recordGeneric
Generic data record for thermal wheels
Extends from Modelica.Icons.Record (Icon for records).
Information
Record containing performance-related parameters for thermal wheels.
It is used as a template of performance data for the thermal wheel models in Buildings.Fluid.HeatExchangers.ThermalWheels.BaseClasses.
The record contains the parameters, including the nominal mass flow rates, nominal pressure drops, the heat exchanger effectiveness at part load (75% of the nominal supply flow rate) and at nominal conditions, and the wheel power consumption at the nominal wheel speed.
For the variable-speed thermal wheel (have_varSpe=true), the record also includes the following datasets:
- motor percent full-load efficiency versus wheel speed ratio,
- sensible heat exchange effectiveness corrections versus wheel speed ratio,
- latent heat exchange effectiveness corrections versus wheel speed ratio.
Note the following:
- The heat exchange effectiveness corrections versus wheel speed ratio are correction factors that are multiplied with the heat exchange effectiveness that the wheel has a full rotational speed.
-
When
have_latHEX=true, the dataset of the latent heat exchange effectiveness corrections versus wheel speed ratio is enabled, -
When
use_defaultMotorEfficiencyCurve=true, the motor percent full-load efficiency versus wheel speed ratio is disabled, and the default curve (see Buildings.Fluid.Movers.BaseClasses.Characteristics.motorEfficiencyCurve) is used for calculations.
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Boolean | have_latHEX | true | Set to true to compute latent heat exchange |
| Boolean | use_defaultMotorEfficiencyCurve | true | Set to true to use default motor efficiency curve |
| Boolean | have_varSpe | true | Set to true for the heat recovery wheel with a variable speed drive |
| Nominal condition | |||
| Modelica.Units.SI.MassFlowRate | mSup_flow_nominal | Nominal supply air mass flow rate | |
| Modelica.Units.SI.MassFlowRate | mExh_flow_nominal | Nominal exhaust air mass flow rate | |
| Modelica.Units.SI.PressureDifference | dpSup_nominal | 500 | Nominal supply air pressure drop across the heat exchanger |
| Modelica.Units.SI.PressureDifference | dpExh_nominal | dpSup_nominal | Nominal exhaust air pressure drop across the heat exchanger |
| Real | P_nominal | 100 | Power consumption at the design condition |
| Modelica.Units.SI.Efficiency | epsSen_nominal | 0.8 | Nominal sensible heat exchanger effectiveness |
| Modelica.Units.SI.Efficiency | epsLat_nominal | 0.8 | Nominal latent heat exchanger effectiveness |
| Part load effectiveness | |||
| Modelica.Units.SI.Efficiency | epsSenPL | 0.75 | Part load (75% of the nominal supply flow rate) sensible heat exchanger effectiveness |
| Modelica.Units.SI.Efficiency | epsLatPL | 0.75 | Part load (75% of the nominal supply mass flow rate) latent heat exchanger effectiveness |
| Heat exchange effectiveness computation | |||
| Buildings.Fluid.HeatExchangers.ThermalWheels.Data.Characteristics.HeatExchangerEffectiveness | senEff | Multiplication factor for sensible heat exchange effectiveness due to wheel speed ratio between 0 and 1 | |
| Buildings.Fluid.HeatExchangers.ThermalWheels.Data.Characteristics.HeatExchangerEffectiveness | latEff | Multiplication factor for latent heat exchange effectiveness due to wheel speed ratio between 0 and 1 | |
| Power computation | |||
| Buildings.Fluid.HeatExchangers.ThermalWheels.Data.Characteristics.MotorEfficiency | relMotEff | Ratio of the motor efficiency at give speed to the one when the speed is 1 | |
| Buildings.Fluid.Movers.BaseClasses.Characteristics.efficiencyParameters_yMot | relMotEff_default | Buildings.Fluid.Movers.BaseClasses.Characteristics.motorEfficiencyCurve(P_nominal = P_nominal, eta_max = 1) | Default relative motor efficiency |
Revisions
-
May 28, 2024, by Sen Huang:
First implementation.