Sunset East Eligible for HSR Funding?

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Mobile - New Orleans are really too close together for real high speed service. They are only 145 miles apart.
I would think that distance is one of the few where a 220 MPH train could make trips practical that simply would not be any approximation of practical by any other mode of transportation. A 220 MPH train covering 145 miles could make the trip in about an hour each way, which is viable for a daily commute. There's no way an airplane or an automobile is likely to be remotely time competitive with that.
Point taken. The existing right of way is straight enought for most of the distance to allow speeds up to this amount. The tracks just need relocation, as I have said before: About 25 feet straight up. This will eliminate all the road crossing and trespasser issue at one swoop. Make it enough higher over Bay St. Louis and Biloxi Bay, and eliminate the drawbridges. Think of a time more on the order of 90 minutes to allow for stops and some slower running into the city centers at the ends. This should still be fast enough to capture quite a bit of traffic, particularly if there was a western extension to a point slightly further west, say like Houston and San Antonio.
 
Mobile - New Orleans are really too close together for real high speed service. They are only 145 miles apart.
I would think that distance is one of the few where a 220 MPH train could make trips practical that simply would not be any approximation of practical by any other mode of transportation. A 220 MPH train covering 145 miles could make the trip in about an hour each way, which is viable for a daily commute. There's no way an airplane or an automobile is likely to be remotely time competitive with that.
Point taken. The existing right of way is straight enought for most of the distance to allow speeds up to this amount. The tracks just need relocation, as I have said before: About 25 feet straight up. This will eliminate all the road crossing and trespasser issue at one swoop. Make it enough higher over Bay St. Louis and Biloxi Bay, and eliminate the drawbridges. Think of a time more on the order of 90 minutes to allow for stops and some slower running into the city centers at the ends. This should still be fast enough to capture quite a bit of traffic, particularly if there was a western extension to a point slightly further west, say like Houston and San Antonio.
Lafayette, LA to New Orleans via Baton Rouge is about 135 highway miles, similar to the Mobile to New Orleans distance. So Lafayette to New Orleans is another potential high speed commuter rail route.

Getting from Lafayette to Houston is more like 215 highway miles, which is harder to make work as a high speed commuter rail route at 220 MPH. On the other hand, building a HSR line from Lafayette to Houston might allow people in Lake Charles and Beaumont to commute to Lafayette and Houston.

Mobile to Montgomery is about 170 highway miles, which probably needs to be somewhat faster than 220 MPH to be a reasonable commute, unless you're just focused on allowing people in the small towns between them to commute to both.

Montgomery to Altanta is about 160 highway miles.

Atlanta to Greenville, SC is about 145 highway miles.

Greenville to Charlotte, NC is about 100 highway miles.

Charlotte to Greensboro, NC is about 90 highway miles.

Greensboro to Durham, NC is about 50 highway miles.

Durham to Richmond, VA is about 150 highway miles.

Richmond to Washington, DC is about 100 highway miles.

It's probably possible to build HSR all the way from DC to Houston if your goal is to make every mile of high speed track be both a viable route for commuting into a major city from various small towns, as well as a part of a viable long distance intercity route. In many cases, it can also be practical to live in the downtown of a major city and commute to an adjacent major city.

It may very well be the case that when some of these routes are first opened, the major city to major city time needs to be closer to 90 minutes than 60. Route 128 to Back Bay on Amtrak is about 10-11 minutes now, as is New Carrollton to DC. And neither 128 nor New Carrollton is far enough out from the city to be the point where the 220 MPH track will start, if the 220 MPH track is not built in a tunnel under the suburbs. If you're spending 15-20 minutes on each end of the route traveling along a slow right of way through the city, that's 30-40 minutes when you count both cities, and only leaves 20-30 minutes for traveling on the 220 MPH+ track if the trip is supposed to be completed in under 60 minutes; 30 minutes at 220 MPH only covers 110 miles.

On the other hand, if HSR can be built through tunnels through mountains, why not HSR through tunnels 100-200 feet under the surface through the suburbs?

And why limit speeds to 220 MPH in the long run?

