modelPipePhysical
Information
The model contains the physical definition of the pipe. Depending on the parameter values, between 0 and 3 equations are missing, related to the sectional shape and length of the pipe.
If you make the parameter isCircular=true, the Perimeter will be calculated from Di and, as there is inside the model an equation relating Di, Perimeter, and Section, just 1 equation related with the sectional shape will be missing. If you make the parameter useDiameter=true, it will be taken from the parameter di, and the sectional description will be completed. Otherwise Di or Section must be supplied.
As an alternative to isCircular=true, you can make the parameter useSectionAndPerimeter=true. In this case Section and Perimeter will be taken from their values in parameters. If none of the previous alternatives has been used, it is necessary to supply equations to solve two of the following variables: Di, Section, Perimeter.
Regarding the pipe length, is you make the parameter useTubeLength=true. The tube length will be taken from the parameter lTube. Otherwise an equation to solve for the pipe length must be supplied,
The pipe allows for the use of multiple parallel paths, specified by the parameter numTubes.
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Physical data | |||
| Boolean | useTubeLength | true | use the supplied length |
| Modelica.Units.SI.Distance | lTube | 0 | supplied individual tube length |
| Boolean | fixNumTubes | true | if true fixes the number of tubes to numTubes |
| Integer | numTubes | 1 | number of parallel identical paths |
| Boolean | isCircular | true | the pipe is circular in shape |
| Boolean | useDiameter | true | the supplied diameter will be used for calculation of section and perimeter |
| Modelica.Units.SI.Distance | di | 0.0 | supplied internal diameter if path is circular |
| Boolean | useSectionAndPerimeter | false | the supplied section and perimeter will be used |
| Modelica.Units.SI.Area | section | 0 | supplied pipe section if not circular |
| Modelica.Units.SI.Distance | perimeter | 0 | supplied perimeter if not circular |
| Modelica.Units.SI.Distance | thickness | 1e-3 | pipe thickness. Vessel wall thickness for halfcoils |
| Modelica.Units.SI.Distance | roughness | 1.5e-005 | pipe roughness. SS:1.5e-5, Steel new:4.6e-5, Steel old:2.0e-4, Concrete:1.5e-3 |
| Modelica.Units.SI.Distance | thicknessInsul | 0 | insulation thickness |
| Modelica.Units.SI.Density | rhoWall | 8000 | |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.Units.SI.Diameter | Di | pipe internal diameter only if circular, otherwise four times Section/Perimeter | |
| Modelica.Units.SI.Area | PathSection | Internal section of the tube. But not the flow section if double pipe | |
| Modelica.Units.SI.Distance | PathPerimeter | Internal perimeter of the tube. But not the flow perimeter if double pipe | |
| Modelica.Units.SI.Distance | Ltotal | total pipe length, as necessary for obtainning its total weight | |
| Modelica.Units.SI.Distance | Ltube | pipe path length, as necessary for obtainning friction loss | |
| Integer | NumTubes | number of parallel identical paths | |
| Modelica.Units.SI.Area | SiTube | each tube internal surface | |
| Modelica.Units.SI.Area | SiTotal | total pipe internal surface | |
| Modelica.Units.SI.Volume | ViTube | each tube internal volume | |
| Modelica.Units.SI.Volume | ViTotal | total pipe internal volume | |
| Modelica.Units.SI.Diameter | Do | pipe external diameter | |
| Modelica.Units.SI.Diameter | Dinsul | pipe diameter with insulation | |
| Modelica.Units.SI.Area | SoTube | each tube external surface | |
| Modelica.Units.SI.Area | SoTotal | total pipe external surface | |
| Modelica.Units.SI.Volume | VoTube | each tube external volume | |
| Modelica.Units.SI.Volume | VoTotal | total pipe external volume | |
| Modelica.Units.SI.Area | SinsulTube | each tube insulation surface | |
| Modelica.Units.SI.Area | SinsulTotal | total pipe insulation surface | |
| Modelica.Units.SI.Mass | MassPipeTotal | total mass of the pipe |