14.1.1. Vista TF Setup Cell Properties

The main properties that control Vista TF are associated with the Setup cell. To see the properties, do any one of the following:

  • Right-click the Setup cell and select Edit.

  • Double-click the Setup cell.

  • Right-click the Setup cell and select Properties.

Table 14.1: Vista TF Setup Cell Properties describes each of the cell properties.

Table 14.1: Vista TF Setup Cell Properties

Group

Name

Description

General

Component ID

The name of the cell with which the present set of properties is associated.

Directory Name

This is the system directory name that appears within the project files.

Machine Type

This property appears when there is no cell upstream of the Setup cell; it also appears when the machine type cannot be determined from upstream data.

This property defines the machine type.

The choices are:

  • Pump

  • Axial Compressor

  • Centrifugal Compressor

  • Fan

  • Axial Turbine

  • Radial Turbine

  • Hydraulic Turbine

  • Unknown

This property controls which template files are used and which report is used for the results. You can customize these templates. For details, see Customizing the Vista TF Template Files.

Note that this property does not appear in Throughflow systems because Throughflow systems receive this data from the Geometry cell, which is upstream of the Setup cell.

Number of Blade Rows

This property appears when there is no cell upstream of the Setup cell.

This property defines the number of blade rows in the geometry (.geo) file.

Note that this property does not appear in Throughflow systems because Throughflow systems receive this data from the Geometry cell, which is upstream of the Setup cell.

Solver Settings

Number of Streamlines

This property defines the number of meridional streamlines to use in the calculation. For details, see Specification of the Control Data File (*.con).

Maximum Iterations

This property defines the maximum number of solver iterations. For details, see Specification of the Control Data File (*.con).

Operating Conditions

Machine Rotational Direction

This property defines the direction of rotation of the blades about the Z axis.

The choices are:

  • Right-handed

  • Left-handed

Machine Rotational Speed

This property defines the rotational speed of the machine.

Flow Option

This property specifies the types of boundary conditions.

The choices are:

  • Mass Flow

  • Pressure Ratio

  • Pressure Difference

For details, see Specification of the Control Data File (*.con) and Specification of Aerodynamic Data File (*.aer).

Pressure Ratio

(For Flow Option = Pressure Ratio)

This property defines the outlet-to-inlet ratio of absolute total pressures (each pressure measured in the stationary frame).

Pressure Difference

(For Flow Option = Pressure Difference)

This property defines the outlet-to-inlet difference of total pressures (each pressure measured in the stationary frame).

Mass Flow Rate

This property defines the inlet mass flow rate.

Inlet Total Pressure

This property defines the inlet absolute total pressure (measured in the stationary frame).

Inlet Total Temperature

This property defines the inlet absolute total temperature (measured in the stationary frame).

Inlet Swirl Angle

This property defines the angle of the inlet velocity measured with respect to the meridional plane. A positive angle implies that the flow swirls in the Machine Rotational Direction.

Reference Values

Reference Diameter Option

This property defines the Reference Diameter for all blade rows.

The choices for this property are:

  • Automatic

    This is the default option for new cases. The Reference Diameter is computed automatically based on the geometry of the first rotating blade row. For radial machines, the Reference Diameter is the mean tip diameter of the first impeller. For axial machines, the Reference Diameter is the hub diameter at the trailing edge of the first impeller.

    For case that have inducers, the Automatic option will cause the Reference Diameter to be based on the inducer; this is usually not appropriate. For such cases, you should manually specify the Reference Diameter.

  • User defined

    You specify the Reference Diameter.

The Reference Diameter can also be specified in the aerodynamic data file. For details, see Specification of Aerodynamic Data File (*.aer).

Reference Diameter

(For Reference Diameter Option = User defined)

The Reference Diameter.

Polytropic Efficiency

This property defines the small-scale polytropic efficiency for the machine.

Fluid Properties

Fluid Option

This property defines the type of fluid that flows through the machine.

The choices for this property are:

  • Ideal Gas

  • Real Gas

  • Liquid

Gas Specific Heat Cp

(For Fluid Option = Ideal Gas)

This property defines the specific heat capacity (at constant pressure) of the ideal gas.

Specific Heat Ratio

(For Fluid Option = Ideal Gas)

This property defines the specific heat ratio of the ideal gas.

Material

(For Fluid Option = Real Gas)

This property is used to specify a real gas from a list of available real gases. You can select Custom to specify a custom real gas property file. The equivalent real gas files for the standard materials appear in the Ansys installation under Ansys Inc/v242/Addins/VistaTF/RealGas and can be used as a starting point for you to generate your own custom real gas files. The format of the real gas files is described in Specification of the Real Gas Properties Data File (*.rgp) in the TurboSystem User's Guide.

Fluid Density

(For Fluid Option = Liquid)

This property defines the density of the liquid.

Fluid Specific Heat

(For Fluid Option = Liquid)

This property defines the specific heat capacity of the liquid.

Dynamic Viscosity

This property indicates the dynamic viscosity of the fluid as follows:

  • A value less than 1 [N s m^-2] (or equivalent value in other units) is interpreted as the dynamic viscosity. Note that the value must be greater than 0.0000001 [N s m^-2].

  • A value of 0 causes Vista TF to calculate the dynamic viscosity from a built-in equation for dynamic viscosity based on Sutherland’s law and the Inlet Total Temperature. This works only for an ideal gas.

  • A value greater than 1 [N s m^-2] (or equivalent value in other units) is interpreted as the Reynolds number, in which case Vista TF calculates the dynamic viscosity using this Reynolds number, the Reference Diameter, the Machine Rotational Speed, and the fluid density.

Initial Conditions

Initial Cm/U_ref

This property serves as an initial guess for the meridional velocity divided by a characteristic velocity, where the latter is half the Reference Diameter multiplied by the Machine Rotational Speed. For more information, see the description for cm_start in Specification of the Control Data File (*.con).