.ThermoCycle.Components.FluidFlow.Pipes.Flow1Dim_MD

1-D fluid flow model (finite volume discretization - real fluid model) based on the exact integration of the mean volume density

Information

Model Flow1Dim_2ph describes the flow of fluid through a discretized one dimentional tube.

Enthalpy and pressure are selected as state variable

In the model the node variables are characterized by the following syntax: _node.

The model is discretized using the collocated grid method: the nodes variable are the state variables and the cell variable are deduced

.

UpWind discretization is considered i.e. h_node[j+1] = h_node[j].

Numerical options

In this tab several options are available to make the model more robust:

  • Mdotconst: assume constant mass flow rate at each node.
  • max_der: if true the density derivative is truncated during phase change
  • filter_dMdt: if true a first order filter is applied to the fast variations of the density with respect to time
  • max_drhodt: it represents the maximum value of the density derivative. It activates when using max_der is set to true
  • TT: it represents the integration time of the first order filter. It activates when filter_dMdt is set to true

The model is characterized by a SummaryClass that provide a quick access to the following variables once the model is simulated:

  • Temperature at the center of each cell
  • Temperature at each node
  • Enthalpy at each node
  • Enthalpy at the center of each cell
  • Density at the center of each cell
  • Massflow at each nodes
  • Vapor quality at each nodes
  • Pressure in the tube

The model is based on:

Casella, F. Object-oriented modelling of two-phase fluid flows by the finite volume method. Proceedings 5th Mathmod Vienna, Austria, Sep 2006, p. 68.

Contents

NameDescription
 Medium
 SummaryClass
Generated at 2025-04-25T18:20:13Z by OpenModelicaOpenModelica 1.25.0 using GenerateDoc.mos