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Turbine blade analysis [Undefined variable error]

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Hello Comsol forums,

I've been at this for several days now and can't get it to work. The idea is to model a turbine blade in a jet engine environment, and later apply a thermal barrier coating to see what the effect is on the temperature gradient.

I've followed the stator blade tutorial before, as seen here. But I decided I wanted a more accurate analysis for an actual turbine blade. I found a 3d model online of a turbine blade and imported that into comsol. After fixing some overlapping boundaries (deleting the redundant edges) the mesh generates just fine. I set a bunch of heat fluxes and variables, just like in the stator blade tutorial, but when I try to compute it it gives the following error:

Undefined variable. - Variable: comp1.T - Geometry: geom1 - Boundaries: 854, 868, 900-901 Failed to evaluate expression. - Expression: comp1.T - Plot: surf1 (Surface)

Looking at the boundaries, they're all on one side of the turbine blade. I'm not the most experienced user of comsol, so I'm not really sure what's going on here. The stator blade example worked fine.

I'm only trying to model the temperature, not the thermal stresses. That would be something I could look into later.

I wanted to attach the .mph file but even after clearing meshes and studies, and setting optimization to file size, it's too big.

EDIT: For some reason in all my selections for the boundary fluxes, it says "not applicable"? EDIT2: I might know why it doesn't work. It doesn't see the turbine blade as a domain. I can select boundaries and all but it's not a domain. If I create a normal block next to it I can then select that as a domain (it lights up, etc) but the turbine blade still doesn't. EDIT3: I added the turbine blade 3d model, the SLDPRT. Maybe someone could check it out and figure out what's wrong? Maybe a poorly made 3d model.

I made a screenshot of the faces that the error refers to: (No heat fluxes are defined on them, they're just straight from the model).



0 Replies Last Post 2020年6月16日 GMT-4 18:39
COMSOL Moderator

Hello Bas van Berkel

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