With conventional speed routes, we often see studies of both what it would cost to achieve 79 MPH and what the running times would be, and also costs and running times for 59 MPH or 110 MPH. I think it would make a lot of sense for high speed commuter rail studies to look at the costs and benefits of the tunnel through the suburbs option, and at the potential benefits of 300 MPH operation once that equipment is developed (and what can be done relatively inexpensively during initial construction to save money upgrading to 300 MPH later, especially in terms of generous spacing between the two tracks).

I bet with tunnels under the suburbs and 300 MPH running, Lafayette LA to Houston TX could be under an hour.
 
And why limit speeds to 220 MPH in the long run?
Same reason as lot of other things. NO VISION. Right now 220 is about as fast as anyone considers practical. Why? Don't ask that if you want a coherent answer.
George, I think you are overstating your NO VISION case on that one. The engineers involved are not as complete twits as some of us on this board make them out to be .... Juuuuuust kidding :lol:

There exists a body of coherent discussion and literature that I have seen on the subject revolving around the exponentially increasing energy cost as speeds increase. Like all good engineers, people try to model this and arrive at some notion of an optimum speed balancing travel time against energy costs, and based on that 220mph is sort of a ballpark figure that is used these days. I have seen studies from SNCF, DB, the JR East and even one from the Chinese all coming to numbers in the same ballpark. Unfortunately none of these are on the internet AFAIK. Another issue is the cost of maintenance of infrastructure. The cost of track maintenance for example, goes up rather impressively as speeds are increased.

And BTW, the issue is not the inability to deliver the needed power to the train. That is easily done - so no need for heavy banks of batteries on the train Joel :) .

The primary issue is optimizing cost against benefit. It has more to do with economic viability than technical feasibility. However, AFAICT, if the cost issues can be figured out then everyone agrees that technically there is nothing stopping speeds of even 400mph.

Of course depending on energy efficiency and attitude towards such etc. the point that is considered optimum could change. But laws of physics are hard to change and the exponential growth in air resistance with speed remains on the books of nature even if the legislature writes all sorts of laws banning such and railfans want to wish it away :)
 
JIS: I hear what you are saying. Nonetheless, what is considered a practical maximum speed has increased a lot over the last 50 to 100 years. I do not see any convincing reason to say that we are at the end of the road, as yet.

Yes, by the time you get into the 150 mph plus range, the aerodynamic resistance, which is usually the V^2 term in the resitance formula has fairly well taken over. However, I do not think that means we are at the ceiling. For example, look at how much the aerodynamics of the Shinkansen trains have improved since the Series 0 sets. Have we reached the end of the road on these things? I don't think so. Will the energy consumption per passenger approach that of an airplane on a per-seat basis at even 400 mph. Probably not. Are there other issues that come into play above 200 mph? Probably so. Are they insurmountable? Probably not.

Can sufficient power be obtained and then delivered to the wheels to run 300 plus mph? Yes, obviously. Can it be applied to the rail without wheel spin? That may be the issue. Is there a fix for this issue? We shall see.
 
JIS: I hear what you are saying. Nonetheless, what is considered a practical maximum speed has increased a lot over the last 50 to 100 years. I do not see any convincing reason to say that we are at the end of the road, as yet.
Yes, by the time you get into the 150 mph plus range, the aerodynamic resistance, which is usually the V^2 term in the resitance formula has fairly well taken over. However, I do not think that means we are at the ceiling. For example, look at how much the aerodynamics of the Shinkansen trains have improved since the Series 0 sets. Have we reached the end of the road on these things? I don't think so. Will the energy consumption per passenger approach that of an airplane on a per-seat basis at even 400 mph. Probably not. Are there other issues that come into play above 200 mph? Probably so. Are they insurmountable? Probably not.

Can sufficient power be obtained and then delivered to the wheels to run 300 plus mph? Yes, obviously. Can it be applied to the rail without wheel spin? That may be the issue. Is there a fix for this issue? We shall see.
I am not suggesting that we are at any absolute maximums of anything. The main point I was making is that there is the issue of economic viability in addition to technical one and I would suspect that we agree on that one too. In the final analysis, if the operating cost is non-viable for the next 10 years it will probably fail if built today with such operating assumptions as to bear a non-viable economic cost, even if it becomes viable due to further development of technology after that period of time. But your point about choosing as straight an ROW as practicable is a valid one, notwithstanding that, again within the reality of how much would it cost to obtain such an ROW at present.

