modelFlow1D_check
Extended Flow1D model with mass & energy balance computation
Extends from Water.Flow1D (1-dimensional fluid flow model for water/steam (finite volumes)).
Information
This model extends Water.Flow1D by adding the computation of mass and energy flows and buildups. It can be used to check the correctness of the Water.Flow1D model.
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Real | pi (from Flow1DBase) | Modelica.Constants.pi | |
| Integer | N (from Flow1DBase) | 2 | Number of nodes for thermal variables |
| Integer | Nw (from Flow1DBase) | N - 1 | Number of volumes on the wall interface |
| Integer | Nt (from Flow1DBase) | 1 | Number of tubes in parallel |
| SI.Distance | L (from Flow1DBase) | Tube length | |
| SI.Position | H (from Flow1DBase) | 0 | Elevation of outlet over inlet |
| SI.Area | A (from Flow1DBase) | Cross-sectional area (single tube) | |
| SI.Length | omega (from Flow1DBase) | Perimeter of heat transfer surface (single tube) | |
| SI.Length | Dhyd (from Flow1DBase) | omega/pi | Hydraulic Diameter (single tube) |
| Medium.MassFlowRate | wnom (from Flow1DBase) | Nominal mass flowrate (total) | |
| ThermoPower.Choices.Flow1D.FFtypes | FFtype (from Flow1DBase) | ThermoPower.Choices.Flow1D.FFtypes.NoFriction | Friction Factor Type |
| SI.PressureDifference | dpnom (from Flow1DBase) | 0 | Nominal pressure drop (friction term only!) |
| Real | Kfnom (from Flow1DBase) | 0 | Nominal hydraulic resistance coefficient (DP = Kfnom*w^2/rho) |
| Medium.Density | rhonom (from Flow1DBase) | 0 | Nominal inlet density |
| SI.PerUnit | Cfnom (from Flow1DBase) | 0 | Nominal Fanning friction factor |
| SI.PerUnit | e (from Flow1DBase) | 0 | Relative roughness (ratio roughness/diameter) |
| SI.PerUnit | Kfc (from Flow1DBase) | 1 | Friction factor correction coefficient |
| Boolean | DynamicMomentum (from Flow1DBase) | false | Inertial phenomena accounted for |
| ThermoPower.Choices.Flow1D.HCtypes | HydraulicCapacitance (from Flow1DBase) | ThermoPower.Choices.Flow1D.HCtypes.Downstream | Location of the hydraulic capacitance |
| Boolean | avoidInletEnthalpyDerivative (from Flow1DBase) | true | Avoid inlet enthalpy derivative |
| Boolean | allowFlowReversal (from Flow1DBase) | system.allowFlowReversal | = true to allow flow reversal, false restricts to design direction |
| SI.PerUnit | wnf (from Flow1DBase) | 0.02 | Fraction of nominal flow rate at which linear friction equals turbulent friction |
| SI.Acceleration | g (from Flow1DBase) | Modelica.Constants.g_n | |
| SI.PerUnit | dzdx (from Flow1DBase) | H/L | Slope |
| SI.Length | l (from Flow1DBase) | L/(N - 1) | Length of a single volume |
| SI.Volume | V (from Flow1DBase) | Nt*A*L | Total volume (all Nt tubes) |
| Initialisation | |||
| Choices.FluidPhase.FluidPhases | FluidPhaseStart (from Flow1DBase) | Choices.FluidPhase.FluidPhases.Liquid | Fluid phase (only for initialization!) |
| Medium.AbsolutePressure | pstart (from Flow1DBase) | 1e5 | Pressure start value |
| Medium.SpecificEnthalpy | hstartin (from Flow1DBase) | if FluidPhaseStart == Choices.FluidPhase.FluidPhases.Liquid then 1e5 else if FluidPhaseStart == Choices.FluidPhase.FluidPhases.Steam then 3e6 else 1e6 | Inlet enthalpy start value |
| Medium.SpecificEnthalpy | hstartout (from Flow1DBase) | if FluidPhaseStart == Choices.FluidPhase.FluidPhases.Liquid then 1e5 else if FluidPhaseStart == Choices.FluidPhase.FluidPhases.Steam then 3e6 else 1e6 | Outlet enthalpy start value |
| Medium.SpecificEnthalpy[N] | hstart (from Flow1DBase) | linspace(hstartin, hstartout, N) | Start value of enthalpy vector (initialized by default) |
| Choices.Init.Options | initOpt (from Flow1DBase) | system.initOpt | Initialisation option |
| Boolean | noInitialPressure (from Flow1DBase) | false | Remove initial equation on pressure |
Connectors
| Type | Name | Default | Description |
|---|---|---|---|
| FlangeA | infl (from Flow1DBase) | ||
| FlangeB | outfl (from Flow1DBase) | ||
| ThermoPower.Thermal.DHT | wall (from Flow1D) |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| ThermoPower.System | system (from Flow1DBase) | System wide properties | |
| SI.Power | Q (from Flow1DBase) | Total heat flow through the lateral boundary (all Nt tubes) | |
| SI.Time | Tr (from Flow1DBase) | Residence time | |
| Medium.ThermodynamicState[N] | fluidState (from Flow1D) | Thermodynamic state of the fluid at the nodes | |
| SI.Length | omega_hyd (from Flow1D) | Wet perimeter (single tube) | |
| SI.Pressure | Dpfric (from Flow1D) | Pressure drop due to friction (total) | |
| SI.Pressure | Dpfric1 (from Flow1D) | Pressure drop due to friction (from inlet to capacitance) | |
| SI.Pressure | Dpfric2 (from Flow1D) | Pressure drop due to friction (from capacitance to outlet) | |
| SI.Pressure | Dpstat (from Flow1D) | Pressure drop due to static head | |
| SI.MassFlowRate | win (from Flow1D) | Flow rate at the inlet (single tube) | |
| SI.MassFlowRate | wout (from Flow1D) | Flow rate at the outlet (single tube) | |
| Real | Kf (from Flow1D) | Hydraulic friction coefficient | |
| Real | dwdt (from Flow1D) | Dynamic momentum term | |
| Real | Cf (from Flow1D) | Fanning friction factor | |
| Medium.AbsolutePressure | p (from Flow1D) | Fluid pressure for property calculations | |
| SI.MassFlowRate | w (from Flow1D) | Mass flowrate (single tube) | |
| SI.MassFlowRate[N - 1] | wbar (from Flow1D) | ||
| SI.Velocity[N] | u (from Flow1D) | Fluid velocity | |
| Medium.Temperature[N] | T (from Flow1D) | Fluid temperature | |
| Medium.SpecificEnthalpy[N] | h (from Flow1D) | Fluid specific enthalpy at the nodes | |
| Medium.SpecificEnthalpy[N - 1] | htilde (from Flow1D) | Enthalpy state variables | |
| Medium.Density[N] | rho (from Flow1D) | Fluid nodal density | |
| SI.Mass | M (from Flow1D) | Fluid mass | |
| Real[N - 1] | dMdt (from Flow1D) | Time derivative of mass in each cell between two nodes | |
| SI.SpecificEnergy | Etot | ||
| SI.SpecificEnergy[N - 1] | Evol | ||
| SI.Mass | Mtot | ||
| SI.Mass[N - 1] | Mvol | ||
| SI.MassFlowRate | balM | ||
| SI.Power | balE |
Revisions
- 1 Oct 2003
by Francesco
Casella:
First release.