ES_StableIF97 AddIn

Syntax of Steam Table Functions

Even though ES_StableIF97 AddIn steam table functions can be embedded into Excel easily by using "ES_StableIF97 AddIn Function" Form, the user had better know about the syntax of the functions in order to edit or manipulate the functions in Excel.

For the list of ES_StableIF97 AddIn steam table functions, please see Function Summary.

Steam Table Functions

Steam table functions have a common structure of syntax consisting of the following characters in sequence.   It is helpful to remind ES_StabelIF97 AddIn functions of "ESStb_HbyPT(Press, Temp, PUN, TUN, HUN)" and "ESStb_PsatbyT(Temp, TUN, PUN)" to understand the following explanation.

1) "ESStb_" Prefix  

All ES_StableIF97 AddIn functions have "ESStb_" prefix that represent ENGSoft Steam Table.

2) Output Property Character

The first character(or character string) after the prefix is output property character.   Please refer to the Property Character List below.   

For saturation pressure and temperature, "sat" character string is followed after the output property characters "P" and "T".

For liquid and vapor states in saturation condition, "f' character for liquid or "g" character for vapor is followed after the output property character.

For the metastable vapor functions, the prefix of "Meta" is attached in front of the output property character.

3) "by" Divider

After the output property character, "by" divider is followed for division between the characters of output and input properties.    

4) Input Property Characters

After the "by" divider, input property characters are followed.   For the input property characters, the same property characters are used for input properties.

The function that have only one input property has one input property character.    The function "ESStb_PsatbyT(Temp, TUN, PUN)" is an example, which returns saturation pressure by temperature input.

 

All steam table functions of ES_StableIF97 AddIn has the name consisting of the strings in sequence explained above.   After the function name, the arguments of the functions are followed in a parenthesis in the following sequence.

5) The First Input Property Value Argument

The first argument is the first input property value.   In case of the function "ESStb_HbyPT", the first argument following "by" divider is pressure that is the first input property in the function name.   The input property value can be directly input into the first argument position or the Excel cell address having the input property value can be input into the argument position.

6) The Second Input Property Value Argument

The second argument is the second input property value.   In case of the function "ESStb_HbyPT", the second argument is temperature that is the second input property in the function name.     The input property value can be directly input into the second argument position or the Excel cell address having the input property value can be input into the argument position.

The second input property value argument does not exist in the functions that have single input property, such as the function "ESStb_PsatbyT".

7) Unit Number Arguments for the Input Properties

The arguments following the first and second input property value arguments, are the unit number arguments  for the first and second input properties.    In case of the function "ESStb_HbyPT", the unit number arguments for the first and second input properties are pressure and temperature unit numbers that are the first and second input properties of the function.   

The unit number can be directly input into the unit number argument position or the Excel cell address having the input property value can be input into the argument position.

In the syntax expression of the functions, the abbreviated names for the unit number arguments are used, such as PUN for pressure unit number and TUN for temperature unit number.   For the abbreviation, please refer to the Unit Number Argument Abbreviation List below.

The second unit number argument does not exist in the functions that have single input property, such as the function "ESStb_PsatbyT".   

8) Unit Number Argument for the Output Property

The last argument in the argument parenthesis is the unit number argument for the output property.    In case of the function "ESStb_HbyPT", the unit number arguments for the output property is enthalpy unit numbers that are the output property of the function.

The unit number can be directly input into the unit number argument position or the Excel cell address having the input property value can be input into the argument position.

In the syntax expression of the functions, the abbreviated names for the unit number arguments are used, too. such as HUN for enthalpy.   For the abbreviation, please refer to the Unit Number Argument Abbreviation List below.

There are some specific functions that have only one unit number argument for input properties even though it has two input properties.   Those are ;

Please note that in case of nozzle functions, nozzle outlet pressure having the argument name of "Press2" is required as the third input property value argument.

If unit number arguments are omitted, default number of zero(0) is used.   Zero(0) unit numbers of properties are mainly MKS units.  For property unit numbers, please refer to Unit Summary.

 

Syntax of "ESStb_HbyPT" Function (Sample)

Returns enthalpy by pressure and temperature inputs.

Syntax :

ESStb_HbyPT(Press, Temp, PUN, TUN, HUN)

 Arguments :

Examples :

ESStb_HbyPT($F$3,$F$2,$C$5,$C$6,$C$8) returns enthalpy at pressure value in cell "F3" and temperature value in cell "F2".   The pressure input unit number is the value in cell "C5", temperature input unit number in cell "C6" and enthalpy output unit number in cell "C8".   In the function, the cell addresses were given in absolute type with "$" marks in front of cell column characters and row numbers.

ESStb_HbyPT(100,500,2,2,1) returns 977.2139101 kJ/kg enthalpy at 100 bara pressure and 500 K temperature.   The first argument in parenthesis "100" is pressure input value and the second argument "500" is temperature input value.   The next "2" is pressure input unit number representing "bar a" unit; the next "2" is temperature input unit number representing "oK" unit; and the next "1" is enthalpy output unit number representing "kJ/kg" unit.

 

 Steam Table Function Remarks

1) In case that quality(X) is one of input arguments and the quality value given is less than 0 or greater than 1, the error output "#ES/XErr!" is returned.

2) In case that the function output is quality(X) like "ESStb_XbyPH" function and the state given is sub-cooled water or superheated steam, the number "2" is returned as the output value.

 

 

Syntax of Auxiliary Functions

Even though ES_StableIF97 AddIn auxiliary functions can be embedded into Excel easily by using "ES_StableIF97 AddIn Function" Form, the user had better know about the syntax of the functions in order to edit or manipulate the functions in Excel.

