trixi-framework / trixi-framework/TrixiParticles.jl

structure-fluid smoothing length and search radius are not the same

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bug
Dominant language
Julia
Stars
83
Forks
24
Avg merge
8d 18h
Merged PRs (30d)
3

Description

In structure-fluid interaction, the kernel and smoothing length of the fluid is used:
https://github.com/trixi-framework/TrixiParticles.jl/blob/c70f70a484d0d8ba8f39c99846812340b09df7fa/src/schemes/structure/total_lagrangian_sph/rhs.jl#L107-L110

However, the compact support and hence the search radius for this interaction depends on the boundary model kernel:
https://github.com/trixi-framework/TrixiParticles.jl/blob/c70f70a484d0d8ba8f39c99846812340b09df7fa/src/general/semidiscretization.jl#L189-L193

This causes incorrect kernel truncation if one uses a smaller smoothing length for the boundary model than for the fluid.

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Research direction

Start with the referenced interaction code in src/schemes/structure/total_lagrangian_sph/rhs.jl at lines 107-110 and the search-radius logic in src/general/semidiscretization.jl at lines 189-193. Trace how the fluid and boundary-model kernels and smoothing lengths determine support, then verify that a smaller boundary smoothing length does not truncate the structure-fluid kernel incorrectly.

Written by the indexing model from the issue text.

Assessment

Tech stack
julia
Domain
hpc
Issue type
Bug
Difficulty
4/5
Estimated time
3-5 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
45/100

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