Møtran^® Features

• Formulation:
  • Full two-fluid model—6 equations (mass, momentum, energy for each phase)
  • Arbitrary networks of one-dimensional components
  • Transient or steady-state
  • Open- or closed-loop systems

• Two-Phase Models:
  • Full flow regime maps
    • valid at all inclinations and gravity levels
    • one-phase gas, bubbly, slug, stratified, annular, one-phase liquid regimes
    • mechanistic transition levels
  • One-component (e.g., steam-water) and two-component (air-water)
  • Mechanistic wall and interfacial shear models—regime-based
  • Wall heat transfer regime map and models
    • forced convection boiling
    • condensation (bubbly, slug, stratified, annular)
    • single-phase and homogenous forced convection
  • Interfacial heat transfer models based on interfacial area
  • Component models for pumps, tees, accumulators, and valves
  • Provision for user-programmed models

• Boundary Conditions:
  • Fixed inflow, outflow
  • Steady or time-varying wall heat flux, wall temperature, valve opening
  • Steady or time-varying gravity

• Fluid Properties:
  • Variable or constant properties
  • DIPPR format property database
  • User-defined fluids supported

• Graphical User Interface:
  • Drag-and-drop system layout

  Components		Instruments
  Pipe		Temperature
  Evaporator		Pressure
  Condenser		Velocity
  Tee		Flow Rate
  Pump		Flow Regime
  Valve		Void Fraction
  Accumulator		Quality

  • Subsystem grouping—store/retrieve from library
  • Real-time plotting of solution convergence
  • Multichannel plotting of transient data
  • Printing of graphic windows
  • Data export for spreadsheets or other analysis and plotting programs

• Calculation Controls:
  • Variable time steps and intervals
  • Restart from previous run
  • Default solution control parameters included with full access for adjustment