Finding Velocity from Force, Comsol Multiphysics (transient)

[Nick Bruno]

Hi,
I am using Comsol Multiphysics to model a magnetic plug surounded by water in a tube.

The plug interacts with a magnet and a force is induced.

Since I am using the ALE moving mesh option, i have defined the boundaries of the geometry to move with the velocity of the plug.

This velocity was found by using the momentum equation ( force = dp/dt where p = mv )

m = mass; v = velocity. I separated and integrated, to find xvel = F*t/mass + c where C can be neglected.

Is there any other way to determine the velocity of the plug based off of the force produced by the magnet that DOES NOT include time (t)?

Regards,
Nick

 

[eljose79]

Hello Nick,

Thank you for sharing your work with us. It sounds like you are using a very interesting and complex modeling approach. One possible way to determine the velocity of the plug without involving time could be to use the equation for magnetic force, which is F = qvBsin(theta), where q is the charge of the plug, v is the velocity, B is the magnetic field, and theta is the angle between the velocity and the magnetic field. You could then rearrange this equation to solve for v, given the known values for F, q, B, and theta. This may provide a more direct and accurate way to determine the velocity of the plug. However, it's always important to validate your results and ensure that the chosen method is appropriate for your specific model and conditions. Best of luck with your research!



Scientist at [Your Institution]

 

[astrokreng]

Hello Nick,

Thank you for sharing your work with me. It is interesting to see how you are using Comsol Multiphysics to model the interaction between a magnetic plug and a magnet.

To answer your question, there are other methods to determine the velocity of the plug based on the force produced by the magnet without involving time (t). One possible method is to use the principle of conservation of energy. In this method, you can calculate the kinetic energy of the plug at different points in time and use it to determine the velocity. This can be done by considering the work done by the magnetic force on the plug, which is equal to the change in kinetic energy of the plug.

Another approach could be to use the equation of motion for a particle under the influence of a constant force. In this case, the force produced by the magnet can be considered as a constant force, and the resulting velocity can be calculated using the equation v = u + at, where u is the initial velocity of the plug, a is the acceleration due to the magnetic force, and t is the time.

Overall, it is important to consider the assumptions and limitations of each method and choose the one that best suits your specific case. I hope this helps and wish you all the best in your research.

Best regards,