Fail to build domain when particle are too small

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Fail to build domain when particle are too small

Hello !
Happy New Year !
I just wanted to ask you about an issue :
I wanted to create a domain using granoo-cooker but when I set the particle at 289e-6 which is the size of a sand particle, the cooker just stop loading.
The issue appears at e-5 and the cooker is working at e-4


Here is the whole cooker :

<?xml version="1.0" encoding="UTF-8"?>

<GranOO Version="2.0" TotIteration="Inf" OutDir="TEST" DisplayProgression="No"> 



    <PlugIn Id="_NewSupportShape" Type="Box" DimX="0.5" DimY="0.2" DimZ="0.4" ID="Boundary"/>
    <PlugIn Id="InitProblem" AverageDeRadius="289e-6" BoundarySupportShapeID="Boundary"/>
    <PlugIn Id="ComputeTimeStep"/>

    <PlugIn Id="ComputeStabilisationIterationNumber" StabCoeff="0.5"/>

    <PlugIn Id="StopFill" Criterion="Cardinality" Value="6.2"/>
    <PlugIn Id="Fill" RandomRange="17%" MaxLoopTry="10000" PacketSize="10" RepeatWhileFreePlace="Yes"/>
    <PlugIn Id="_Check"/>
    <PlugIn Id="_ClearLoad"/>

    <PlugIn Id="_ManageCollision" Between="DiscreteElement/SupportShape" UniqueId="Wall"
   BroadPhase="CustomSupportShape" RecordContactIn="WallShell"/>
    <PlugIn Id="_ManageCollision" Between="DiscreteElement/DiscreteElement" UniqueId="LCM"
       BroadPhase="CustomLcm" RecordInterpenetrationValues="Yes"/>
    <PlugIn Id="DisplayInfo" IterLoop="200"/>

    <PlugIn Id="_SaveDomain" FileName="CompactDomain" Type="gdd"/>
    <PlugIn Id="_SaveDomain" FileName="CompactDomain" Type="agdd"/>
    <PlugIn Id="_SaveDomain" FileName="CompactDomain" Type="lgdd"/>

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Re: Fail to build domain when particle are too small

Damien André
Hello, I guess that your sample is not possible to be created. The ratio between your bounding volume and the size of your element is too high. Please take a look at this simple calculation.

- Your bounding box 'V' is : V = 0.5*0.2*0.4 =  0.04 m^3
- The average volume 'v' of your discrete element is  : v = (4./3.)*pi*(289e-6)^3 ≈ 1.e-10
- So to fill your bounding volume you need v/V ≈ 400e6 of discrete element !

It is not reasonable. The cooker is  able to produce 100,000 elements... not really more

Kind regards, Damien