D Jones Posted October 11, 2016 Share Posted October 11, 2016 Has anyone confirmed the 0-60 and high speed advantages of going aero, or is it all based on "feeling".logic suggests that the reduced surface area should allow the car to cut through the air and I don't suppose Caterham would have put the car in a wind tunnel..........would they?any thoughts........david Link to comment Share on other sites More sharing options...
tweeky Posted October 11, 2016 Share Posted October 11, 2016 I found I needed to use the brakes more after going aero........the windscreen is a great airbrake. Link to comment Share on other sites More sharing options...
DJ. Posted October 11, 2016 Share Posted October 11, 2016 I wouldn't think the 0-60 changes much, but over 80 it must make a huge difference. Link to comment Share on other sites More sharing options...
Paul 160 Posted October 11, 2016 Share Posted October 11, 2016 These scans from 2001 have been linked to a few times. It's an interesting read about a Caterham being put in a wind tunnel:http://californiacaterhamclub.com/aerodynamic/Caterham%20aero%20art%201%20copy.jpghttp://californiacaterhamclub.com/aerodynamic/Caterham%20aero%20art%202%20copy.jpghttp://californiacaterhamclub.com/aerodynamic/Caterham%20aero%20art%203%20copy.jpgPaul. Link to comment Share on other sites More sharing options...
tweeky Posted October 12, 2016 Share Posted October 12, 2016 And the finished item :- http://uk.caterhamcars.com/sites/default/files/styles/slideshow/public/cars/slideshow/cars-header-main-caterham-aeroseven-concept-2_1.jpg?itok=vJ3ud4Uu Link to comment Share on other sites More sharing options...
D Jones Posted October 13, 2016 Author Share Posted October 13, 2016 So to summarise, it is based only on feeling with no evidence to substantiate people's thoughts. Link to comment Share on other sites More sharing options...
aerobod - near CYYC Posted October 14, 2016 Share Posted October 14, 2016 At 160km/h / 100mph the windscreen on an S3 creates about 400 Newtons of drag, with the aeroscreen and two helmeted occupants, likely 2/3 of that drag force can be removed. You can definitely feel the difference in drag at higher speeds. I estimate the total drag at 100mph is not much more than 1000N, so an aeroscreen equipped car has only about 3/4 of the drag of a windscreen equipped car. Link to comment Share on other sites More sharing options...
Dr Slotter Posted October 14, 2016 Share Posted October 14, 2016 And that is because it has about 3/4 of the cross-sectional area normal to the flow. Link to comment Share on other sites More sharing options...
Tom_Arundel Posted October 14, 2016 Share Posted October 14, 2016 At Marham a couple of years ago my 125 did 112mph at the end of the straight with full screen and 120mph with my version of an aero screen. acceleration above 60 is noticeably better but no figuresWell worth doing if you don`t mind a bit of gravel and being pelted at low speeds when it rains ! Link to comment Share on other sites More sharing options...
aerobod - near CYYC Posted October 15, 2016 Share Posted October 15, 2016 The drag for a given body is proportional to the cross-sectional area, but a vertical plate has a Cd of 1.28, the slight inclination of the windscreen will make it slightly less than this, whereas the Caterham body will be somewhere closer to 0.7, so not quite just the effect of frontal area. Also, the drag with the roof on will be mainly affected by changing the windscreen from a flat plate to a bluff body from an airflow perspective, dropping the Cd of the windscreen/roof combination closer to 1.00. A flat plate is the worst profile for drag due to the severe vortices created and separation of flow as the air tries to wrap around the edges. Link to comment Share on other sites More sharing options...
Leadership Team Shortshift Posted October 15, 2016 Leadership Team Share Posted October 15, 2016 There is a Pistonheads thread on this, from a few years ago, where someone posted the effects on acceleration and top speed of running with windscreen and then with aeroscreen. I recall the delta being quite significant. Maybe worth a quick search?James Link to comment Share on other sites More sharing options...
