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  3. Convergence of User Defined Scalar

Convergence of User Defined Scalar

Tagged: fluent, fluid-dynamics, General, General - FLUENT, Other
    • January 25, 2023 at 7:16 am
      FAQFAQ
      Participant

      There might be a need to solve for User Defined Scalar(UDS) in Fluent. It has been found that in some instances, using zero diffusivity for UDS leads to NAN. Also, first-order discretization results in diverging of the run after initial convergence. Following suggestions might help in overcoming the problem. 1) Instead of zero diffusivity, use a very small number, say, and 1e-12. 2) Use double precision solver. 3) Importantly “power law” discretization helps in overcoming divergence of UDS equation.

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