Plane designers figured out long ago that for the best aerodynamics you don't actually want a pointy nose - a big hemisphere like the bottom of a raindrop performs best.
So why does this have a pointier nose? Just for PR?
So why does this have a pointier nose? Just for PR?
You act as if you have expertise in aerodynamics, but don't share the sort of details an expert would. An expert would say something along the lines of, "Cool fact: big hemispheres are more aerodynamic, but the TGV chose a pointy nose because of X, Y, Z." Or even, "Big hemispheres are more aerodynamic, but also involve engineering tradeoffs X, Y, and Z. I wonder if that's why they went with a pointy nose?"
That kind of comment would be awesome! Informative and interesting. Instead, your comment across both arrogant and ignorant. Arrogant in that you assume that any deviation from your understanding is wrong, and ignorant because your proposed rationale is extremely unlikely, and flamebait besides.
Might be better to honestly ask why rather than starting by trying to insinuate that the people who designed this are idiots or did it only for PR.
Wave drag of 1/2*rho*v**3 is about 4 megawatts for air. Long sides will reattach flow somewhat even with a bad shape.
With steel on steel so 0.001 to 0.002 m * C_rr * v^2 is about 2.5 to 5 MW. At a full load maybe even 6 or 7MW.
I have nfi how to do skin drag, but it's probably around the same order.
Thus we conclude that once Cd is below 0.5ish other concerns start to become a lot more pressing.
Namely tunnel shockwaves, passing suction, driver space and comfort, crash ratings, down force for the engine car, and so on.
Even if it looks cool so 10% more people use it, that's a net efficiency win.
I can imagine that 100 year old bridges have a habit of dropping bricks on trains that send massive pressure waves every 10 minutes all day long...
However the manufacturer might be expecting a significant business through the alps, given the base tunnels Switzerland has been digging.
That would make high-speed tunnel entry a larger concern than it’s historically been for the french market (most of the tall mountains are on the edges of france so high speed lines don’t have a surfeit of tunnels, probably unlike japan which is rather mountainous).
What exactly improves PR for a train having a pointy nose vs a rounded nose?
There also is a difference in velocity and in expected air pressure, airplanes don’t have to bother about not creating pressure waves for planes passing them at a few meters distance while flying in the reverse direction and airplanes are relatively much longer than air planes compared to their width. That means that a much larger fraction of the air resistance comes from the sides of the train.
A round nose has a flat bit at the front which reflects radar direct back towards the enemy that you're flying towards. Military planes generally have no surfaces facing directly forwards for that reason - even surfaces made of plastics reflect some radar when they get wet.
Passenger airliners travel at slower speeds for which more round noses are actually better (eg to prevent flow detachment).
In fact, iirc I read somewhere that Airbus’s more blunt noses are the result of newer CFD-based design techniques whereas Boeing reuses their pointy nose from previous designs.