Draft Cone around Corners

Does the draft cone wrap around corners, or does it point directly behind the rider in the direction they are currently facing? In other words, if we take a sharp corner do we experience less draft through the corner? A practical version of this question is: is an attack in Les Intestines in RGV more likely to get a gap at the same wattage than along a straight road?

Also, I recall some corners used to be speed limited (the hairpin in Crit City for example). Is that still the case? I feel like I heard that was removed, but can’t remember and am not finding recent articles/posts on it.

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Drafting works by the lead rider creating turbulence in the air, so IRL the draft zone would be whatever space that rider’s body has passed through. If they’ve just finished a right hand sharp turn, the air now immediately behind them will have been disturbed, but the draft zone won’t extend in a straight line out behind them at every moment because they didn’t ride through that straight line. The draft zone would be a curve.

Think about it this way: you’re riding along a straight road, and a cyclist turns very sharply onto the road in front of you. You won’t suddenly feel a draft benefit just because you’re behind them–not until you reach the air they actually rode through.

It’s going to be a minimal impact though–there’s a draft effect out to 10m or more for a single cyclist, but it’s a very small benefit at that point. For a significant benefit, you’re talking 2, 3, 4m tops. And most cyclists don’t make turns that sharply. So if a cyclist turned onto the road sharply between 2-4m ahead of you, you’ll be in their draft almost immediately anyway. And anyone following their exact line would be in their draft the whole time too.

That’s IRL, AFAIK. I don’t know how Zwift has modeled the draft zone through turns.

Yes, sorry, I was specifically interested in how Zwift implements it. In real life sharp corners are attack points because you have to brake into them and also have to choose how much bike lean you are comfortable pedaling at and when to start/stop coasting to avoid pedal strike and thus have an opportunity to create a gap by pedaling hard out of them if someone over brakes or gets the corner wrong in some way.

But in Zwift, you can rail every turn at full speed and full gas so corners shouldn’t make good attack points. But it sometimes feels to me like in the Les Intestines segment in RGV it’s harder to stay in the blob than anywhere else and quicker to get spat out the back, which had me wondering if Zwift is doing some weird draft cone thing where the cone extends straight behind the rider (which obviously isn’t like real life, but could potentially simplify the modeling equations and data structures) since it would mean slightly less draft through corners and might explain my perception. Although two other explanations seem quite plausible: 1.) that segment is at the end of a race so things naturally string out and the perception of how strung out it is could be increased by the fact that the blob is turning sharply which shows more clearly how strung out things are so it feels like it’s different because you’re seeing a different angle, but it’s actually exactly like it always is (if you watch a pro race with a front on camera on the sprint and a drone or helicopter this effect is very obvious—from in front of or behind the riders things look more compact than they are), or 2.) it is harder there but because it’s little rolling alternations between gradients and has nothing to do with draft simulation.

I don’t know how draft is affected but curvy roads require increased power to maintain position when you’re involuntarily taking the long way around a corner, and there’s no guarantee that you’ll take the short route around the next corner.