Re: Fork installation - How stupid is this hack?

On Aug 25, 6:22 pm, jobst.bra...@xxxxxxxxxxxxxxxxxx wrote:
someone wrote:
Another one is that when a train passes rapidly past a station
platform, it sucks waiting passengers into the moving train.  Air
at these speeds is an incompressible fluid and a stiff bow wave
blows laterally from the front of the train.  This air returns more
slowly and someone who braced against the bow wave generally over
reacts and falls forward afterward and believes the train
sucked.  Of course no one can show where this vacuum cleaner dumps
all the air it sucks in.
When I am driving on a two-lane highway and pass a truck going the
other direction, the steering wheel twitches toward the truck. Is
there a mechanism by which the car 'braced' against the bow wave and
is 'overreacting?'

I think you'll have to define your terms more accurately and how your
car diverges from its prior course.  All my cars have always been
blown away from a large truck or bus approaching at high speed.  If
yours doesn't do that it is unique from my experience and certainly
counter intuitive.

When traveling with HSR in Europe there is conspicuously no suck
pulling trains into each other.
When traveling Amtrak in the USA, there is a conspicuous movement of
the cabin toward a train passing the other direction.  Since
European high speed rail has had engineers put more care into its
aerodynamic design, and is not running on repurposed low-speed
freight lines, perhaps the experience is less relevant.

Are you sure about that?  It is precisely the scenario that high speed
trains have so much suck that they, at times, make contact on standard
double track railways.  I know that story is fantasy or it would have
appeared in the press and especially railway trade magazines.  No such
reports exist as far as I and fellow railroaders have experienced.

I just got through riding on the Eurostar (Chunnel) and Paris -
Marseilles TGV line as well as German ICE from Nürnberg to München, all
on standard spaced double track, and merely noticed window "rattle"
when passing opposing high speed trains, even in tunnels.

Your report doesn't ring true to my sensitivities.

Jobst Brandt

The effects I described are most striking when there is a slight
crosswind and you are on the lee side of the passing large vehicle.
The pull toward the passing vehicle is *much* stronger than one would
expect from mere blocking of the crosswind, as you can easily find by
comparing passing trains to passing tunnels or barriers. That ought to
provide a hint.

-pm
.

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