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Multiphase Flows

Multiphase Flows

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  3. What is the meaning of “…warning: …Pressure …less than down-stream pressure -1, or Invalid downstream density -1 Skipping injection…” for a Pressure-swirl atomizer? How to resolve this issue?

What is the meaning of “…warning: …Pressure …less than down-stream pressure -1, or Invalid downstream density -1 Skipping injection…” for a Pressure-swirl atomizer? How to resolve this issue?

Tagged: fluent, fluid-dynamics, MP - Particle Tracking, Multiphase; Particle Tracking, Spray/Break-up Models
    • March 17, 2023 at 8:59 am
      FAQFAQ
      Participant

      Atomizers need an initial guess of downstream pressure/density. For that Fluent calculates the virtual origin based on Position (x,y,z), Injector Inner Diameter and Spray Half Angle. This point is used for evaluating an initial guess of downstream pressure/density. If this virtual origin is found outside of the domain you will get the warning message reported. If you move the center point of your atomizer (X,Y,Z-Position) slightly into your domain, the warning disappears and the particles are injected as intended.

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