Quote:
Originally Posted by Dieselguru
Seeing how this is my first post, I'll try not to overstep my welcome.
Tre - It would be very interesting to see some of the runs you have done at a little higher speed, say 75 mph (the speed I drive my 110 mile round trip to work every day). If there are gains to be had, they they will show up faster at those speeds. Especially things like VG's.
As a side note: probably the reason most people don't see much improvement using VG's is that
1. VG effectiveness increases with speed (need a seperation point, otherwise its just drag)
2. VG placement probably depends very closely on speed (location of seperation point)
Look very closely at the Mitsu report on VG's. In the test setup section (page 2), they mention the baseline speed of 50 m/s (111 mph). if tre's settup is correct, will the seperation point move forward with increasing velocity to somewhat match that of the Lancer (wont be exactly the same, but simular), and will the VG's will become more effective?
Tre - if you still taking requests, through higher speeds into the mix and see what happens to some of your results.
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I believe that once the car hits a Reynolds Number of 500,000 the boundary layer goes turbulent,the Cd is established and remains a constant,and what ever flow patterns exist,exist for the remainder of the velocity spectrum until the car reaches about about 250-mph,where compressibility becomes an issue.I don't believe the separation point moves at all.Power saved by the VGs will very as the cube of the velocity,so certainly,as the velocity increases,their benefit becomes more apparent.