Hi Folks,
is there any possibility to consider the surface roughness in the calculations? I am trying to validate a conic press fit, where the surface roughness plays an important role in calculating the oversize. Probabily because of the missing roughness I get much bigger forces and deviations with PrePoMax than with hand calculations.
Surface roughness is usually modeled by generating random or structured surface deformations or applying them from point clouds from 3D scans. The result is something like this:
From “Analysis of the Contact Area of Smooth and Rough Surfaces in Contact with Sphere Indenter Using Finite Element Method” by Kartini et al.
So you would need an external code to generate the rough surface geometry.
Is harder than i thought. However I found an another approach. I will calculate without roughness, but smaller oversize, like in this formula:
Yeah, I would also choose a simplified analytical approach in such a case. Surface roughness modeling is not needed in most cases apart from research purposes.
surface roughness is related to tangential force transmitted, so it’s a Coulomb friction coefficient in contact analysis.
Not directly, but that could be another approximation.
Coulomb friction coefficient tested and provide different type of material including stone and steel, so my understanding in roughness are directly correlated.
What I meant is that the friction coefficient is not a measure of surface roughness. But it depends on that and there are some studies regarding this: https://www.researchgate.net/profile/N-Parthasarathi/publication/284947607_Correlation_between_coefficient_of_friction_and_surface_roughness_in_dry_sliding_wear_of_AISI_316_L_N_stainless_steel_at_elevated_temperatures/links/5f61adef299bf1d43c0768ed/Correlation-between-coefficient-of-friction-and-surface-roughness-in-dry-sliding-wear-of-AISI-316-L-N-stainless-steel-at-elevated-temperatures.pdf
However, when talking about modeling surface roughness, we usually mean the approach with rough surface geometry.
ussually explicit models of surface roughness in geometry have a purpose to validated friction coefficient value approach.
https://www.researchgate.net/publication/352117646_Static_friction_at_fractal_interfaces
