Why do passing trucks suck instead of blow?
Nope, it's not the first line of a joke or a rhetorical question. I would expect a passing truck or bus to be pushing a wave of high pressure air in front and beside, but I've noticed time and agai...
Forum Discussion
Vulcan Rider wrote:4X4Dodger wrote:
Sorry but the effect is the same for cars, trucks and other vehicles.
And the others are correct this is what is happening when a truck passes you.
If you are really attuned to your vehicle you will feel the initial push of the bow wave, then comes the low pressure area or feeling of being pulled in.
Once again, contradictory statements. The last one is mostly true and explains the question originally asked here. If you are being overtaken, that initial bow wave hits you in the BACK and makes you feel that you are being pushed/sucked in the opposite direction.
You really do not feel the low pressure area, hopefully, because it remains within a few inches to maybe a foot of the big vehicle in question. OUTSIDE of that area, the pressure is higher.......UNITL you get to the back where the pressure wave collapses and a vacuum is formed.
And none of that really has anything to do with the Bernolli effect.
You are right this is NOT LIFT. Using a wing and the effect of lift does not apply here.
When a truck does pass you though you will feel the "pull" of the low pressure after the turbulence of the bow wave has passed you. Keep in mind that you may feel another bow wave at the front of the trailer as it passes you, but smaller and more turbulent. But the low pressure will pull you towards the truck after that. At the end of the trailer there is yet another low pressure area right behind and caused by the trailer. This will also tend to pull you in that direction.
Again the wing analogy is completely off base here.
