Template: RotationalComponentTorque - MapleSim Help

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Template: RotationalComponentTorque

The RotationalComponentTorque template is a partial model of a two-port hydraulic component with two rotational flanges connected by a shaft. The hydraulic ports are A and B, the flanges are flange_a and flange_b.

Variables

 Name Value Units Description Modelica ID ${p}_{A}$ $\mathrm{Pa}$ pressure at port A port_A.p ${p}_{B}$ $\mathrm{Pa}$ pressure at port B port_B.p ${p}_{\mathrm{A\left(abs\right)}}$ ${p}_{A}+{p}_{\mathrm{oil\left(atm\right)}}$ $\mathrm{Pa}$ absolute pressure at port A pA_abs ${p}_{\mathrm{B\left(abs\right)}}$ ${p}_{B}+{p}_{\mathrm{oil\left(atm\right)}}$ $\mathrm{Pa}$ absolute pressure at port B pB_abs ${p}_{\mathrm{A\left(lim\right)}}$ $\mathrm{max}\left({p}_{A},{p}_{\mathrm{oil\left(vapour\right)}}-{p}_{\mathrm{oil\left(atm\right)}}\right)$ $\mathrm{Pa}$ limited gauge pressure at port A pA_limited ${p}_{\mathrm{B\left(lim\right)}}$ $\mathrm{max}\left({p}_{B},{p}_{\mathrm{oil\left(vapour\right)}}-{p}_{\mathrm{oil\left(atm\right)}}\right)$ $\mathrm{Pa}$ limited gauge pressure at port B pB_limited ${p}_{\mathrm{A\left(sum\right)}}$ ${p}_{A}$ $\mathrm{Pa}$ pressure at port A summary_pA ${p}_{\mathrm{B\left(sum\right)}}$ ${p}_{B}$ $\mathrm{Pa}$ pressure at port B summary_pB $\mathrm{Δp}$ ${p}_{\mathrm{A\left(lim\right)}}-{p}_{\mathrm{B\left(lim\right)}}$ $\mathrm{Pa}$ pressure differential dp ${p}_{\mathrm{sat}}$ $\mathrm{oil.gasSaturationPressure}\left(T,\mathrm{oil.v_gas}\right)$ $\mathrm{Pa}$ gas saturation pressure p_sat ${m}_{\mathrm{flow\left(A\right)}}$ $\frac{\mathrm{kg}}{s}$ mass flow rate at port A; positive if oil is entering the component. port_A.m_flow ${m}_{\mathrm{flow\left(B\right)}}$ $-{m}_{\mathrm{flow\left(A\right)}}$ $\frac{\mathrm{kg}}{s}$ mass flow rate at port B; positive if oil is entering the component. port_B.m_flow ${\mathrm{HP}}_{\mathrm{sum}}$ $-\mathrm{Δp}q$ $W$ hydraulic power summary_HP ${\mathrm{MP}}_{\mathrm{sum}}$ ${\mathrm{\tau }}_{a}{\stackrel{·}{\phi }}_{a}+{\mathrm{\tau }}_{b}{\stackrel{·}{\phi }}_{b}$ $W$ rotational power summary_MP $q$ $\frac{{m}_{\mathrm{flow\left(A\right)}}}{\mathrm{\rho }}$ $\frac{{m}^{3}}{s}$ volume flow rate into port A q ${q}_{\mathrm{sum}}$ $q$ $\frac{{m}^{3}}{s}$ volume flow rate into port A summary_q $\mathrm{\rho }$ $\mathrm{\rho }\left(\mathrm{Δp},{p}_{\mathrm{A\left(abs\right)}},{p}_{\mathrm{B\left(abs\right)}},T,\mathrm{oil}\right)$ $\frac{\mathrm{kg}}{{m}^{3}}$ upstream density of oil rho $\mathrm{\nu }$ $\mathrm{\nu }\left(\mathrm{Δp},{p}_{\mathrm{A\left(abs\right)}},{p}_{\mathrm{B\left(abs\right)}},T,\mathrm{oil}\right)$ $\frac{{m}^{2}}{s}$ upstream kinematic viscosity of oil nu $T$ ${T}_{\mathrm{oil\left(0\right)}}+{\mathrm{ΔT}}_{\mathrm{system}}$ $K$ local temperature of oil T $\mathrm{\tau }$ $Nm$ sum of torques at flanges tau $w$ ${\stackrel{·}{\phi }}_{a}$ $\frac{\mathrm{rad}}{s}$ angular velocity of pump shaft w ${\mathrm{\phi }}_{a}$ $\mathrm{rad}$ angular position of flange a flange_a.phi ${\mathrm{\phi }}_{b}$ ${\mathrm{\phi }}_{a}$ $\mathrm{rad}$ angular position of flange b flange_b.phi

Parameters

 Name Default Units Description Modelica ID ${\mathrm{ΔT}}_{\mathrm{system}}$ 0 $K$ temperature offset from system temperature dT_system use volume A true true means a volume is present at port A useVolumeA use volume B true true means a volume is present at port B useVolumeB ${V}_{A}$ ${10}^{-6}$ ${m}^{3}$ volume at port A volumeA ${V}_{B}$ ${10}^{-6}$ ${m}^{3}$ volume at port B volumeB

 Assumptions No storage of energy or mass.
 Sign Conventions If the pressure at port A is greater than the pressure at port B, the volume flow rate at port A is positive.

Examples

Extend the RotationalComponentTorque template to create a simple pump with constant displacement.

Assign the equations that relate the hydraulic variables, $\mathrm{Δp}$ and $q$, to the rotational variables, $w$, $\mathrm{\tau }$.

 > $\mathrm{eqs}≔\left\{q=\frac{\mathrm{Dpump}w}{\mathrm{π}},-\frac{\mathrm{Dpump}\mathrm{dp}}{\mathrm{π}}=\mathrm{τ}\right\}:$

Create the modelica for a SimplePump model that extends the template.

 > $\mathrm{MapleSim}:-\mathrm{Tools}:-\mathrm{MapleToModelica}\left(\mathrm{eqs},'\mathrm{class_name}'="SimplePump",'\mathrm{extends}'="Hydraulics.Templates.RotationalComponentTorque",'\mathrm{comment}'="Simple constant displacement pump",'\mathrm{parameters}'=\left\{\mathrm{Dpump}::"Modelica.SIunits.Volume"=1\right\},'\mathrm{omit_annotations}','\mathrm{display}','\mathrm{warning_only}'\right):$
 model SimplePump "Simple constant displacement pump"     extends Hydraulics.Templates.RotationalComponentTorque;     extends Maplesoft.Icons.CustomComponent;     parameter Modelica.SIunits.Volume Dpump = 1; equation     -Dpump * dp / Modelica.Constants.pi = tau;     q = Dpump * w / Modelica.Constants.pi; end SimplePump;