As for aerodynamic drag, I believe it will improve to some extent by reducing the drag coefficient CD, but O(v2) in Lord Rayleigh's equation does not change. And consequently power needed to overcome drag will most likely remain O(v3). Also one thing to keep in mind is that airplanes in cruise are actually facing less air resistance than trains at the same speed (except perhaps the train to Lhasa :) ) because the air density is much less at the plane's cruising altitude than what the train faces at ground level, i.e. the rho in Rayleigh's equation is less, though the effect of the reduction is only linear. OTOH the plane has to spend energy to get to said cruising altitude doing so at a higher angle of attack thus subjecting itself to greater air resistance than in level flight for that period.

For those that want to learn more about this and are somewhat inclined towards Physics and Mathematics, you could start in the Wikipedia article on Drag Equation.

You do bring up the interesting issue of rolling friction at the wheel/rail interface as speeds increase. To some extent that issue can be circumvented by using LIM but most likely at significantly greater cost of infrastructure construction and maintenance specially for operation at such high speeds. We afterall know that this can be done from the various Maglev experiences.

Fascinating area of discussion. I find it difficult to get my hands on analysis specific to railway usage. Do you have anything at all on line from the Japanese in this area? Have you come across any IEEE publications that I can lay my hands on? Thanks much. Being an engineer at heart I love to get deeper understanding of these issues of optimization for a specific set of circumstances.
 
Sunset East is probably not the right thread for this discussion, but I am sure that those interested will find it.

Train resistance is most simply expressed in the form of a TR = A + B V + C V^2 formula, where "V" is the speed and the A, B, and C are constants.

In general,

"A" represents starting resistance and internal machine friction, and is constant regardless of speed.

"B" represents resistance due to deflection of the track and deviations from perfect smoothness of track

"C" is primarily aerodynamic

"A" and "B" are both relative to train weight, when different lengths of trains of the same equipment are analyzed. "C" includes a front end constant plus a length factor.

For high speed trainsets operating on tracks permitting high speed operation, both the "A" and the "B" terms are relatively small, and become less and less significant as actual speed increases.

All these terms are derived primarily from measurements of actual train performance as determined by power draw in relation to speed and acceleration. Since proper derivation of these terms is quite expensive, the results are usually not published.

If doing this for freight, the terms can be extrodinarily complex, as A, B, and C depend upon the characteristics of each piece of equipment, and, for the "C" term its relationship to its neighbors in the makeup of the train.

Power and tractive effort: TE = P/V. Therefore, TE is infinite at a speed of zero. This obviously is not possible, and even if possible could not be applied to the rail. Generally, at low speeds TE is limited based on a permissible acceleration rate.

Adhesion has also been determined to decline with speed. Usually this is not a factor in EMU's, but can be with high powered light axle load locomotives.

Again, this factor is experimentially determined. One set of formulae is in the form of Adhesion = D / (V + E), where D and E are constants and V is the speed. Usually there are multiple values used here, one for dry rail which is effectively the maximum, another for wet rail, which is the maximum to be considered in scheduling, and a third for braking which is a worst condition situation that you had better consider in determining safe stopping distances. For the accelerating condition, the factor must be multiplied by the proportion of the train weigth on powered axles. For braking, the full weight may be used, or a reduced factor based on some ratio of failed brakes included.

Numbers: All these are in metric units, because that is the way I have dealt with these things. The numbers given are not the real ones, as these are regarded as confidential by the equipment supplier, but the are in the general range of those that are used.

For train resistance for high speed train sets, with "V" in km/h and resitance in kilonewtons, think of something on the order of: 8.00 + 0.08 V + 0.0008 V^2 for a train with a weigth of around 600 metric tonnes.

