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Highspeed vs conventional train
[Subject Prev][Subject Next][Thread Prev][Thread Next] To: "Sseaint Org" <seaint(nospamat)seaint.org>
 Subject: Highspeed vs conventional train
 From: "gregory szuladzinski" <ggg(nospamat)bigpond.net.au>
 Date: Sat, 30 Oct 2010 19:21:36 +1100
REPLY:
When you ride a HST, the feeling is similar to that being on a
plane,
but with different ups and downs.
Now, to nitpick (right spelling?) on the opinion
below.
Work is force multiplied by a distance travelled.
The multiplier of 27 is on the force. The distance covered, in
a unit of time, is 3x larger,
so the energy needed is 9x larger.
But the aero resistance is only a part of the total, so energy
input will not grow that much.
Also, the aero shaping is better, which further descreases the
multiplier.
The frequencyofuse factor will divide the result by
3.
Sincerely
Gregory from Oz
OPINION:
On Fri, Oct 29, 2010 at 11:53 AM, IRV FRUCHTMAN <ifaeng(nospamat)yahoo.com> wrote:
> Fellow Engineers, > > High speed trains are wonderful engineering feats, but I don't believe > saving energy is one of them. As I recall from my school days: drag force= is > proportional to speed squared and power (read energy) is proportional to > speed cubed. Therefore a train moving at 300 mph, compared to a train at = 100 > mph, uses (300/100)^3 =3D 27 times as much energy. If the requirement f= or > the number of trains is reduced by 1/3 =96 to move the same number of peo= ple  > then the increased energy use is 27/3 =3D 9. Therefore, 9 times as much e= nergy > is required to move the same people/ load with a high speed train as > compared to "low" speed train. > > > Given a choice, I'll take an airplane.

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