33.3.13 Ungrouped Macro Heat Exchanger Dialog Box

The Ungrouped Macro Heat Exchanger dialog box allows you to set up the ungrouped macro heat exchanger model. See Section  14.3 for details about using this dialog box.

Controls

Fluid Zone   specifies the zone that represents the heat exchanger.

Model Data   contains the parameters related to the heat exchanger model.

Options   allows you to choose one of the following settings:

Fixed Heat Rejection   specifies that ANSYS FLUENT should compute the auxiliary fluid inlet temperature for a specified heat rejection.

Fixed Inlet Temperature   specifies that ANSYS FLUENT should compute the total heat rejection of the core for a given inlet auxiliary temperature.

Heat Transfer Model   allows you to specify either the ntu-model or the simple-effectiveness-model for heat transfer.

Core Porosity Model   contains a drop-down list of all available core porosity models.

Edit...   opens the Core Porosity Model dialog box (see Section  14.3.6).

Heat Exchanger Performance Data   contains the parameters for heat transfer.

Heat Transfer Data...   opens the Heat Transfer Data Table dialog box (see Section  3e). This item will appear for the NTU model only.

Auxiliary Fluid Temperature   specifies the auxiliary fluid temperature. This item will appear only for the NTU model.

Primary Fluid Temperature   specifies the gas stream temperature. This item will appear only for the NTU model.

Velocity Effectiveness Curve...   opens the Velocity Effectiveness Curve dialog box in which you can define the effectiveness of the heat exchanger core ( $\epsilon$ in this equation in the separate Theory Guide). This item will appear for simple effectiveness model only.

Geometry   contains parameters to define the macro grid.

Width   sets the width of the heat exchanger core. The Width is measured in the pass-to-pass direction.

Height   sets the height of the heat exchanger core. The Height is measured in the auxiliary fluid inlet direction.

Depth   sets the depth of the heat exchanger core.

Number of Passes   specifies the number of passes for the macro grid. (See Figure  14.3.6.)

Number of Rows/Pass, Number of Columns/Pass   specify the number of macro rows and columns per pass in the macro grid. (See Figure  14.3.6.)

View Passes   displays the macro grid. (This button becomes available after you click Apply.) The path of the auxiliary fluid is color-coded in the display: macro $0$ is red and macro $n-1$ is blue.

Draw Mesh   toggles between displaying and not displaying the mesh when the macro mesh is displayed (using the View Passes button). The Mesh Display dialog box opens when Draw Mesh is selected.

Update from Plane Tool   updates the Auxiliary Fluid Inlet Direction and Pass-to-Pass Direction from the plane tool orientation. The Width, Height, and Depth will also be updated. See Section  28.6.1 for information about using the plane tool.

Auxiliary Fluid Inlet Direction (height)   specifies the direction in which the auxiliary fluid enters the heat exchanger. See Figure  14.3.6.

Pass-to-Pass Direction (width)   specifies the direction in which the auxiliary fluid moves at the end of each pass through the heat exchanger. See Figure  14.3.6.

Auxiliary Fluid   contains the option to specify the auxiliary fluid properties.

Auxiliary Fluid Properties Method   contains options for specifying auxiliary fluid properties.

constant-specific-heat   allows you to specific a constant value for the auxiliary fluid specific heat.

user-defined-enthalpy   allows you to specify a user-defined function for the auxiliary fluid enthalpy.

Auxiliary Fluid Specific Heat   specifies the value of $c_{p,auxiliary}$ in this equation in the separate Theory Guide. This value is specified only if constant-specific-heat is selected.

Auxiliary Fluid Enthalpy UDF   allows you to specify a UDF for the auxiliary fluid enthalpy (see this equation in the separate Theory Guide). This option is available only when user-defined-enthalpy is selected.

Auxiliary Fluid Flow Rate   sets the flow rate of the auxiliary fluid ( $\dot{m}$ in this equation in the separate Theory Guide).

Heat Rejection   sets the total heat rejection ( $q_{\rm total}$ in this equation in the separate Theory Guide). This value is specified only if Fixed Heat Rejection is selected.

Initial Temperature   sets an initial guess for the inlet temperature ( $T_{_{\rm in}}$ in this equation and this equation in the separate Theory Guide). This value is specified only if Fixed Heat Rejection is selected.

Inlet Temperature   sets the auxiliary fluid initial temperature ( $T_{_{\rm in}}$ in this equation and this equation in the separate Theory Guide). This value is specified only if Fixed Inlet Temperature is selected in the Model Data tab.

Inlet Pressure   sets the auxiliary fluid inlet pressure. This value is specified only if user-defined-enthalpy is selected.

Inlet Quality   specifies the value of $x$ in this equation in the separate Theory Guide. This value is specified only if user-defined-enthalpy is selected.

Pressure Drop   specifies the value of $p_{in}$ in this equation in the separate Theory Guide. This value is specified only if user-defined-enthalpy is selected.

Apply   saves all the settings for the heat exchanger specified in the Fluid Zone list.

Delete   deletes the heat exchanger specified in the Fluid Zone list.