a rail network, showing that they can get pressure to under 1 atmosphere and maintain it, demonstrate a track record of safety, actually overcome the issues people have cited regarding thermal expansion and being able to power their vacuum tunnel, etc.

    I'm not criticizing Musk for basically co-opting an idea from a century ago. I'm pointing out that he hasn't gotten the slightest bit closer to the stated goal that anyone else, and that this test track(which is basically what it is), doesn't get them any closer to running a "hyperloop" instead of just being Musk's personal subway shortcut.
     
  22. serpretetsky

    serpretetsky [H]ard|Gawd

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    Which articles are you referring to? This is Loop (not HyperLoop). Boring doesn't claim anything about speeds above 155mph on their website:
    maybe I missed something?

    Loop does not have a goal of 500+mph trains or vacuums.

    Here is information about the tunnel that is supposedly opening on Dec 10
    https://www.boringcompany.com/testtunnel
     
  23. rudy

    rudy [H]ardForum Junkie

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    On top of that cargo doesn't usually need to go fast, speed takes energy and if you are transporting cargo you don't want to increase the price by increasing the energy consumption. Regardless of any physics arguments you have a value issue. If a hyperloop was fast sure they might put overnight packages on it or special use cargo but not your usual packages.
     
  24. filip

    filip [H]ard|Gawd

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    Yeah, you know the article linked in the OP. That I guess no one read as usual. I'll admit this one is a little harder to click on than average, the hyper link to the article is the word hopes in the OP, there you will find what I found.
    Like I said very underwhelming.
     
  25. Merc1138

    Merc1138 2[H]4U

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    You don't understand why anyone is mentioning the hyperloop, that this obviously isn't? Try reading the thread title?
     
  26. serpretetsky

    serpretetsky [H]ard|Gawd

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    Yeah I see it now, thanks. I skimmed the articles before but was having trouble finding that part.
    I thought it was agreed that the thread title got it wrong and this isn't hyperloop.
    https://www.cnbc.com/2018/10/22/elon-musk-says-first-tunnel-is-almost-done-opens-dec-10-tweet.html
    https://www.marketwatch.com/story/e...ll-be-open-to-the-public-on-dec-10-2018-10-22
    Say nothing about hyperloop. Boring's website says nothing about this being part of a hyperloop test. The videos posted for the system look nothing like the hyperloop project videos I've seen before.