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how to set an input variable that is the function of a valuable solved in the time dependent simulation?
Posted Jun 5, 2014, 3:25 p.m. EDT Mesh, Structural Mechanics Version 4.3 2 Replies
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Hi,
I am working with an elastic structure which was influenced by some known forces and an unknown force. This force (damping) is actually proportional to the velocity of a specific point on the structure. The initial condition is given in this case. Since the structure is deformed and moving under the influence of all the forces, Comsol can get the velocity of that specific point through simulation and therefore get that unknown force for that moment. And then it can goes on for the next time step with the calculated force. How can I set this input force? How can I set an definition of that unknown force with the velocity(changing with time) of that specific point?
Can you help me with this? Thanks soooooooooooo much!
Best,
Ting
I am working with an elastic structure which was influenced by some known forces and an unknown force. This force (damping) is actually proportional to the velocity of a specific point on the structure. The initial condition is given in this case. Since the structure is deformed and moving under the influence of all the forces, Comsol can get the velocity of that specific point through simulation and therefore get that unknown force for that moment. And then it can goes on for the next time step with the calculated force. How can I set this input force? How can I set an definition of that unknown force with the velocity(changing with time) of that specific point?
Can you help me with this? Thanks soooooooooooo much!
Best,
Ting
2 Replies Last Post Jun 10, 2014, 7:32 p.m. EDT
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Posted:
1 decade ago
Hi Ting,
You can use 'at1', 'at2' or 'at3' to refer to a value at a specific point in your geometry (1, 2 and 3 refer to the spatial dimensions in your model). So for example if you have a 3d geometry and the displacement is given by u then you would find the X-component of the velocity at point (x,y,z) by at3(x,y,z,u_tX). This expression you can use to define your force.
You can use 'at1', 'at2' or 'at3' to refer to a value at a specific point in your geometry (1, 2 and 3 refer to the spatial dimensions in your model). So for example if you have a 3d geometry and the displacement is given by u then you would find the X-component of the velocity at point (x,y,z) by at3(x,y,z,u_tX). This expression you can use to define your force.
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Posted:
1 decade ago
Thanks so much! :-)
Best,
Ting Zhou
Best,
Ting Zhou