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specify Volume fraction and mass fraction

    • vikash0603
      Subscriber

      Dear all,

      I am using the eulerian multiphase and species, transport model. My concern is to specify the value of species volume mass fraction and multiphase volume fraction at the inlet ( water inlet at left), inlet 2 (glycerin inlet at right). Additionally, while patching, I want to keep the fraction of water and Glycerin both 0.1 in the porous zone to converse the solution. I am attaching the (.PNG) file. Kindly look into it, and help me specify the value. 

      I used a volume fraction of 0.9 at both inlets and a mass fraction of water 1 at the left inlet, mass fraction of water 0 at the right. inlet. I ran the simulation and found a floating-point error.

      Kindly also specify the value of volume fraction during patching

    • Rob
      Forum Moderator
      Staff aren't permitted to open or download attachments so please repost the pictures.
      Are the water and glycerin different phases? Or different species in the same phase?
    • vikash0603
      Subscriber

    • vikash0603
      Subscriber
      Dear Rob,
      Glycerin and water are different phases (wetting phase), but in our case , only one one wetting phase is allowed, So I chose species transport combining water and glycerin as one phase. Later mass fraction of each can be assigned at inlets.
    • DrAmine
      Ansys Employee
      Water and glycerin are modeled as multicomponent flow: if yes then please disable Multiphase Model and stick to species transport.
    • vikash0603
      Subscriber
      Dear DrAmine,
      Water and glycerin is modeled in the mixture templates of species transport. The multiphase model is the base of my model
    • DrAmine
      Ansys Employee
      Okay I understand: what is now the question or which problems are you facing?
    • vikash0603
      Subscriber
      I am using the eulerian multiphase and species, transport model. My concern is to specify the value of species volume mass fraction and multiphase volume fraction at the inlet ( water inlet at left), inlet 2 (glycerin inlet at right). Additionally, while patching, I want to keep the fraction of water and Glycerin both 0.1 in the porous zone to converse the solution. I am attaching the (.PNG) file. Kindly look into it, and help me specify the value.
      I used a volume fraction of 0.9 at both inlets and a mass fraction of water 1 at the left inlet, mass fraction of water 0 at the right. inlet. I ran the simulation and found a floating-point error.
      Kindly also specify the value of volume fraction during patching.

      Kindly go through earlier post
    • DrAmine
      Ansys Employee
      That value should be a user input: what is the state at start? Same applies at the boundaries: do you have in reality 90% Volume Fraction? Is it correct to assume pure water at one inlet and no water at the other?
    • DrAmine
      Ansys Employee
      Do you require multiphase model at all? Do you have pure gas or pure liquids or both states in the system?
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