modelCounterFlowNTU
Counter flow heat exchanger using the epsilon-NTU method
Extends from ThermofluidStream.HeatExchangers.Internal.PartialNTU (Partial heat exchanger model using the epsilon-NTU method).
Information
Basic model of a counter-flow heat exchanger based on the effectiveness-NTU method.
The equations are derived from the generic effectiveness-NTU relations which can be found in the "VDI Wärmeatlas" and noumerous standard literature.
For stream dominated applications the following assumptions are made for mass flow regularization close to zero:
- if the mass flow on both sides of the heat exchanger is zero, no heat is transferred
Heat exchanger time constant
See the documentation of the model PartialNTU for further information.
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| String | instanceName (from DropOfCommonsPlus) | getInstanceName() | Instance name |
| SI.Area | A (from PartialNTU) | Heat transfer area | |
| SI.CoefficientOfHeatTransfer | k_NTU (from PartialNTU) | 50 | Overall heat transfer coefficient |
| SI.Time | TC (from PartialNTU) | 0.01 | Heat exchanger time constant (increase as recommended in the documentation) |
| Boolean | d1A (from PartialNTU) | displayParameters and displayArea | displayArea at position 1 |
| Boolean | d1kNTU (from PartialNTU) | displayParameters and displaykNTU and not d1A | displaykNTU at position 1 |
| Boolean | d2kNTU (from PartialNTU) | displayParameters and displaykNTU and not d1kNTU | displaykNTU at position 2 |
| Layout | |||
| Boolean | displayInstanceName (from DropOfCommonsPlus) | dropOfCommons.displayInstanceNames | = true, if instance name is displayed |
| Boolean | displayParameters (from DropOfCommonsPlus) | dropOfCommons.displayParameters | = true, if displaying parameters is enabled |
| Advanced | |||
| Utilities.Units.Inertance | L (from PartialNTU) | dropOfCommons.L | Inertance |
| Advanced › Regularization parameters | |||
| SI.MassFlowRate | m_flow_reg (from PartialNTU) | dropOfCommons.m_flow_reg | Nominal mass flow rate for regularization |
| Layout › Display parameters | |||
| Boolean | displayArea (from PartialNTU) | true | = true, if the heat transfer area A is displayed |
| Boolean | displaykNTU (from PartialNTU) | true | = true, if the overall heat transfer coefficient k_NTU is displayed |
Connectors
| Type | Name | Default | Description |
|---|---|---|---|
| ThermofluidStream.Interfaces.Inlet | inletA | ||
| ThermofluidStream.Interfaces.Outlet | outletA | ||
| ThermofluidStream.Interfaces.Inlet | inletB | ||
| ThermofluidStream.Interfaces.Outlet | outletB |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| SI.TemperatureDifference | Delta_T_max (from PartialNTU) | Maximum temperature difference | |
| MediumA.SpecificEnthalpy | dh_A (from PartialNTU) | Specific enthalpy difference medium A | |
| MediumB.SpecificEnthalpy | dh_B (from PartialNTU) | Specific enthalpy difference medium B | |
| SI.HeatFlowRate | q_flow (from PartialNTU) | Heat flow rate A to B (Q_flow) | |
| Real | effectiveness (from PartialNTU) | Heat exchanger efficiency | |
| Real | NTU (from PartialNTU) | Number of transfer units | |
| MediumA.Temperature | T_in_MediumA (from PartialNTU) | Inlet temperature of medium A | |
| MediumB.Temperature | T_in_MediumB (from PartialNTU) | Inlet temperature of medium B | |
| ThermofluidStream.HeatExchangers.Internal.DiscretizedHEXSummary | summary (from PartialNTU) | Summary record of quantities |