Can A Car Produce A Tunnel Boom?

Question

I Know high-speed trains can, but can cars produce the same affect? Especially as some have a top speed HIGHER than that of a high-speed train.

Answer 1

No.

Answer 2

Yes, for the reason that the air displaced by the motion of ANY vehicles move has to go SOMEWHERE/pressurise. Tunnel boom is SIMILAR, but not the same as a sonic boom.

Stand close to any vehicle, and you'll feel that vehicle's "wash". The vehicles wash is air being pushed around the vehicle. The air pressure is higher next to to the car, and slightly lower behind the car.

If the vehicle is going through a tunnel then there's less area for the wash to dissipate/flow and so you get higher pressure.As trains run on tracks, they usually have less clearance between the vehicles body, and the tunnel wall, making for a higher pressure. To get the highest pressures, you would only have a minimal clearance between car. and wall but that would make keeping the car going a straight line difficult, as it higher pressure at the front of the car, and the lower pressure at the rear, would tend to turn the car.

I think the frequency of the sound produced would be closely related to the vehicles speed divided by length, (as that's the reciprocal of the time it takes for the vehicle to pass)

Not sure how to estimate the intensity of the sound. I think you'd have to calculate the pressure in-front of the car and the pressure behind the car. that would need you to figure out how easily air flows through gap between vehicle and tunnel walls. You're also dealing with compressible flow (just like when working with supersonic speeds), so the equations become a LOT more complex.