Originally posted by Ratchie1:
Ok,
Now, take two pipes for instance - with crush bends (not completely restricted like you people act like it is). The crush actually speeds velocity and drops the pressure.
Pressure only drops very locally at the constriction. The fact that the flow has to constrict and then expand causes energy losses which can be thought of as friction in the flow, reducing the ease by which the exhaust leaves the car.
So, NO the crush does not slow the flow at that bend, it speeds it up, and YES this is not a desirable characteristic because more upstream pressure is required to force out the exhuast at a given rate.
From the point of view of this aerospace engineer, it does not seem that crush bends would be the way to go simply because they add additional losses to the flow.
It's not rocket science!