For the list of ES_Stable AddIn auxiliary functions, please see Function Summry.

Unit Conversion Functions

Unit conversion functions have a common structure of syntax consisting of the following characters in sequence.   It is helpful to remind ES_StabelIF97 AddIn unit conversion function of "ESStb_CvtP(Press, SourcePUN, OutputPUN)" to understand the following explanation.

"ESStb_" Prefix  

All ES_StableIF97 AddIn functions have "ESStb_" prefix that represent ENGSoft Steam Table.

"Cvt" Prefix 

All unit conversion functions have "Cvt" prefix following "ESStb_" prefix that represent Convert.

Conversion Property Character

The first character(or character string) after the "Cvt" prefix is the conversion property character..   Please refer to the Property Character List below.

The characters explained above consist of the function name.   After the function name, the arguments of the functions are followed in a parenthesis in the following sequence.

The Conversion Property Value Argument

The first argument is the conversion property value.   In case of the function "ESStb_CvtP", the conversion property value is pressure value, of which value will be converted from one pressure unit to another(or same) pressure unit.

Source Unit Number Argument

The argument following the conversion property value argument is the source unit number argument corresponding to the unit of the conversion property value argument described above.    In case of the function "ESStb_CvtP", the source unit number argument shall be one of pressure unit numbers, because the conversion property is pressure.

In the syntax expression of the functions, the abbreviated names for the unit number arguments are used with "Source" prefix., such as SouucePUN for pressure unit number.   For the abbreviation, please refer to the Unit Number Argument Abbreviation List below.

Output Unit Number Argument

The argument following the source unit number argument is the output unit number argument also corresponding to the unit of the conversion property argument.    In case of the function "ESStb_CvtP", the output unit number argument shall be one of pressure unit numbers, because the conversion property is pressure.

In the syntax expression of the functions, the abbreviated names for the unit number arguments are used with "Output" prefix., such as OutputPUN for pressure unit number.   For the abbreviation, please refer to the Unit Number Argument Abbreviation List below.

 

Unit String Functions

Unit string functions have a common structure of syntax consisting of the following characters in sequence.   It is helpful to remind ES_StabelIF97 AddIn unit conversion function of "ESStb_PUnitStr(PUN)" to understand the following explanation.

"ESStb_" Prefix  

All ES_StableIF97 AddIn functions have "ESStb_" prefix that represent ENGSoft Steam Table.

Function Character for Unit String

The first character(or character string) following the "ESStb_" prefix is the Function Character for unit string.   Please refer to the Function Character List below.

"UnitStr" Postfix 

All unit string functions have "UnitStr" postfix following the Function Character for unit string.   The "UnitStr" postfix represents Unit String.

The characters explained above consist of the function name.   After the function name, the argument for unit number is followed in a parenthesis.

Unit Number Argument

The only one argument in the parenthesis is the unit number argument to return unit string.    In case of the function "ESStb_PUnitStr", the unit number argument shall be one of pressure unit numbers.

In the syntax expression of the functions, the abbreviated names for the unit number arguments are used, such as PUN for pressure unit number.   For the abbreviation, please refer to the Unit Number Argument Abbreviation List below.

 

Syntax of "ESStb_CvtP" Function (Sample)

Returns converted pressure value from one pressure unit to another(or same) pressure unit.

Syntax :

ESStb_CvtP(Press, SoucePUN, OutputPUN)

 Arguments :

 Examples :

ESStb_CvtP($F$3,0,$C$5) returns pressure in the pressure unit number(OutputPUN) in cell "C5" converted from the pressure in cell "'F3" in the pressure unit number(SourcePUN) "0".   Pressure unit number "0" represents "kg/cm2 a".   In the function, the cell addresses were given in absolute type with "$" marks in front of cell column characters and row numbers.

ESStb_CvtP(100,0,6) returns 1422.334331 psia pressure converted from 100 kg/cm2 a pressure.   In the function, "100" pressure value is in source unit number "0" that represents "kg/cm2 a" unit.   The output unit number "6" represents "psia" unit.

 

Syntax of "ESStb_PUnitStr" Function (Sample)

Returns pressure unit string corresponding to a pressure unit number.

Syntax :

ESStb_PUnitStr(PUN)

 Arguments :

Examples :

ESStb_PUnitStr($C$5) returns pressure unit string in the pressure unit number(PUN) in cell "C5".   In the function, the cell addresses were given in absolute type with "$" marks in front of cell column characters and row numbers.

ESStb_PUnitStr(6) returns "psi a" string.   In the function the output unit number "6" represents "psi a" unit.

 

Property Character(or Character String) List

P

: Pressure

T

: Temperature

V

: Specific Volume

H

: Enthalpy

S

: Entropy

Visco

: Dynamic Viscosity

ViscoX

: Kinematic Viscosity

IntEnergy

: Internal Energy

Cp

: Specific Isobaric Heat Capacity

Cv

: Specific Isochoric Heat Capacity

SoundSpd

: Speed of Sound

ThCond

: Thermal Conductivity

X

: Quality

 

 

WperA

: Mass Flow Rate per Nozzle Throat Unit Area

Vel

: Velocity at Nozzle Throat

 Unit Number Argument Abbreviation List

PUN

: Pressure Unit Number

TUN

: Temperature Unit Number

VUN

: Specific Volume Unit Number

HUN

: Enthalpy Unit Number

SUN

: Entropy Unit Number

ViscoUN

: Dynamic Viscosity Unit Number

ViscoXUN

: Kinematic Viscosity Unit Number

VelUN

: Velocity Unit Number

ThCondUN

: Thermal Conductivity Unit Number

 

 

MFlowUN

: Mass Flow Rate Unit Number

AreaUN

: Area Unit Number

 


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