Description

This project models a Venturimeter with a U-tube manometer in ANSYS Fluent to show how the manometric fluid column varies. A converging–diverging nozzle creates a pressure difference; one manometer limb taps the throat, the other the converging section. In the low-pressure region, the manometer fluid rises. A multiphase VOF framework is used.

Geometry & Mesh

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  2D geometry: built in DesignModeler.

  
  


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  Mesh: unstructured, generated in ANSYS Meshing with 42,413 elements.

  
  

CFD Simulation

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  Solver: pressure-based, unsteady.

  
  


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  Gravity: −9.81 m/s².

  
  

Models & Properties

Multiphase (VOF, homogeneous)

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  2 Eulerian phases: air and mercury

  
  


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  Interface: Sharp

  
  


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  Formulation: explicit

  
  


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  Body force: implicit body force

  
  

Turbulence

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  k–ε model

  
  

Materials

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  Air: ρ = 1.225 kg/m³, μ = 1.7894×10⁻⁵ kg/(m·s)

  
  


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  Mercury: ρ = 13,529 kg/m³, μ = 0.001523 kg/(m·s)

  
  

Boundary Conditions

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  Inlet (air): Velocity inlet, |V| = 1.8 m/s; air volume fraction = 1.

  
  


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  Outlet: Pressure outlet, gauge pressure 0 Pa; air backflow volume fraction = 0.

  
  

Numerics

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  Pressure–velocity coupling: PISO

  
  


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  Spatial discretization:

  
  
  
  
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    Pressure: PRESTO!

    
    
  
  
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    Momentum: First-order upwind

    
    
  
  
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    Volume fraction: Geo-Reconstruct

    
    
  
  
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    k, ε: First-order upwind

    
    
  
  
  
  

Initialization & Run

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  Initialization: Standard.

  
  


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  Patch: Phase = air, Variable = Volume fraction, Region = region_0, Value = 0.

  
  


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  Time step: 0.001 s; 10 max iterations/step; 1,200 time steps.

  
  

Results

A volume-fraction profile is sampled at multiple locations, and 2D contours of density, streamlines, air volume fraction, and mercury volume fraction are produced. Initially, the manometer columns are level; as flow develops, the pressure drop at the throat drives a mercury level difference between the two limbs, visualizing the pressure differential created by the Venturi.