Towing distance?
Towing distance?
(OP)
I would like someone to suggest the distance between vehicles to eliminate the affects of drafting so I can measure both rolling resistance and aerodynamic drag by towing a vehicle at different speeds (up to 70 mph) on flat ground.
Ed Danzer
www.danzcoinc.com
www.dehyds.com





RE: Towing distance?
RE: Towing distance?
Regards
eng-tips, by professional engineers for professional engineers
Please see FAQ731-376: Eng-Tips.com Forum Policies for tips on how to make the best use of Eng-Tips Fora.
RE: Towing distance?
Norm
RE: Towing distance?
RE: Towing distance?
Maybe have a look at:
SAE J1263 Road Load Measurement and Dynamometer Simulation Using Coastdown Techniques
SAE J2263 Road Load Measurement Using Onboard Anemometry and Coastdown Techniques
RE: Towing distance?
Ed Danzer
www.danzcoinc.com
www.dehyds.com
RE: Towing distance?
RE: Towing distance?
RE: Towing distance?
Based on one custom air pressure sensor project that I did for a NASCAR team, I know they were seeing effects at trailing distances up to 200 feet. This was behind a relatively slippery, with the exception of the rear spoiler, race car at speeds of 150 mph and up. It was quite amazing how far back behind the lead vehicle the effective air pressure was reduced.
-Tony Staples
www.tscombustion.com
RE: Towing distance?
The coast down test will have some additional power loss from the third member, drive shaft and transmission. So I think I will try the coast down method and towing with 200 feet between vehicles to see what the differences are. It might be May before I have time to do the tests but I’ll try to post the data.
Ed Danzer
www.danzcoinc.com
www.dehyds.com