Can somebdy explain how a hydrolic launch works?

I know how the other types of launches work......but this i just dont get.....does anybody know how it works or do they have a link.

First of all, it's H-Y-D-R-A-U-L-I-C.

once you have that, a search here will give you more versions of an explanation than you can shake a stick at.

--Dave Althoff, Jr.

It's in german but I think it still explains itself:

http://coastersandmore.de/Rides/Xcel/xcelani.644x218.gif

Copyright by coastersandmore.de
*** This post was edited by Dragonkhan 1/12/2003 2:53:37 PM ***
*** This post was edited by Dragonkhan 1/12/2003 2:54:57 PM ***

As I posted in another topic...

On one end of a closed chamber, there is a cesspool of hydraulic fluid, while on the other end, there is tank with liquid nitrogen. In the middle of these two substances is a piston. During the launch sequence, hydraulic fluid is flooded into the piston chamber, then the liquid nitrogen is flash-boiled, creating a massive amount of heat and pressure. The nitrogen gas forces the piston forward and sends the hydraulic fluid through a turbine. The turbine connected to a cable that is hooked below the train spins very fast and causes the train to accelerate to its maximum speed.

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What is most anticipated event of 2003? the debut of Dragster, the release of Metallica's new album, the release of Terminator 3, or the release of Matrix:Reloaded...tough call.

Ummm...not quite. It's simpler than that.

The accumulator has nitrogen gas in one end under a piston. Hydraulic fluid is pumped in, compressing the nitrogen. Nitrogen is used because, unlike oxygen or atmosphere, it isn't prone to explosion under pressure. Fluid is pumped into the accumulator, forcing the nitrogen to compress. It's unlikely that the pump forces enough pressure into the cylinder to condense the nitrogen into liquid; it's easy enough to just compress it significantly.

To release the pressure, the large hydraulic valve is opened, dumping fluid, which rushes out at the full pressure of the accumulator. The idea is that the accumulator can release a lot more fluid at a higher pressure than the pump can supply by itself. Apart from the details of how the accumulator works, CP bound has a reasonable description.

--Dave Althoff, Jr.

Besides, how can you boil liquid nitrogen, let alone use it in an engine's piston cylinder? Isn't liquid Nitrogen like the coldest liquid around?

I don't know anything about this system, but I do know a bit about combustion engines and it is the heat and explosion in the top of the cylinder that creates the energy and momentum for the rest of the engine. I'm sure this system is probably completely different, but I would think if Liquid Nitrogen is used at all it would be to super-cool the components after the firing.

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cyberdman
*** This post was edited by cyberdman 1/13/2003 1:41:56 PM ***

Liquid Hydrogen is the coldest, but regular nitrogen is used in the hydrolic chamber.

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Love,
The Mole

Actually, cyberdman if you remember from your Science classes, to boil a liquid is merely to change its state from a liquid to a gas. Nitrogen is a gas at normal pressure and room temperature because it has a boiling point of (user does a quick Web search) about -321 degrees Farenheit. But that's at normal pressure, around 30" or about 15 PSI. A quick web search suggests that if you compress Nitrogen to 6,000 PSI, its point of condensation (its dew point; the temperature at which the gas will condense into a liquid) is about -65 degrees (doesn't say whether that's Farenheit or Celsius...but either way, it doesn't get that cold at Cedar Point...EVER). Besides, as you compress Nitrogen, it tends to heat pretty significantly.

So it is unlikely that there would be any liquid Nitrogen or any Nitrogen phase-change in the launch system. It just isn't necessary. Dry Nitrogen gas can be compressed enough to do plenty of work.

--Dave Althoff, Jr.

If the system uses nitrogen gas, which I imagine it will, CP has basically two choices. They can purchase a piece of machinery to extract nitrogen from the air called a nitrogen generator, or they can purchase it in bulk from a company that has their own large generator. If they elect to purchase it in bulk, it will be delivered in its liquid state and CP will have to buy a large insulated tank to store it. It is purchased in liquid form to save space during transit and storage. As far as "boiling" liquid nitrogen goes, all you have to do is pour LN into a container at room temperature and it will "boil" without the addition of heat. Room temperature is far above the boiling point of nitrogen. Once the nitrogen is at room temperature, it is in its gaseous state and can be used in the cylinders and turbines just as air would be.

ED. - Good explanation, Dave. Pardon any repetition in my post as I started typing mine just before you posted and didn't see yours until afterwards. You made a good point that the LN would not be used directly in the launch process.
*** This post was edited by jdubya 1/13/2003 11:31:02 AM ***

Boy, you guys are filled with all sorts of facts. The only thing I was assuming was that Nitrogen - in its liquid form - would not be used in this launch mechanism for the firing of the launch. You are correct though when I was thinking boil - for some reason - I was thinking water. Everytime I have used LN myself, all you had to do was remove the cap and basically you would get some Nitrogen Gas that would escape. Thanks.

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cyberdman
*** This post was edited by cyberdman 1/13/2003 1:43:14 PM ***

cyberdman, better for us to be filled with facts than to be filled with...er...something else, right! :)

In doing the little bit of research I did this morning, I learned something interesting...

First of all, jdubya, nitrogen is used as a pre-charge in an accumulator. It is not released when the accumulator is discharged, so most likely the accumulators will be precharged when they arrive on the peninsula. Very much like a shock absorber (many of those are Nitrogen charged, you know...).

Second, and this is the part I was not aware of, one of the tricks sometimes used in large-volume applications is to use a cylinder with a separate gas bottle. So again, the cylinder is precharged with N^2, but connected to a gas bottle through a pipe. As fluid is pumped into the accumulator, the gas is forced out of the cylinder, through the pipe, and into the gas bottle. Same general idea, except that now the entire volume (except the piston) of the accumulator can be filled with hydraulic fluid because no space needs to be reserved for the compressed gas. Basically it allows for a shorter total cylinder length because the accumulator and gas bottle can be stacked on top of one another.

Interesting stuff...!

--Dave Althoff, Jr.
*** This post was edited by RideMan 1/13/2003 3:20:19 PM ***

This has been discused before:

http://www.guidetothepoint.com/cpplace.aspx?mode=thread&TopicID=9732

Montu has a pretty good explanation here too: http://www.geocities.com/themontu/Launch.html

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cyberdman