# TAWSS AND OSI visualization in paraview

**URL:** https://discourse.paraview.org/t/tawss-and-osi-visualization-in-paraview/8650
**Category:** ParaView Support
**Created:** [December 18, 2021, 1:01pm UTC](https://discourse.paraview.org/t/tawss-and-osi-visualization-in-paraview/8650 "2021-12-18T13:01:12Z")
**Posts on this page:** 3
**Page:** 1

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### Author: ![Sumit\_Kumar](https://discourse.paraview.org/user_avatar/discourse.paraview.org/sumit_kumar/32/8227_2.png) [@Sumit\_Kumar](https://discourse.paraview.org/u/Sumit_Kumar)
#### Post date: [December 18, 2021, 1:01pm UTC](https://discourse.paraview.org/t/tawss-and-osi-visualization-in-paraview/8650/1 "2021-12-18T13:01:12Z")

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I have a question that is about post-processing using Paraview to extract time-averaged values.

For my simulations (using simvascular) of flow in the human aorta, I am currently calculating the instantaneous wall shear stress (WSS) values at the surface of the geometry.  
Now, additionally, I would like to calculate the time-averaged wall shear stress and the oscillating shear index.

![OSI WSS](https://discourse.paraview.org/uploads/default/original/2X/1/1102191ed0daf46e890d8f2e59d9a4604226f499.png)

My WSS values for every timestep are saved to a time-series .vtp and .vtu format file

In ParaView, I can access the WSS values for every timestep

I would like to average these WSS values over three cardiac cycles.

Would it be possible to use a Programmable Filter to compute the oscillating shear index (OSI) and time-averaged Wall Shear Stress (Tawss)? Perhaps, could you refer me to an example of how to use this filter for a purpose such as this?

Thank you in advance for your time.

With kind regards,

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### Author: ![pavel](https://discourse.paraview.org/user_avatar/discourse.paraview.org/pavel/32/8287_2.png) [@pavel](https://discourse.paraview.org/u/pavel)
#### Post date: [December 29, 2021, 3:41pm UTC](https://discourse.paraview.org/t/tawss-and-osi-visualization-in-paraview/8650/2 "2021-12-29T15:41:19Z")

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Hi Sumit,

For time-averaged Wall Shear Stress (Tawss), you can try existing filter ‘Temporal Statistics’. I attached two figures to illustrate it for standard ParaView dataset ‘can.ex2’.

 ![DISPL_step_13](https://discourse.paraview.org/uploads/default/original/2X/f/fd5aacb7102888657a5371e4686d149b8a1336c7.png)

 ![DISPL_average](https://discourse.paraview.org/uploads/default/original/2X/9/9841a5e1b533f99a7bd210add99a39fddfc41cf8.png)

Does this approach work for your task (I mean Tawss)? Or do you need a solution through Programmable Filter only?

Best Regards,  
Pavel

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### Author: ![Thansiya\_P\_A](https://discourse.paraview.org/user_avatar/discourse.paraview.org/thansiya_p_a/32/13154_2.png) [@Thansiya\_P\_A](https://discourse.paraview.org/u/Thansiya_P_A)
#### Post date: [September 11, 2024, 1:40pm UTC](https://discourse.paraview.org/t/tawss-and-osi-visualization-in-paraview/8650/3 "2024-09-11T13:40:22Z")

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hi pavel,  
i am working on same thing (tawss)…  
by doing the same as told here - i couldnt find the answer . can you suggest different approach/more