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The water would no longer be pushed sideways into the pipe wall (lower C value in the equation), but the angled pipeline would require a longer length of pipe to reach the equator(bigger L value). 

The energy savings of not fighting the Coriolis Force would be cancelled out by having to pipe the water farther.

The formula John Creighton gave for the local acceleration is correct.  Just be sure to compensate for latitude when you do the calculation. 

(That equation is:  a = g - w r sin(latitude) )

Angular momentum, per se, does not figure into the equation, but inertial accelerations do.  Centripetal/Centrifugal acceleration is what causes the variation in local acceleration, and consequently the head difference that pumps the water.  Coriolis force is a cause of additional drag and energy loss.

With the difference in sea level, there should be a difference in gravitational acceleration, but it will increase toward the equator, and reduces the head difference that's moving the water (making the flow even slower). 

Regarding the idea of using this to propel water to space:

You'll notice the interchangeable use of "energy" and "head" when describing the fluid energy equation.  By dividing each term in the equation by the specific weight of water, you can convert every term to a distance value, or head (pressure head, elevation head, velocity head, pump head, etc.).  This is the height of the column of water corresponding to that much potential energy (or alternately, the depth at which the pressure would correspond).  It's also the height to which the water would rise at that point if you just opened a nozzle and let it fly.  It will never go higher than that under its own power. 

The elevation difference is only a few kilometers, and it won't spurt very high moving at one millimeter per second. 

This effect will never allow you to pump anything to orbital heights, because the head doesn't correspond to an orbital height.  Any "pipeline to space" idea will need to use something else.

Don't you mean "runcible spoon", Trebuchet?   :laugh:

I had a professor once who insisted that if there was a fluid head difference (potential energy gradient) between two ends of a uniform level pipeline, no matter what the continent-spanning length of it might be, a fluid could be induced to flow from one end all the way to the other.  He said that all head losses (losses of flow energy) were velocity dependent, so at some point the flow velocity would fall below the point where friction, viscosity and other velocity-dependent losses were strong enough to prevent the flow.  Similar flows were already observable in ocean bottom currents which - though it might take thousands of years - trickled from the pole to the equator propelled by nothing more than a slight head difference.

In short, Errorist, his claim was that your claim was theoretically possible, provided you don't care how fast the flow is moving. 

Unfortunately, the expected flow velocity is hardly fast enough to keep the water at a stable temperature all the way from the poles.  It would heat up to within a few degrees of equatorial temperatures along the way if you ran your line along the surface.  You'd need pumps just to get the water to the equator in your lifetime, much less while it still had a chill on it.

It will pump water, but you can forget this as a heat exchange mechanism.

The applicable equation is Bernoulli's Equation adjusted for external work and potential losses, also called the Fluid Energy Equation.  It goes like this:

P1 + rho1 * a1 * h1 + alpha * rho1 * v1 ^ 2 + W =
= P2 + rho2 * a2 * h2 + alpha * rho2 * v2 ^ 2 + Q

where

P1 & P2 are the pressures on each end of the pipeline,
rho1 & rho2 are the fluid densities on each end,
a1 & a2 are the local accelerations (gravity + centripetal force) on each end,
h1 & h2 are the elevations on each end,
v1 & v2 are the flow velocities on each end,
W is the total pumping work added to the fluid over the entire pipe,
Q is the total loss in potential energy over the entire pipe,
and
alpha is a constant correction factor for non-uniform flow across the pipe's cross section.

The basic idea is that the energy on one end of the pipe is the same as the energy on the other end of the pipe.  This equation can be found in any Fluid Mechanics textbook, as well as equations for computing W and Q.

If you plug appropriate values into this equation, assuming W = 0 and Q = C L v^2 (where L is the pipe length and C is some system-dependent constant describing the energy losses per unit length), you see that v has to be very small before any of the other terms become larger than Q, because L is so freaking huge.  And nothing will move until the other terms sum to more than Q.  Without a lot of big pumps, you're probably looking at a flow velocity of a few millimeters per second.  It might outrace a snail - maybe, with a really big pipe.

This will sound odd, but have you tried swinging the lengths of tubing around overhead like a sling?  This will give you a relatively simple means of controlling the flow rate through and around each tube. 

I don't recall the name of the children's toy, but I do recall that it operated in roughly that fashion and had a fairly wide range of pitch.

PS: Before I ran across this post, I had completely forgotten about this simple, tunable sound transducer.  I was looking for something like this recently.  Thanks.

I hope O'Keefe gets the chancelorship at LSU.

I don't know if Zubrin would be a good or bad choice for NASA administrator.  On the one hand, most of the better NASA administrators have had an agenda, a mandate from their supporters, or both (Faster-Better-Cheaper, straighten the books, put a man on the moon, etc.).  NASA needs focus, and needs it badly.  Zubrin could supply that.