For power, think in terms of motors of around 275 to 325 kilowatts each times however many axles you feel like so long as your weigth per axle is in the range of 13 to 16 tonnes. To get TE, you must convert the "V" term from km/h to meters/second.

For adhesion, the Shinkansen braking adhesion formula was published in AREA Bulletin No.727, October 1990. It is

Adhesion = 13.6 / (V + 85) again, remember these are metric units.

Also this is a ratio, so at say 200 km/h, the Adhesion is 4.77%. If this sounds low, it is. The braking rate is somewhat higher than this, because braking is assisted by train resistance.

End of lesson.

All further work is left to the student.
 
Of course depending on energy efficiency and attitude towards such etc. the point that is considered optimum could change.
Right, and what happens if solar panel research discovers a way to use a completely different set of materials than are used for today's photovoltaic cells that leads to the cost per kilowatt hour twenty years from now being 1/4 or less the cost of a kilowatt hour from the grid today? What if people want to travel twice as fast for the same money instead of traveling for 10% or 20% less money (when you factor in that energy probably is only a small fraction of the ticket price)?

Or what if we get a lot better at figuring out how to put wind turbines in the places that will get optimum wind, and realize that total US wind power jobs is a more important number than US wind turbine manufacturing jobs, and get some other country with cheaper labor to build the turbines so that we can more easily afford the total cost of manufacturing, shipment, and installing the turbines (with that last step necessarily involving US labor)? I don't think we can be at all certain that a kilowatt hour of wind twenty years won't effectively cost half of what a kilowatt hour from the grid costs today.
 
. . . and get some other country with cheaper labor to build the turbines so that we can more easily afford the total cost of manufacturing, shipment, and installing the turbines
One of the last things we need to do in this country is export more jobs.
My understanding is that a kilowatt hour of wind (probably delivered at the time most convenient for the wind turbine) is currently a little more expensive than burning enough coal to get a kilowatt hour (probably at a time someone actually wants to consume it). The reason we have wind turbines at all probably has something to do with the government wanting to work towards more environmental friendly technologies.

I think a 30% reduction in the cost to get a kilowatt hour out of a wind turbine might end up being cheaper than burning coal, even without a government subsidy.

So, I'm wondering if a 30% reduction in the cost of wind power might lead to a factor of 10 increase in the number of wind turbines that are installed in the US.

And I suspect that if you have to choose between 10 imported wind turbines installed in the US, or one domestically manufactured wind turbine installed in the US, that the lost installation jobs from those 9 wind turbines that don't get installed are not going to be made up for by the manufacturing jobs to manufacture that one wind turbine in the US.

Of course, I don't know if these are the real numbers, but I do think that there is some point where a change in 10% of the cost of a wind turbine installation will probably lead to a factor of 10 difference in the number that are installed. Which may lead to a higher volume of orders driving down prices further so that maybe you can even afford to ``waste'' some of the energy produced by wind turbines when people aren't ready to consume it so that you can justify installing even more wind turbines which might create even more installation jobs.
 
The primary issue is optimizing cost against benefit. It has more to do with economic viability than technical feasibility. However, AFAICT, if the cost issues can be figured out then everyone agrees that technically there is nothing stopping speeds of even 400mph.
One of the features we find on the NEC is that a passenger can choose how much electricity they want to pay for and how fast they want to go by choosing to buy a ticket on either the Acela Express or the Northeast Regional.

I'm wondering if the California HSR folks could decide that 95% or more of the trains on the timetable are indeed going to have a maximum speed of 220 MPH or 250 MPH for the first several years of revenue service for the sort of passenger who would prefer the Northeast Regional, but that a few premium trains will reach a top speed of 300 or 400 or 500 MPH for the folks who would choose the Acela Express.

Perhaps the fastest trains could initially run at off-peak times if that will allow several slots to be allocated to the trains running at the non-standard, faster speed. Or perhaps if the trains stopping at stations always pull off the double track mainline, that might provide adequate opportunities for 300+ MPH trains to pass the slow 220 MPH trains. And if the fast trains prove popular enough, maybe some 50 mile long third tracks could be added if that's what it takes to get mixed train speeds at peak travel times.
 
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