Are negative stresses tensile

cmroper · May 19, 2020, 18:00

This seems fairly simple but due to my background, I am used to seeing negative stresses as compressive. However, when I am using solidDisplacementFoam I get a negative stress where I would expect a positive one. Does anyone know if the negative values for sigma in solidDisplacementFoam are tensile or compressive?

tas38 · May 20, 2020, 12:51

Negative values of stress indicate a state of tension in solidDisplacementFoam. In the attached figure, solidDisplacementFoam has been used to simulate the NAFEMS-10 validation case. You can look here...

https://www.sharcnet.ca/Software/Aba...mk/default.htm

for the case setup in order to interpret the stress contour map.

cmroper · May 20, 2020, 15:46

Thanks so much for your answer tas38. Do you know if there is a simple way to flip this data so that negative values are compression?

tas38 · May 20, 2020, 16:07

If it is just a matter of post-processing, the signs on the stresses can be changed within Paraview. You can use the 'calculator' filter and multiply the stresses by -1 (and create new/modified stresses) as needed.

May 19, 2020, 18:00	Are negative stresses tensile	#1
cmroper New Member Christopher Roper Join Date: May 2020 Posts: 5 Rep Power: 6	This seems fairly simple but due to my background, I am used to seeing negative stresses as compressive. However, when I am using solidDisplacementFoam I get a negative stress where I would expect a positive one. Does anyone know if the negative values for sigma in solidDisplacementFoam are tensile or compressive?

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May 20, 2020, 15:46		#3
cmroper New Member Christopher Roper Join Date: May 2020 Posts: 5 Rep Power: 6	Thanks so much for your answer tas38. Do you know if there is a simple way to flip this data so that negative values are compression?

May 20, 2020, 16:07		#4
tas38 Senior Member Troy Snyder Join Date: Jul 2009 Location: Akron, OH Posts: 220 Rep Power: 19	If it is just a matter of post-processing, the signs on the stresses can be changed within Paraview. You can use the 'calculator' filter and multiply the stresses by -1 (and create new/modified stresses) as needed.