Buildings.Fluids.HeatExchangers.CoolingTowers.BaseClasses

Package Content

Name	Description
PartialStaticTwoPortCoolingTower	Cooling tower with variable speed

Buildings.Fluids.HeatExchangers.CoolingTowers.BaseClasses.PartialStaticTwoPortCoolingTower

Parameters

Type	Name	Default	Description
replaceable package Medium		Modelica.Media.Interfaces.Pa...	Medium in the component
Nominal condition
MassFlowRate	m0_flow		Nominal mass flow rate [kg/s]
Initialization
MassFlowRate	m_flow.start	0	Mass flow rate from port_a to port_b (m_flow > 0 is design flow direction) [kg/s]
Pressure	dp.start	0	Pressure difference between port_a and port_b [Pa]
Assumptions
Boolean	allowFlowReversal	system.allowFlowReversal	= true to allow flow reversal, false restricts to design direction (port_a -> port_b)
Advanced
MassFlowRate	m_flow_small	1E-4*m0_flow	Small mass flow rate for regularization of zero flow [kg/s]
Diagnostics
Boolean	show_V_flow	true	= true, if volume flow rate at inflowing port is computed
Initialization
AbsolutePressure	p_a_start	system.p_start	Guess value for inlet pressure [Pa]
AbsolutePressure	p_b_start	p_a_start	Guess value for outlet pressure [Pa]

Connectors

Type	Name	Description
FluidPort_a	port_a	Fluid connector a (positive design flow direction is from port_a to port_b)
FluidPort_b	port_b	Fluid connector b (positive design flow direction is from port_a to port_b)
input RealInput	TAir	Entering air dry or wet bulb temperature

Modelica definition

model PartialStaticTwoPortCoolingTower 
  "Cooling tower with variable speed"
  extends Fluids.Interfaces.PartialStaticTwoPortHeatMassTransfer;
  extends Buildings.BaseClasses.BaseIcon;
  Modelica.SIunits.Conversions.NonSIunits.Temperature_degC TWatIn_degC(
                                                  start=35) 
    "Water inlet temperature";
  Modelica.SIunits.Conversions.NonSIunits.Temperature_degC TWatOut_degC(
                                                   start=28) 
    "Water outlet temperature";
  Modelica.SIunits.Conversions.NonSIunits.Temperature_degC TAirIn_degC(
                                                  start=25) 
    "Air dry-bulb inlet temperature";
  Modelica.Blocks.Interfaces.RealInput TAir 
    "Entering air dry or wet bulb temperature";
equation 
  TWatIn_degC  = Modelica.SIunits.Conversions.to_degC(sta_a.T);
  TWatOut_degC = Modelica.SIunits.Conversions.to_degC(sta_b.T);
  TAirIn_degC  = Modelica.SIunits.Conversions.to_degC(TAir);

  dp = 0;
  mXi_flow = zeros(Medium.nXi); // no mass added or removed (sensible heat only)

end PartialStaticTwoPortCoolingTower;