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  3. Why does the adjoint solver fail with a nan-residual?

Why does the adjoint solver fail with a nan-residual?

Tagged: 19.1, Adjoint Solvers, fluent, Fluent Flow Optimization, fluid-dynamics, General
    • April 5, 2023 at 2:32 pm
      FAQFAQ
      Participant

      If the following adjoint solver residuals are shown: Computing the adjoint for observable myObservable Iter Adjoint-continuity Adjoint-xMom Adjoint-yMom Adjoint-zMom Adjoint-Flowrate Adjoint-energy 1 -nan 0.00000e+00 0.00000e+00 0.00000e+00 0.00000e+00 0.00000e+00 Invalid arithmetic operations – exiting. ! Adjoint solution is converged then you have probably applied non-constant material properties. Only the density can be defined as either a constant or a compressible ideal gas. All other fluid properties should be defined as constant.

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