Quote:
Originally Posted by aerohead
I catch ---- for saying it, but your nose is probably already 'saturated.' There's a point where further modification will cease to deliver any additional drag reduction.
If this canopy graphic shows, you'll see that there's no Cd difference between the 'blunt' and more aircraft nose-like bubble canopy.
https://ecomodder.com/forum/showthre...rag-28206.html |
Ahh. If we are talking about abstract contiguous contours used as noses, then I completely agree with you that there are a wide range of different shapes that produce effectively equivalent drag.
But, if we are talking about real world cars, there is tremendous opportunity for improvement. The lead order of drag near the nose of a vehicle is the
airflow through the radiator system. That has several distinct opportunities to decrease power loss:
1) The air inlet (say, reducing pressure / area that forces work over)
2) The radiator itself (say, by decreasing pressure drop / friction across it)
3) The airflow pathway (say, by using smooth ducting both in and out)
4) The air outlet (say, by matching steady state vector velocity and pressure)
Moreover, both theoretical calculations and actual mods racers make show this improvement is in excess of +20% fuel economy. That's equivalent to a well made and designed boat tail.
So I must disagree that the nose is already "saturated." It seems to me that you've mistaken the ideal airflow
around a contour with the reality of airflow
through a radiator. That's a big mess because air is being extracted, its properties changed, and then reinjected into the airflow through the vehicle envelope. Which further means comparisons to contours with sealed envelopes fails to capture the complexity of what's actually going on.
But the proof is in the pudding. I'll mod up the nose, post the results, and then we can see whether it was actually worth doing or not. Sound reasonable?