Six settling disks in a FENE-CR fluid: L=5


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Six sedimenting disks form two chains after drafting, kissing and chaining, which is different from the well known phenomenon called drafting, kissing and tumbling for disks falling in Newtonian fluid. In the FENE-CR model, the polymer extension limit is set to be L=5 in the function f(C)=L*L/(L*L-tr(C)) where C is the conformation tensor. The viscoelastic fluid with a shorter polymer extension limit can not hold all six disks together.