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wenbinyugroup / ivabs

iVABS is a VABS-based design framework for composite beams including helicopter rotor blades, wind turbine blades, high aspect ratio wings, etc.
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Default mesh #61

Open wenbinyu-PU opened 2 weeks ago

wenbinyu-PU commented 2 weeks ago

Based on an input file given by Sichen, it seems the default mesh is still 3-node trias. Can it change to be 6-node trias?

unitasium commented 2 weeks ago

Yes.

In prevabs input file, change "element_type" to "2" or "quadratic":

<cross_section>
  ...
  <general>
    <element_type>2</element_type>
  </general>
  ...
</cross_section>
unitasium commented 2 weeks ago

The default is "quadratic". So you can remove the line of "element_type". See the last section "Global shape and mesh settings" of the manual: https://wenbinyugroup.github.io/ivabs/ref/prevabs/contents/guide/pre_overall.html

wenbinyu-PU commented 2 weeks ago

@sichenliuPU @unitasium Su, after an experiment by Sichen, we found out that the sectional properties almost remain unchanged (less than 1% difference). However, the time is 10+ times slower. Thus, I need to correct my mistake of the default mesh. Still the default mesh should be linear elements. However, in the documentation, we need to mention that for accurate stress/strain/strength predictions, users can switch to quadratic elements. Sorry for the back and forth. The following is the VABS running time for a typical blade section reported by Sichen. linear: 0.42 secs quadratic: 5.55 secs