On the other hand, he's Robert Zubrin!   :laugh: 

I'm uncertain if a loudmouthed spitfire can develop the effective cat-herding strategies necessary to make it in the upper echelons of NASA.  One might do better to look for another candidate, one with the requisite focus but without a history of blanket criticisms, minor insults to former employers, etc.  Zubrin's got skill and enthusiasm, and he's a true leader.  I admire the man greatly.  I'm also happy to see him with his own company, because he'd probably have suffered greatly from submission to the bureaucratic politics of NASA. 

NASA needs someone at home in the environment it offers.  Zubrin isn't that guy.

Give the administrator's job to the current director of the Kennedy Space Center.  Between the hurricanes and the fires, I'm sure they need a vacation right about now. :;):

Sure, let 'em ship food.  It's good practice for sending the pharmaceuticals and other manufactured goods later.

Drat!   :bars: 

Don't tell me one of the one of the world's greatest living adventurers had a point!   :bars2:  I don't want to hear it!

Whatever happened to ignoring the ramblings of old men!  Where is progress for Progress's sake!  Hasn't the world's largest expanse of unspoiled land been beyond our grasp long enough!  Who cannot see the virtue of showing man's innate power over nature!

I want McMurdo Station to be another Cairns!   :realllymad:

*cough!* *wheeze!* Where's my inhaler!  *snort!*

I mean, um...  Hmmm...  Perhaps the environmentalists are merely waiting expectantly?

And when that happens, I'm sure that I will lose all reservations about international cooperation on individual space missions...   

Of course, there is hope as pointed out by Spacenut:

It's important to note that this event is statewide only.  It's not national, or international.  However, given the apparent gradually decreasing efficiency of progressively large organizations, perhaps a national or international organization would be less desirable.

I'm of mixed feelings on this. 

When I reach 85 years old, I expect to be left alone to say whatever I want. 

On the other hand, Edmund Hillary ought to shut the heck up and let them build the road. 

If they built a road to the summit of Mount Everest, I'd hate to see the litter people would leave along the way.  Of course, with regular cleanups, Mount Everest might be prettier than it is now.  (No more candy wrappers, spent oxygen bottles, dead bodies, etc. left lying around.)

It's not the little companies' fault that patents expire.   :;):

Big corporations hold many of the relevant patents, it's true.  Small companies have to pay to use them commercially, which drives up prices.  Further, many small companies are forced to seek funding from sources by conceding portions of proceeds from their own patent development.  However, it's gradually becoming clear that the technology represented by many of those patents is not adequate to the task, so it doesn't ultimately matter who owns them. 

The current "small low-cost launchers" are nothing of the kind.  They were quite innovative a few decades ago, but I would not recommend the average modern rocket to a start-up company wanting to specialize in launch vehicles. 

If you want to start a new company, get a new product.

I agree we're reaching the limits of conventional rocketry, but I don't agree with this assertion.

I can't concur that the "big guys" will necessarily steal ideas from the "small guys".  Such a theft would have to occur in the courts as well as the markets.  Are there no trade secrets?  Are there no patent laws?

Nope, rapid development will not be forthcoming from the small business people.  Profit margins do affect the rate at which money and man-hours can be poured into a project, and small businesses barely have any in comparison. 

But that does not mean that no development will be forthcoming.

Although small companies do tend to be more efficient than larger companies, the difference isn't vast enough to give them the edge all by itself.  However, given a uniquely innovative, sufficiently legally protected, and truly superior functional solution, a small business could become a big business over time.  The big guys were small guys once, too. 

If you had a small AltSpace startup, trying to compete directly with an aerospace collosus fifty times your size would be foolhardy.  There has to be a barrier between you, some mouse hole to hide in while you grow bigger...  Fortunately, such holes exist, in the form of patent monopolies and other legal protections.  You can find your company's niche.  All you need to get into it is some really good legal advice and the next big idea.

Climbing out again once you're there, that's the subject of a whole other post.   :;):

The main difference between motors using the Otto cycle, Diesel cycle, and the various turbine types is operating torque, which affects everything else about the motor design.

The efficiency of any heat engine cycle varies according to what pressure you run it at, and pressure determines the minimum torque needed to run a rotary motor using that cycle.  Since each cycle works most efficiently at a different range of pressure, each engine type works best in a different range of torques. 

For example, a diesel motor needs huge pressures and consequently huge torques, but an Otto motor can work at lower pressure and a turbine motor can operate at near zero pressure.  Consequently, you will never see a model airplane using a diesel - those tiny little motors would burst apart before developing enough pressure to run a diesel cycle.  But you can run them with a turbine or otto cycle motor.  A turbine engine can't quite reach the same overpressure as an Otto cycle engine, so it's range of torques is smaller, but can run at even lower pressures.   A turbine engine could even conceivably run on the surface of Mars without extensive vacuum modifications, though you wouldn't get much work out of it.

There is a theoretical smallest optimum size for a turbine engine using pressure differentials alone to drive the engine.  Below that, a simple fan turbine can't reach a very high efficiency.  However, fluid adhesion can drive a turbine as well, allowing turbines to reach sizes smaller than the smiley at the end of this sentence.