Line Entrance $—$ Entrance element of a long line

The LineEntrance component contains the equations for the entrance element (that is, the beginning of a long line). The connector port_A is used to connect the long line to another hydraulic component.

Connections

 Name Description Modelica ID $\mathrm{oil}$ oil ${\mathrm{port}}_{A}$ Port A, where oil flows into the component ($0, ${p}_{B}<{p}_{A}$ means $0<\mathrm{Δp}$) port_A ${\mathrm{port}}_{B}$ Port A, where oil leaves the component ($q<0$, ${p}_{B}<{p}_{A}$ means $0<\mathrm{Δp}$) port_B

Parameters

General Parameters

 Name Default Units Description Modelica ID steady-state init $\mathrm{false}$ If true, initialize in steady state steadyStateInit constant properties $\mathrm{true}$ If true, properties are treated as constant over time constantProperties elastic wall $\mathrm{false}$ If true, pipe properties affect speed of sound in oil elasticWall dynamic friction $\mathrm{false}$ If true, dynamic friction dynFriction ${\ell }_{\mathrm{element}}$ $m$ Length of one element ElementLength $d$ $m$ Line diameter diameter $\mathrm{Δh}$ $0$ $m$ Height difference heightDiff friction type [1] Type of flow model frictionType ${K}_{\mathrm{pipe}}$ Pipe bulk modulus of elasticity bulkModPipe roughness $0$ $m$ Roughness of pipe roughness ${\mathrm{\rho }}_{0}$ $\frac{\mathrm{kg}}{{m}^{3}}$ Constant density, if constantProperties is true rho0 ${\mathrm{\nu }}_{0}$ $\frac{{m}^{2}}{s}$ Constant viscosity, if constantProperties is true nu0 ${\mathrm{\beta }}_{0}$ $\mathrm{Pa}$ Bulk Modulus beta0 ${\mathrm{ΔT}}_{\mathrm{system}}$ $0$ $K$ Temperature offset from system temperature dT_system

[1] $\mathrm{Hydraulics.Lines.FrictionTypes.Laminar}$

Constant Parameters

 Name Default Units Description Modelica ID ${\mathrm{\Delta }}_{\mathrm{rel}}$ $\frac{\mathrm{roughness}}{d}$ Relative roughness Delta

Constants

 Name Value Units Description Modelica ID ${k}_{1}$ $0.192$ k1 ${k}_{2}$ $0.0948$ k2 ${k}_{3}$ $0.0407$ k3 ${\mathrm{\tau }}_{1}$ $0.25$ tau1 ${\mathrm{\tau }}_{2}$ $0.0352$ tau2 ${\mathrm{\tau }}_{3}$ $0.0024$ tau3