Alan Archer Posted October 15, 2016 Share Posted October 15, 2016 A little bit of info found on PH.Alan Post on behalf of a friend.... In an SLR, how much of a difference do you notice in acceleration terms when the standard screen is removed and replaced with an aeroscreen? Even though the aero jobbie has a slight lip to direct the airflow higher than the drivers ribcage, how much buffeting do people experience? Also, is it advisable to wear a helmet when going sans full screen? (in preference to just goggles)? Thanks all. PS What do 120mph flies taste like?L100NYY32,736 posts153 months[report] [news] Thursday 17th June 2004 I would advise that you/he wears a helmet on the road as it only takes an errant stone (or big fly) to do some serious damage (trust me, I know)! Nothing beats the feeling of blatting a Seven on the road with the aeroscreen although I reccommend the interchangeable aeroscreen that Caterham produces as this gives the best of both worlds. The only difference you will feel acceleration wise will be the extra noise with an aeroscreen!!!charlie_pank3 posts170 months[report] [news] Thursday 17th June 2004 You get to hear the induction noise much better too. A lovely rush of air from the intake just in front of you when you put your foot down.dino ferrana789 posts162 months[report] [news] Thursday 17th June 2004 Driving with an aeroscreen is like a whole different world. The car is faster (equivalent to 20-30 bhp at 100 mph) and feels much faster as well. The whole experience is more exciting and more involving. There is less buffeting with an aeroscreen than with a windscreen without the sidescreens on. I recommend you wear sunglasses at the very minimum when driving with the aeroscreen. A helmet is necessary for rainy days and makes long trips more comfortable.mav the wibbler34 posts149 months[report] [news] Thursday 17th June 2004 equivalent to 20-30 bhp at 100 mph From where do you get this information Dino?? Advertisementdino ferrana789 posts162 months[report] [news] Friday 18th June 2004 Mostly I make it up! I have heard this said many times and having had a screen on my superlight and then removed it I believe it! On track the acceleration at high speeds is much improved.mav the wibbler34 posts149 months[report] [news] Friday 18th June 2004 You should try with a screen and hood. My car takes off like a scalded cat at 80+mph with the hood fitted. Must be worth the same 20 - 30 bhp - Oh and with the hood up there is much more noise so it must be faster >> Edited by mav the wibbler on Friday 18th June 16:12mikeww155 posts167 months[report] [news] Friday 18th June 2004 OK, my opinion for what it's worth. On the track an aeroscreen is noticeably quicker especially above about 80 and well worth it. On the road you will not really notice any performance improvement.I know some people like them for the road but I would much prefer a windscreen everytime.Personally I feel far too vulnerable and as soon as you use a helmet then you loose all the 'wind in your hair' benefit. Rain hurts! MikeWmav the wibbler34 posts149 months[report] [news] Friday 18th June 2004 I'll be aeroscreening my SV for Track use only - Windscreen every time for the road for medroid42121 posts163 months[report] [news] Saturday 19th June 2004 Dino, You weren't that far off ... it's worth 18bhp at 100mph. For a 170bhp'ish car, an aeroscreen adds around 15mph top speed. Ian.Purple Cat26 posts165 months[report] [news] Tuesday 22nd June 2004 My 1.8 Supersport(cica 150bhp) would hit the rev limmiter in 5th(top) with the aeroscreen which was an indicated 135 on the clock but would only get to 120 with the screen and not reach the limiter. It also went round to 120 very quickly with the aero where as with the screen at 80 ish the screen acts as a wind brake and slows the car,I never timed the difference but would hassard a guess that the 0-100 time dropped buy as much as 3 to 4 seconds, well it felt like it anyway. I only wore a helmet on motorways and when it was raining or at night, but I did invest in a pair of tough sun glasses. I always kept a good gap from the car in front. If the car is not going to be used for touring I would highly recommend an aeroscreen, saying that I took mine on a few 3 and 4 day trips to France and had no regrets. As for the flies they tend not to touch the sides so taste is not a consideration, a bee on the other hand much more fun when it is in your passengers mouth but they don't seem to mind being spat out. Pesmo149 posts149 months[report] [news] Sunday 11th July 2004 Is it possible to buy a GRP aeroscreen that where you don't need to remove the wiper motors, or do you need to do that with all aero's ? If you can buy one who makes it ? Link to comment Share on other sites More sharing options...
Leadership Team Shortshift Posted October 15, 2016 Leadership Team Share Posted October 15, 2016 Interesting, and I've just found the thread that I was referring to. Actually, it's more complex than I had recalled because it's talking about the effect of changing the airbox (on a R500D) as well as switching between standard windscreen and aeroscreen. Still, interesting to read and it's here:http://www.pistonheads.com/gassing/topic.asp?h=0&f=101&t=881648 Cutting to the chase, a summary post towards the end of the thread is as follows: OK, I was at Woodbridge airfield yesterday and I gathered some data. Peak speeds (GPS calibrated) on the long straight were 125.5mph with the trackday airbox and full screen, and 132.2mph with the foam filter and aeroscreen. The main straight is 605 metres, so I put all of this in the sausage machine to come to the conclusions that: Airbox is worth 9.5% more power, approximately 20-25bhp. Aeroscreen is worth 5kg weight saving, and reduces drag 15%. (When I say drag, I am looking at CdA.) To compare some stats of the two cars: Caterham R500 Aeroscreen/Foam Filter Full Screen/Trackday Airbox Top Speed 150mph 137mph 0-60mph 2.8s 3.1s 0-100mph 6.2s 7.1s 70-100mph 2.7s 3.2s 100-125mph 4.0s 5.7sThis is all with a basic physics model I've made in Excel, so things won't be perfect but I think it should be a reasonably accurate comparison of the before and after. James Link to comment Share on other sites More sharing options...
D Jones Posted October 16, 2016 Author Share Posted October 16, 2016 Gents, thanks for the inputs and your time answering my question, makes for some interesting reading.i have the Caterham aeroscreen on my SV and love it. Link to comment Share on other sites More sharing options...
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