Question #672525 on Yade changed:
https://answers.launchpad.net/yade/+question/672525
Status: Answered => Open
Xiaohu Tao is still having a problem:
Hi, Jérôme
Thank you so much for the detailed explanation.
I read the background of yade. Can I understand in this way? "U" is the
position, U(0) is the position at Iter 0, U(1) is the position at Iter
1, and U(2) is the position at Iter 2. "V" is the mean velocity and "a"
is the acceleration. in my code a=gravity. △t=1, U(0)=(0,0,0)
So
V(1)=V(0)+a*△t while "V(0)=0", V(1)=(0,0,-9.81)*1=(0,0,-9.81), this is
just the mean velocity, NOT the instantaneous velocity at time 0+△t
U(1)=U(0)+V(1)*△t=(0,0,0)+(0,0,-9.81)*1=(0,0,-9.81)
V(2)=V(1)+a*△t =(0,0,-9.81)+(0,0,-9.81)*1=(0,0,-19.62)
U(2)=U(1)+V(2)*△t=(0,0,-9.81)+(0,0,-19.62)=(0,0,-29.43)
------------------------------------------------------------------------------------------------------------------------
In my understanding：(1) the value of V(0)=0 is the key of the error,
so the error is formed in the first iter. (2) the velocity showed by
yade is the mean velocity in one iter.
Xiaohu
--
You received this question notification because your team yade-users is
an answer contact for Yade.
_______________________________________________
Mailing list: https://launchpad.net/~yade-users
Post to : [email protected]
Unsubscribe : https://launchpad.net/~yade-users
More help : https://help.launchpad.net/ListHelp
