Quote:
Originally Posted by Vman455
Forgive my exasperation, but I spent 4 hours, including the trip to the hardware store for materials to mount the pitot tube in freestream air above the car when my first apparatus failed, out of my very busy schedule (full-time job, half-time in school, and teaching part-time at another school) gathering this data only for you to chime in with your opinion that it is worthless, as you have criticized JulianEdgar on this forum before in an attempt to discredit any sort of on-road testing, even stooping to personal attacks as recently as this very afternoon. I don't know what axe you're trying to grind here; I don't think it is worthless, and if adding the spoiler lip has increased pressure under the car--well, I'll be measuring that soon and doing what I can to mitigate it.
|
Keep doing your testing - I think your results are great, and we will all be able to learn a lot from them. In fact, you might want to think of keeping a Word doc with all your results in it - so much easier to refer back to than miscellaneous forum posts.
As for Aerohead, I have avoided the personal belittlement he is fond of, but it's obvious he has some issues. There's a lot of confusion in what he writes, and as you have previously found, many of the references that he cites don't actually support what he claims. However, I think the worst thing is that he refuses to learn from developments of the last 20-30 years and so keeps on rehashing the same old (mis)information.
Of course he isn't going to like your testing, because (as with mine) it will so quickly show that much of what he says is simply wrong!
Pressure and tuft testing tell you so much, and when you add lift/downforce testing, you'll be looking at information radically better than any guesswork / rules of thumb / 1930s models / templates, etc. (And, I'd also argue, a lot better than crappy CFD.)
Re using other height sensing techniques, I have tried ultrasonic height detection but couldn't get the resolution needed for lift/downforce testing at normal road speeds. So back to a simple P38 Range Rover analog pot-based sensor. I think my latest smoothing circuit is better than the one in my Veloce book, and seemed to work really well on the Impreza rear wing / spoiler tests.
So keep testing - it certainly takes time and effort, but it's also like taking off a blindfold and seeing the world for the first time.