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Specification of pressure and internal energy (PU flash)

Compute the properties of a given fluid, at a fixed pressure and internal energy.

Function signature

XLT.REF.FLASH.PU(Fluid, P, U, Properties, [in-units], [out-units])

Function parameters

The function takes the following arguments:

Fluid: TEXT

The name of the fluid. The list of available fluids can be found here.

P: NUMBER

The pressure at which the properties are to be computed. The pressure unit depends on the units specified in the in-units parameter. The default unit is Pa.

U: NUMBER

The internal energy at which the properties are to be computed. The internal energy unit depends on the units specified in the in-units parameter. The default unit is J/kg.

Properties: TEXT or TEXT array

The list of properties to be computed. The list of available properties can be found here.

in-units: TEXT [optional]

A string specifying the units of the temperature and pressure. The default unit is SI. The list of available units can be found here.

out-units: TEXT [optional]

A string specifying the units of the properties. The default unit is SI. The list of available units can be found here.

Function results

Returns a value, or an array of values, corresponding to the list of properties of the fluid at the given pressure and internal energy.

Example usage

The following examples demonstrate the usage of the XLT.REF.FLASH.PU function.

Calculating the enthalpy of water at 101325 Pa and 105000 J/kg

=XLT.REF.FLASH.PU("WATER",101325,105000,"H")
Water PT H

Calculating the enthalpy, entropy, and density of water at 101325 Pa and 105000 J/kg

=XLT.REF.FLASH.PU("WATER",101325,105000,{"H";"S";"RHO"})
Water PT H
Last modified: 17 March 2025