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Peristalsis wave in 2D

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Hi,

I am having a problem to simulate a peristalysis wave in 2D. So, I have followed this example below

https://www.comsol.com/model/peristaltic-pump-985

However, this example is done using 2D axisymmetric and I want to use 2D spatial. I believe that the 2D axisymmetric uses cylindrical coordinates system which is different to 2D spatial. So, I converted all the r varibles to x and the z variables to y. Howver, the results do not match for the wave.

Kindly check the below snapshots. For the Wave_spatial, I am unable to control the width and the amplitude of the wave. May I know how do I achieve a similar result as the one achieved in the axisymmetric?

I have defined the Analytic function as below for 2D spatial

flc2hs(t_off/dt-ts,1)flc2hs(ts-t_on/dt,1)exp(-(ys-(y0+v0tsdt)/width)^2/2)

I have tried changing parameters but whatever I try, i am unable to achieve the result of that in the 2D axisymmetric wave form.

Thank you very much in advance!

Best regards, Shannon



2 Replies Last Post 06.04.2021, 07:28 GMT-4
Robert Koslover Certified Consultant

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Posted: 3 years ago 05.04.2021, 18:48 GMT-4
Updated: 3 years ago 05.04.2021, 18:49 GMT-4

You are modeling literally two different physical problems. One has axial (rotational) symmetry. The other has translational symmetry (in/out of the page). So, wouldn't it be more surprising if the plotted results were the same? Anyway, if you think one of them is wrong, which one? Why? Maybe both are wrong? Maybe both are correct? Anyway, if you need help with either model, I suggest you post the model(s) to the forum to allow more careful review by others.

-------------------
Scientific Applications & Research Associates (SARA) Inc.
www.comsol.com/partners-consultants/certified-consultants/sara
You are modeling literally two *different* physical problems. One has axial (rotational) symmetry. The other has translational symmetry (in/out of the page). So, wouldn't it be more surprising if the plotted results were the same? Anyway, if you think one of them is wrong, which one? Why? Maybe *both* are wrong? Maybe *both* are correct? Anyway, if you need help with either model, I suggest you post the model(s) to the forum to allow more careful review by others.

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Posted: 3 years ago 06.04.2021, 07:28 GMT-4

Thank you very much for your reply. I thought that I could use parts of the given example to model the peristaltic wave. My research requires me to use 2D spatial geometry and simulate a moving peristaltic curve as later the procedure has to be applied to an asymmetric geometry in 2D. Therefore,I am looking to control the amplitude width and speed of the peristaltic moving wave. 

Any help woud be greatly appreciated

below are the models. I am using comsol 5.5 https://drive.google.com/drive/folders/1sidPnKoU4-vi7pxtCRW2t3J5ztHFSk7P?usp=sharing

Best regards, Shannon

Thank you very much for your reply. I thought that I could use parts of the given example to model the peristaltic wave. My research requires me to use 2D spatial geometry and simulate a moving peristaltic curve as later the procedure has to be applied to an asymmetric geometry in 2D. Therefore,I am looking to control the amplitude width and speed of the peristaltic moving wave.  Any help woud be greatly appreciated below are the models. I am using comsol 5.5 https://drive.google.com/drive/folders/1sidPnKoU4-vi7pxtCRW2t3J5ztHFSk7P?usp=sharing Best regards, Shannon

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