Class InletDeviceModel

java.lang.Object
neqsim.process.equipment.separator.entrainment.InletDeviceModel
All Implemented Interfaces:
Serializable
public class InletDeviceModel extends Object implements Serializable
Models inlet device performance for separator and scrubber design.

The inlet device is the first separation stage in a separator. It performs two functions:

  1. Bulk liquid separation — removes the liquid film and large droplets from the incoming two-phase mixture.
  2. DSD transformation — changes the downstream droplet size distribution through coalescence (beneficial) and/or re-atomization (detrimental).

This class models six common inlet device types from the open literature:

Inlet device types and their characteristics from open literature
Device Bulk Eff. DSD Effect Momentum Rating Reference
No device (pipe entry) 0% None Low —
Deflector plate 50-70% Moderate coalescence Low Arnold and Stewart (2008)
Half-pipe (diverter) 60-80% Moderate coalescence Medium Arnold and Stewart (2008)
Inlet vane distributor 70-85% Good coalescence, uniform flow High Verlaan (2001), Grevelink (2007)
Inlet cyclone 90-99% Best coalescence, centrifugal Very High Hoffmann and Stein (2008)
Schoepentoeter 80-90% Good momentum absorption Very High Grevelink (2007)

References:

  • Arnold, K., Stewart, M. (2008), Surface Production Operations, Vol. 1, 3rd ed., Gulf Professional Publishing.
  • Verlaan, C.C.J. (2001), "Performance of novel mist eliminators", PhD Thesis, Delft University of Technology.
  • Grevelink, J.G.H. (2007), "Inlet devices for separation equipment", Shell Global Solutions (public conference paper).
  • Hoffmann, A.C., Stein, L.E. (2008), Gas Cyclones and Swirl Tubes, 2nd ed., Springer.
  • Bothamley, M. (2013), "Gas/Liquid Separators: Quantifying Separation Performance", Oil and Gas Facilities, SPE 0813-0034-OGF (Part 1-3).
Version:
1.0
Author:
NeqSim team
See Also:

  • Field Details

    • serialVersionUID

      private static final long serialVersionUID
      Serialization version UID.
      See Also:

    • deviceType

      private InletDeviceModel.InletDeviceType deviceType

    • inletNozzleDiameter

      private double inletNozzleDiameter

    • inletMomentum

      private double inletMomentum

    • overrideBulkEfficiency

      private double overrideBulkEfficiency

    • overrideDsdMultiplier

      private double overrideDsdMultiplier

    • bulkSeparationEfficiency

      private double bulkSeparationEfficiency

    • pressureDrop

      private double pressureDrop

    • nozzleVelocity

      private double nozzleVelocity

    • momentumFlux

      private double momentumFlux

    • downstreamDSD

      private DropletSizeDistribution downstreamDSD

  • Constructor Details

    • InletDeviceModel

      public InletDeviceModel()
      Creates a new InletDeviceModel with no device (pipe entry).

    • InletDeviceModel

      public InletDeviceModel(InletDeviceModel.InletDeviceType deviceType)
      Creates a new InletDeviceModel for the specified device type.
      Parameters:
      deviceType - the inlet device type

  • Method Details

    • calculate

      public void calculate(DropletSizeDistribution incomingDSD, double gasDensity, double liquidDensity, double gasVolumeFlow, double liquidVolumeFlow, double surfaceTension)
      Calculates the inlet device performance for the given flow conditions.

      The inlet device:

      1. Computes the nozzle velocity and momentum flux from the inlet pipe flow.
      2. Determines bulk liquid separation efficiency based on device type and momentum.
      3. Transforms the incoming DSD based on the device's coalescence/re-atomization behaviour.
      4. Calculates pressure drop across the device.
      Parameters:
      incomingDSD - droplet size distribution from inlet pipe flow
      gasDensity - gas density [kg/m3]
      liquidDensity - liquid density [kg/m3]
      gasVolumeFlow - gas volume flow rate [m3/s] at actual conditions
      liquidVolumeFlow - liquid volume flow rate [m3/s] at actual conditions
      surfaceTension - gas-liquid surface tension [N/m]

    • calcBulkEfficiency

      private double calcBulkEfficiency(double momentum)
      Calculates the bulk liquid separation efficiency of the inlet device.

