 Check Valve 2 - MapleSim Help

Check Valve 2

Check valve with continuous variable  Description

The Check Valve 2 (or Check Valve II) component allows fluid flow in one direction, from port A to port B.

This model uses a continuous-variable to model the change from open to closed. In the open-state the valve has a resistance given by ${R}_{\mathrm{open}}$. In the closed-state the valve has a conductance given by ${G}_{\mathrm{close}}$. Optional Volumes The boolean parameters Use volume A and Use volume B, when true, add optional volumes ${V}_{A}$  and ${V}_{B}$ to ports A and B, respectively. See Port Volumes for details. If two orifices or valves are connected, enabling a volume at the common port reduces the stiffness of the system and improves the solvability. Equations $\mathrm{closed}=\left(s<0\right)$ $p={p}_{A}-{p}_{B}=\left\{\begin{array}{cc}\frac{s}{{G}_{\mathrm{closed}}}& \mathrm{closed}\\ s& \mathrm{otherwise}\end{array}\phantom{\rule[-0.0ex]{5.0ex}{0.0ex}}q={q}_{A}-{q}_{\mathrm{VA}}=\left\{\begin{array}{cc}s& \mathrm{closed}\\ \frac{s}{{R}_{\mathrm{open}}}& \mathrm{otherwise}\end{array}$ ${V}_{{f}_{A}}=\left\{\begin{array}{cc}{V}_{A}\left(1+\frac{{p}_{A}}{\mathrm{El}}\right)& \mathrm{useVolumeA}\\ 0& \mathrm{otherwise}\end{array}\phantom{\rule[-0.0ex]{4.0ex}{0.0ex}}{V}_{{f}_{B}}=\left\{\begin{array}{cc}{V}_{B}\left(1+\frac{{p}_{B}}{\mathrm{El}}\right)& \mathrm{useVolumeB}\\ 0& \mathrm{otherwise}\end{array}$ ${q}_{{V}_{A}}=\left\{\begin{array}{cc}\frac{\mathrm{d}{V}_{{f}_{A}}}{\mathrm{d}t}& \mathrm{useVolumeA}\\ 0& \mathrm{otherwise}\end{array}\phantom{\rule[-0.0ex]{5.5ex}{0.0ex}}{q}_{{V}_{B}}=\left\{\begin{array}{cc}\frac{\mathrm{d}{V}_{{f}_{B}}}{\mathrm{d}t}& \mathrm{useVolumeB}\\ 0& \mathrm{otherwise}\end{array}$ ${q}_{A}+{q}_{B}-{q}_{\mathrm{VA}}-{q}_{\mathrm{VB}}=0$ ${q}_{\mathrm{summary}}=q\mathrm{flowScaleSummary}\phantom{\rule[-0.0ex]{7.5ex}{0.0ex}}{\mathrm{dp}}_{\mathrm{summary}}=p\mathrm{pressScaleSummary}$ Variables

 Name Units Description Modelica ID $p$ $\mathrm{Pa}$ Pressure drop from A to B p $q$ $\frac{{m}^{3}}{s}$ Flow rate from port A to port B q ${q}_{\mathrm{summary}}$ $\frac{{m}^{3}}{s}$ Internal flow sensor q_summary ${\mathrm{dp}}_{\mathrm{summary}}$ $\mathrm{Pa}$ Internal pressure difference sensor dp_summary ${V}_{{f}_{x}}$ ${m}^{3}$ Effective volume at port $x,x\in \left\{A,B\right\}$ Vfx ${q}_{{V}_{x}}$ $\frac{{m}^{3}}{s}$ Flow rate into effective volume at port $x,x\in \left\{A,B\right\}$ qVx Connections

 Name Description Modelica ID $\mathrm{portA}$ Upstream hydraulic port portA $\mathrm{portB}$ Downstream hydraulic port portB Parameters General Parameters

 Name Default Units Description Modelica ID ${R}_{\mathrm{open}}$ $1·{10}^{-5}$ $\frac{\mathrm{Pa}s}{{m}^{3}}$ Open check valve resistance Ropen ${G}_{\mathrm{closed}}$ $1·{10}^{-5}$ $\frac{{m}^{3}}{\mathrm{Pa}s}$ Closed check valve conductance Gclosed Start closed $\mathrm{true}$ True initializes valve to closed, false to open Startclosed Optional Volumes

 Name Default Units Description Modelica ID $\mathrm{useVolumeA}$ $\mathrm{false}$ True (checked) means a hydraulic volume chamber is added to portA useVolumeA ${V}_{A}$ $1·{10}^{-6}$ ${m}^{3}$ Volume of chamber A Va $\mathrm{useVolumeB}$ $\mathrm{false}$ True (checked) means a hydraulic volume chamber is added to portB useVolumeB ${V}_{B}$ $1·{10}^{-6}$ ${m}^{3}$ Volume of chamber B Vb Name Units Description Modelica ID $\mathrm{\nu }$ $\frac{{m}^{2}}{s}$ Kinematic viscosity of fluid nu $\mathrm{\rho }$ $\frac{\mathrm{kg}}{{m}^{3}}$ Density of fluid rho $\mathrm{El}$ $\mathrm{Pa}$ Bulk modulus of fluid El