drgondog
Major
Dragondog the streamlining of locomotives was not for top speed but to improve mid range acceleration and reduce fuel consuption at high cruising speeds.
IIRC the discussion was about top speeds Cocky - which naturally leads to drag - hence my comments but you don't seem to be interested in much except a flame war.
That is a simple matter of physics which needs very little explanation.
The physics of 'Drag' are neither simple nor straight forward. Those that believe it requires 'very little explanation' are often at a loss when asked to produce the assumptions, the math and the solutions. Not sure which category you fit in.
However look at the horizontal connecting rod on a steam locomotive. At very low speed this is balanced since acceleating upwards is approximately the same as its weight downwards. At high speed it is scribing an irregular arc. With respect to gravity it is scribing a half elipse and accending/descending rapidly. Once the rate of decent exceeds gravity then the pistons must provide contsant acceleration though the whole cycle BUT OF COURSE YOU KNEW THAT, in the same way you knew that at 400mph a pitot tube was in a wierd unnacountable area where 400mph can read as 600.
If you have read any of my past threads commenting on Encounter reports describing '600 mph' in the dive - you would know that the pitot tube recordings at 400mph using conventional technology of 1940 introduced significant error when the fluid was no longer inviscid or incompressible.
In fact, the errors introduced include a variety of factors which required increasing sophistication to address. 1.) correction for adiabatic compressible flow, 2.) correction for position error of the static reference source to align freestream static pressure to the static port, 3.) correction for density altitude.
commonly known as the dragondog/flyboy bollox effect to win a facile argument.
Are you from France? Strike this comment, I know a lot of good people from France..
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