      The bulk efficiency depends on:

      • Device type (inherent design efficiency)
      • Momentum flux at the nozzle (too high = re-entrainment, too low = poor separation)

      Most inlet devices have an optimal momentum range. The Bothamley (2013) recommended momentum ranges are:

      • Deflector plate: < 1500 Pa (rho*v^2)
      • Half-pipe: < 3500 Pa
      • Inlet vane: < 6000 Pa
      • Inlet cyclone: < 15000 Pa
      • Schoepentoeter: < 9000 Pa
      Parameters:
      momentum - nozzle momentum flux [Pa]
      Returns:
      bulk efficiency [0-1]

    • transformDSD

      private DropletSizeDistribution transformDSD(DropletSizeDistribution incomingDSD, double surfaceTension)
      Transforms the incoming DSD through the inlet device.

      The effect depends on device type:

      • No device: passes DSD unchanged.
      • Deflector/Half-pipe: removes largest droplets, moderate increase in d_50 through coalescence on the wall and redistribution.
      • Inlet vane: removes bulk liquid, coalesces small droplets, shifts DSD coarser (beneficial for downstream gravity).
      • Inlet cyclone: centrifugal separation, very effective at removing fine drops, significantly reduces DSD downstream.
      • Schoepentoeter: absorbs momentum, moderate coalescence, prevents re-entrainment from liquid surface.
      Parameters:
      incomingDSD - upstream DSD from pipe flow
      surfaceTension - used for re-atomization estimate [N/m]
      Returns:
      transformed downstream DSD

    • toJson

      public String toJson()
      Returns a JSON representation of the inlet device calculation results.
      Returns:
      JSON string

    • getDeviceType

      public InletDeviceModel.InletDeviceType getDeviceType()
      Gets the inlet device type.
      Returns:
      device type

    • setDeviceType

      public void setDeviceType(InletDeviceModel.InletDeviceType deviceType)
      Sets the inlet device type.
      Parameters:
      deviceType - the device type

    • getInletNozzleDiameter

      public double getInletNozzleDiameter()
      Gets the inlet nozzle diameter.
      Returns:
      nozzle diameter [m]

    • setInletNozzleDiameter

      public void setInletNozzleDiameter(double diameter)
      Sets the inlet nozzle diameter.
      Parameters:
      diameter - nozzle diameter [m]

    • getBulkSeparationEfficiency

      public double getBulkSeparationEfficiency()
      Gets the calculated bulk separation efficiency.
      Returns:
      bulk efficiency [0-1]

    • getPressureDrop

      public double getPressureDrop()
      Gets the calculated pressure drop across the inlet device.
      Returns:
      pressure drop [Pa]

    • getNozzleVelocity

      public double getNozzleVelocity()
      Gets the nozzle velocity at the inlet.
      Returns:
      nozzle velocity [m/s]

    • getMomentumFlux

      public double getMomentumFlux()
      Gets the nozzle momentum flux.
      Returns:
      momentum flux [Pa] (rho_mix * v^2)

    • getDownstreamDSD

      public DropletSizeDistribution getDownstreamDSD()
      Gets the downstream DSD after the inlet device.
      Returns:
      transformed DSD, or null if not calculated

    • setOverrideBulkEfficiency

      public void setOverrideBulkEfficiency(double efficiency)
      Overrides the default bulk separation efficiency for this device.
      Parameters:
      efficiency - custom bulk efficiency [0-1], set to 0 to use device type default

    • setOverrideDsdMultiplier

      public void setOverrideDsdMultiplier(double multiplier)
      Overrides the default DSD transformation multiplier.
      Parameters:
      multiplier - custom multiplier, set to 0 to use device type default