Model for an ideally mixed fluid volume and the ability to store mass and energy. The volume is fixed, and latent and sensible heat can be exchanged.
This model represents the same physics as
IDEAS.Fluid.MixingVolumes.MixingVolume, but in addition, it allows
adding or subtracting water to the control volume.
The mass flow rate of the added or subtracted water is
specified at the port mWat_flow
.
Adding mWat_flow
itself does not affect the energy balance
in this model. Hence, the enthalpy that is added or removed with the
flow of mWat_flow
needs to be added to the heat port
heatPort
.
To increase the numerical robustness of the model, the constant
prescribedHeatFlowRate
can be set by the user.
This constant only has an effect if the model has exactly two fluid ports connected,
and if it is used as a steady-state model.
Use the following settings:
prescribedHeatFlowRate=true
if the only means of heat transfer
at the heatPort
is a prescribed heat flow rate that
is not a function of the temperature difference
between the medium and an ambient temperature. Examples include an ideal electrical heater,
a pump that rejects heat into the fluid stream, or a chiller that removes heat based on a performance curve.
If the heatPort
is not connected, then set prescribedHeatFlowRate=true
as
in this case, heatPort.Q_flow=0
.
prescribedHeatFlowRate=false
if there is heat flow at the heatPort
computed as K * (T-heatPort.T), for some temperature T and some conductance K,
which may itself be a function of temperature or mass flow rate.prescribedHeatFlowRate=false
.
The parameter mSenFac
can be used to increase the thermal mass of this model
without increasing its volume. This way, species concentrations are still calculated
correctly even though the thermal mass increases. The additional thermal mass is calculated
based on the density and the value of the function HeatCapacityCp
of the medium state state_default
.
This parameter can for instance be useful in a pipe model when the developer wants to
lump the pipe thermal mass to the fluid volume. By default mSenFac = 1
, hence
the mass is unchanged. For higher values of mSenFac
, the mass will be scaled proportionally.
Set the parameter use_C_flow = true
to enable an input connector for the trace substance flow rate.
This allows to directly add or subtract trace substances such as
CO2 to the volume.
See
IDEAS.Fluid.Sensors.Examples.PPM
for an example.
initialize_p
to final
so that it does not
appear as a user-selectable parameter. This is done because
initialize_p
has been changed from a constant
to a parameter
for
Buildings, issue 1013.
QSen_flow
and
QLat_flow
.sensibleOnly
in steBal
as this constant is no longer used.
s
to allow this model to also be used
with IDEAS.Media.Water
.
i_w
to avoid a warning in OpenModelica.
IDEAS.Fluid.MixingVolumes.BaseClasses.PartialMixingVolumeWaterPort
.
mXi_flow[Medium.nXi]
to a scalar input connector mWat_flow
in the conservation equation model.
The reason is that mXi_flow
does not allow
to compute the other components in mX_flow
and
therefore leads to an ambiguous use of the model.
By only requesting mWat_flow
, the mass balance
and species balance can be implemented correctly.
cardinality
function.
Therefore, all input signals must be connected.
IDEAS.Fluid.Interfaces
.