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Modern trains are very much designed for aerodynamics, look at something like http://www.hitachirail-eu.com/super-express-iep_57.html


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It's not flight, but a Chinese designer, Chen Jianjun, came up with this for trains:

https://www.youtube.com/watch?v=Oh5W_-_WFvc


I imagine aerodynamics isn't very important when you are shunting the train about on the switch yard...

Trains are relatively long in proportion to their width. That makes the sides of the trains become relatively more important for aerodynamics than the fronts.

Possibly, making the front more aerodynamic has so many disadvantages that it’s not worth it. For example, a train with a long nose means less space for passengers in a given length of train. It also may be a bad choice aerodynamically if you want to have the ability to combine multiple railroad cars into a single train.


Wouldn't this destroy a bullet train's aerodynamics?

So which designs have gotten close to a significant increase over normal atmospheric bullet trains? That's addressed in my comment


Hey, a train has airspeed. :)

If this is a high speed train, and the front car of the train is always being rotated backward, how do you deal with making sure that this first car is aerodynamic, and remains aerodynamic once it is no longer the first car?

Traditional trains have wheels and engines, which are quite heavy. And with a traditional train you're trying to minimize losses due to air resistance, which is not an issue in a low pressure tunnel.

That makes a lot of sense, since almost all of the resistance the train faces is air resistance.

You can plasma sheaf the train head. The stability of wheels/rails and other mechanical stuff at say 700km/hour is probably a bigger issue than air resistance.

A train can easily run in a head- or tailwind in the same order of magnitude as its groundspeed.

You may want to look at the Japanese train 'bodycount'. They've arguably the most elaborate rail system and I believe it's still safer than air.

The Germans were really keen on aerodynamics for surface vehicles in the 30s; trains too! Here's some video footage of the Schienenzeppelin (propeller-driven diesel train) during it's preliminary 1930 test runs:

https://www.youtube.com/watch?v=E-ID_ktSoLY

(Part two of the video: https://www.youtube.com/watch?v=ZY7PIIV0nIs )

It later set a 143mph land speed record for a petrol-powered train, although it didn't exactly catch on (in no small part due to safety concerns concerning the passenger-mincer at the back). More here:

http://en.wikipedia.org/wiki/Schienenzeppelin


On your personal advantage — most high speed train designs are pressure sealed nowadays, so there's even less than on conventional trains.

Maybe they plan a hybrid, so the same train will travel on regular and tunneled tracks.

Though I was expecting that new materials and design could reduce the air friction even more in the future.


I'm not talking about high speed trains. I'm talking about medium speed cargo trains. Despite the lack of a flush body, each container does draft the following one, greatly decreasing drag.

Each car in a normal cargo train doesn't have its own engine. They are pulled by locomotives. This is more efficient than putting an engine in every car.

Passenger trains typically do have engines in every car, but we're not talking about passenger train here.


Don't trains usually have to accommodate the potential for standing passengers and thus have to have a much smoother acceleration curve than is strictly necessary for car comfort?

No, the physics of that don't work at all. Trains for example cannot handle gradients that cars manage with ease.
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