WOLFRAM SYSTEM MODELER
VesselPortsDataData to describe inlet/outlet ports at vessels: diameter -- Inner (hydraulic) diameter of inlet/outlet port height -- Height over the bottom of the vessel zeta_out -- Hydraulic resistance out of vessel, default 0.5 for small diameter mounted flush with the wall zeta_in -- Hydraulic resistance into vessel, default 1.04 for small diameter mounted flush with the wall |
 |
Wolfram Language
In[1]:=
SystemModel["Modelica.Fluid.Vessels.BaseClasses.VesselPortsData"]
Out[1]:=
Information
This information is part of the Modelica Standard Library maintained by the Modelica Association.
Vessel Port Data
This record describes the ports of a vessel. The variables in it are mostly self-explanatory (see list below); only the ζ loss factors are discussed further. All data is quoted from Idelchik (1994).
Outlet Coefficients
If a straight pipe with constant cross section is mounted flush with the wall, its outlet pressure loss coefficient will be ζ = 0.5 (Idelchik, p. 160, Diagram 3-1, paragraph 2).
If a straight pipe with constant cross section is mounted into a vessel such that the entrance into it is at a distance b from the wall (inside) the following table can be used. Herein, δ is the tube wall thickness (Idelchik, p. 160, Diagram 3-1, paragraph 1).
| b / D_hyd | ||||||
|---|---|---|---|---|---|---|
| 0.000 | 0.005 | 0.020 | 0.100 | 0.500-∞ | ||
| δ / D_hyd | 0.000 | 0.50 | 0.63 | 0.73 | 0.86 | 1.00 |
| 0.008 | 0.50 | 0.55 | 0.62 | 0.74 | 0.88 | |
| 0.016 | 0.50 | 0.51 | 0.55 | 0.64 | 0.77 | |
| 0.024 | 0.50 | 0.50 | 0.52 | 0.58 | 0.68 | |
| 0.040 | 0.50 | 0.50 | 0.51 | 0.51 | 0.54 | |
If a straight pipe with a circular bellmouth inlet (collector) without baffle is mounted flush with the wall then its pressure loss coefficient can be established from the following table. Herein, r is the radius of the bellmouth inlet surface (Idelchik, p. 164 f., Diagram 3-4, paragraph b)
| r / D_hyd | ||||||
|---|---|---|---|---|---|---|
| 0.01 | 0.03 | 0.05 | 0.08 | 0.16 | ≥0.20 | |
| ζ | 0.44 | 0.31 | 0.22 | 0.15 | 0.06 | 0.03 |
If a straight pipe with a circular bellmouth inlet (collector) without baffle is mounted at a distance from a wall then its pressure loss coefficient can be established from the following table. Herein, r is the radius of the bellmouth inlet surface (Idelchik, p. 164 f., Diagram 3-4, paragraph a)
| r / D_hyd | ||||||
|---|---|---|---|---|---|---|
| 0.01 | 0.03 | 0.05 | 0.08 | 0.16 | ≥0.20 | |
| ζ | 0.87 | 0.61 | 0.40 | 0.20 | 0.06 | 0.03 |
Inlet Coefficients
If a straight pipe with constant circular cross section is mounted flush with the wall, its vessel inlet pressure loss coefficient will be according to the following table (Idelchik, p. 209 f., Diagram 4-2 with A_port/A_vessel = 0 and Idelchik, p. 640, Diagram 11-1, graph a). According to the text, m = 9 is appropriate for fully developed turbulent flow.
| m | ||||||
|---|---|---|---|---|---|---|
| 1.0 | 2.0 | 3.0 | 4.0 | 7.0 | 9.0 | |
| ζ | 2.70 | 1.50 | 1.25 | 1.15 | 1.06 | 1.04 |
For larger port diameters, relative to the area of the vessel, the inlet pressure loss coefficient will be according to the following table (Idelchik, p. 209 f., Diagram 4-2 with m = 7).
| A_port / A_vessel | ||||||
|---|---|---|---|---|---|---|
| 0.0 | 0.1 | 0.2 | 0.4 | 0.6 | 0.8 | |
| ζ | 1.04 | 0.84 | 0.67 | 0.39 | 0.18 | 0.06 |
References
- Idelchik I.E. (1994):
- Handbook of Hydraulic Resistance. 3rd edition, Begell House, ISBN 0-8493-9908-4
Parameters (4)
| diameter |
Value: Type: Diameter (m) Description: Inner (hydraulic) diameter of inlet/outlet port |
|---|---|
| height |
Value: 0 Type: Height (m) Description: Height over the bottom of the vessel |
| zeta_out |
Value: 0.5 Type: Real Description: Hydraulic resistance out of vessel, default 0.5 for small diameter mounted flush with the wall |
| zeta_in |
Value: 1.04 Type: Real Description: Hydraulic resistance into vessel, default 1.04 for small diameter mounted flush with the wall |
Used in Components (2)
 |
Modelica.Fluid.Examples.AST_BatchPlant.BaseClasses Tank with inlet/outlet ports and with inlet ports at the top |
 |
Modelica.Fluid.Vessels.BaseClasses Lumped volume with a vector of fluid ports and replaceable heat transfer model |