Kz vs. speed
Kz vs. speed
(OP)
Hi, excuse me my bad English. I would, if possible, give me your opinion on an issue:
I want to model one quarter of vehicle. The tire manufacturer provides Kz (for different pressures and camber angles), but does so for a given speed (125 Kph). I have understood that Kz varies linearly with speed and Kz increases if the speed is increased (effect of centripetal force) but what I can know how much. There any way to make a rough estimate. Knowing the type of tire, size or something else might be able to determine about this variation?
Regards
I want to model one quarter of vehicle. The tire manufacturer provides Kz (for different pressures and camber angles), but does so for a given speed (125 Kph). I have understood that Kz varies linearly with speed and Kz increases if the speed is increased (effect of centripetal force) but what I can know how much. There any way to make a rough estimate. Knowing the type of tire, size or something else might be able to determine about this variation?
Regards





RE: Kz vs. speed
Cheers
Greg Locock
New here? Try reading these, they might help FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm?
RE: Kz vs. speed
Yes, that is. The graphics I have are deflection (mm) vs. Load (Kg) for different camber angles and different pressures. Then, I have the vertical stiffness for different camber angles and different pressures, but all these plots are at 125 kph. My intention is to know, for a given pressure and camber, vertical stiffness for different speeds to 125 kph.
Kz varies linearly with speed (something like: Kz=a*V+b, b>0) and Kz increases if the speed is increased (a>0) but what I can know how much ¿? I wonder if there is any way of knowing about what is the slope of that line knowing, for example, the dimensions of the tire or the tire is radial and so on.
Regards, Roter Helm
RE: Kz vs. speed
If the graphics are deflecction (m.m) vs. Load (Kg), is not entirely correct to obtain the vertical tire stiffness( Load*9.81/deflecction) of calculating the slope of the line. The force that causes a certain deflection is the weight + the effect of centripetal force, not just weight. What do you think about this?
Regards, Roter Helm
RE: Kz vs. speed
I don't actually know where to go from here, any test in the real world is going to find it hard to differentiate between vehicle effects and tire effects.
Cheers
Greg Locock
New here? Try reading these, they might help FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm?
RE: Kz vs. speed
It could to take the stiffness constant. It´s a Formula Ford ("No Downforce"), is not critical the ground clearance.
Thank you
RE: Kz vs. speed
RE: Kz vs. speed
Sorry, I'm not sure understand you. My English is bad.
I have not the means to conduct such a test.
I love to see this video.
Regards, Roter Helm
RE: Kz vs. speed
http://www.youtube.com/watch?v=S4O7b0-epBo
http://www.youtube.com/watch?v=SgrY-LN4GUs
http://www.youtube.com/watch?v=I2o1rxMGFdI
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