If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below. |
|
|
Thread Tools | Display Modes |
#1
|
|||
|
|||
Angular acceleration and rolling resistance
> Concerning the other posts: There is indeed a change in rolling
> resistance with slip angle. Also with slip ratio. The example of an > IndyCar losing speed doesn't have much to do with that, though. > That's induced drag caused by the component of the lateral force > pointing rearwards because there's a slip angle, which slows the car > down. I assume aerodyanmic drag is also increased by the overall slip angle. Perhaps this is why the tires used on Indy and the former Champ and Cart race cars are so stiff compared to the tires used on other racing cars. The "working" (max g turn) slip angle is about 2 degrees (I think "working" slip angle means the total yaw angle of the car versus the direction the car is going, essentially the slip angle of the rear tires). |
Ads |
#2
|
|||
|
|||
Angular acceleration and rolling resistance
On Jan 29, 5:40*pm, "jeffareid" > wrote:
> > Concerning the other posts: *There is indeed a change in rolling > > resistance with slip angle. *Also with slip ratio. *The example of an > > IndyCar losing speed doesn't have much to do with that, though. > > That's induced drag caused by the component of the lateral force > > pointing rearwards because there's a slip angle, which slows the car > > down. > > I assume aerodyanmic drag is also increased by the overall slip angle. > Perhaps this is why the tires used on Indy and the former Champ and > Cart race cars are so stiff compared to the tires used on other racing > cars. The "working" (max g turn) slip angle is about 2 degrees (I > think "working" slip angle means the total yaw angle of the car versus > the direction the car is going, essentially the slip angle of the > rear tires). Yes, the drag will change with vehicle sideslip angle, but I'm not sure in which direction it goes on an Indycar over that first few degrees. I saw one aero CFD test that showed a very slight increase in front downforce on a formula style car (I was late to the lecture so don't know what kind of car it was exactly). The vertical fins in the front wing were designed to produce that increased downforce with slip angle, interestingly enough, by getting rid of a little low air pressure bubble that (simulation-wise at least) developed behind and to the outside of the front wing. What happens to drag I don't know. It's possible it increases a bit on some cars and decreases on others. On a GT car with a spoiler you can wind up with quite a bit less downforce, but it's probably not safe to say that the drag would also decrease along with it. Different cars, different effects... |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
Angular acceleration and rolling resistance | Todd Wasson | Simulators | 0 | January 26th 09 04:18 PM |
Angular acceleration and rolling resistance | Zach[_2_] | Simulators | 6 | January 25th 09 04:23 AM |
resistance readings | alkynova | Technology | 1 | November 12th 05 06:41 PM |
92 Accord has no power on acceleration / slow acceleration | zdrepaul | Honda | 0 | April 21st 05 09:29 PM |