XSteam for julia

Immigrate By hzgzh Date: 2019-9-29

X Steam for julia is a implementation of the IAPWS IF97 standard formulation immigrate from XSteam for matlab By Magnus Holmgren, www.x-eng.com The steam tables are free and provided as is. We take no responsibilities for any errors in the code or damage thereby. You are free to use, modify and distribute the code as long as authorship is properly acknowledged. Please notify me at magnus@x-eng.com if the code is used in commercial applications. It provides accurate data for water and steam and mixtures of water and steam properties from 0 - 1000 bar and from 0 - 2000 deg C.

The initial units of XSteam are SI units as denoted in this document. All functions however call unit conversion functions so the units can be easily changed. A text file with unit conversion functions for English units are enclosed with the file.

Usage

The XSteam code are used in the following way:

• Example: rho_pT(1,200) returns the density at 1 bar and 200°C.
• winsteam syntax pth(1,200) returns the entalpy at 1bar and 200°C

Introduction

X Steam for matlab is a implementation of the IAPWS IF97 standard formulation. It provides accurate thermo hydraulic data for water and steam and mixtures of water and steam in the region:

• 0°C < temperature < 2000°C for
• 0.00611 bar a < pressure < 100 bar a
• 0°C < temperature < 1000°C for
• 0.00611 bar a < pressure < 1000 bar a

For accuracy and further information on IAPWS IF97 formulation, se homepage of the international association for properties of water and steam (www.iapws.org).

Unit

Notation	Quantity	Unit
T	Temperature	°C
p	Pressure	bar
h	Enthalpy	kJ/kg
v	Specific volume	$m^3/kg$
rho	Density	$kg/m^3$
s	Specific entropy	kJ/(kg °C)
u	Specific internal energy	kJ/kg
Cp	Specific isobaric heat capacity	kJ/(kg °C)
Cv	Specific isochoric heat capacity	kJ/(kg °C)
w	Speed of sound	m/s
my	Viscosity	Pa s
tc	Thermal Conductivity	W/(m °C)
st	Surface Tension	N/m
x or q	Vapour fraction (0-1)	-
vx	Vapour Volume Fraction (0-1)	-

XSteam functions

Temperature

Function	In1	In2	Out
Tsat_p or pt	p		Saturation temperature
T_ph or pht	p	H	Temperture as a function of pressure and enthalpy
T_ps or pst	p	S	Temperture as a function of pressure and entropy
T_hs or hst	h	S	Temperture as a function of enthalpy and entropy

Pressure

Function	In1	In2	Out
psat_T or tp	T		Saturation pressure
p_hs or hsp	h	s	Pressure as a function of h and s.
p_hrho or hvp	h	rho	Pressure as a function of h and rho (density) or Specific volume .Very unaccurate for solid water region since it's almost incompressible!

Enthalpy

Function	In1	In2	Out
hV_p or pqh(p,1)	p		Saturated vapour enthalpy
hL_p or pqh(p,0)	p		Saturated liquid enthalpy
hV_T or tqh(t,1)	T		Saturated vapour enthalpy
hL_T or tqh(t,0)	T		Saturated liquid enthalpy
h_pT or pth	p	T	Entalpy as a function of pressure and temperature.
h_ps or psh	p	s	Entalpy as a function of pressure and entropy.
h_px or pqh	p	x	Entalpy as a function of pressure and vapour fraction
h_Tx or tqh	T	X	Entalpy as a function of temperature and vapour fraction
h_prho or pvh	p	rho	Entalpy as a function of pressure and density or Specific volume. Observe for low temperatures (liquid) this equation has 2 solutions.(Not valid!!)

Specific volume

Function	In1	In2	Out
vV_p or pqv(p,1)	p		Saturated vapour volume
vL_p or pqv(p,0)	p		Saturated liquid volume
vV_T or tqv(p,1)	T		Saturated vapour volume
vL_T or tqv(p,0)	T		Saturated liquid volume
v_pT or ptv	p	T	Specific volume as a function of pressure and temperature.
v_ph or phv	p	h	Specific volume as a function of pressure and enthalpy
v_ps or psv	p	s	Specific volume as a function of pressure and entropy.

Density

Function	In1	In2	Out
rhoV_p or 1/pqv(p,1)	p		Saturated vapour density
rhoL_p or 1/pqv(p,0)	p		Saturated liquid density
rhoV_T or 1/tqv(t,1)	T		Saturated vapour density
rhoL_T or 1/tqv(t,0)	T		Saturated liquid density
rho_pT or 1/ptv	p	T	Density as a function of pressure and temperature.
rho_ph or 1/phv	p	h	Density as a function of pressure and enthalpy
rho_ps or 1/psv	p	s	Density as a function of pressure and entropy.

Specific entropy

Function	In1	In2	Out
sV_p or pqs(p,1)	p		Saturated vapour entropy
sL_p or pqs(p,0)	p		Saturated liquid entropy
sV_T or tqs(p,1)	T		Saturated vapour entropy
sL_T or tqs(p,0)	T		Saturated liquid entropy
s_pT or pts	p	T	Specific entropy as a function of pressure and temperature(Returns saturated vapour entalpy if mixture.)
s_ph or phs	p	h	Specific entropy as a function of pressure and enthalpy

Specific internal energy

Function	In1	In2	Out
uV_p or pqu(p,1)	p		Saturated vapour internal energy
uL_p or pqu(p,0)	p		Saturated liquid internal energy
uV_T or tqu(t,1)	T		Saturated vapour internal energy
uL_T or tqu(t,0)	T		Saturated liquid internal energy
u_pT or ptu	p	T	Specific internal energy as a function of pressure and temperature.
u_ph or phu	p	h	Specific internal energy as a function of pressure and enthalpy
u_ps or psu	p	s	Specific internal energy as a function of pressure and entropy.

Specific isobaric heat capacity

Function	In1	In2	Out
CpV_p or pqc(p,1)	p		Saturated vapour heat capacity
CpL_p or pqc(p,0)	p		Saturated liquid heat capacity
CpV_T or tqc(t,1)	T		Saturated vapour heat capacity
CpL_T or tqc(t,0)	T		Saturated liquid heat capacity
Cp_pT or ptc	p	T	Specific isobaric heat capacity as a function of pressure and temperature.
Cp_ph or phc	p	h	Specific isobaric heat capacity as a function of pressure and enthalpy
Cp_ps or psc	p	s	Specific isobaric heat capacity as a function of pressure and entropy.

Specific isochoric heat capacity

Function	In1	In2	Out
CvV_p	p		Saturated vapour isochoric heat capacity
CvL_p	p		Saturated liquid isochoric heat capacity
CvV_T	T		Saturated vapour isochoric heat capacity
CvL_T	T		Saturated liquid isochoric heat capacity
Cv_pT	p	T	Specific isochoric heat capacity as a function of pressure and temperature.
Cv_ph	p	h	Specific isochoric heat capacity as a function of pressure and enthalpy
Cv_ps	p	s	Specific isochoric heat capacity as a function of pressure and entropy.

Speed of sound

Function	In1	In2	Out
wV_p or pqw(p,1)	p		Saturated vapour speed of sound
wL_p or pqw(p,0)	p		Saturated liquid speed of sound
wV_T or tqw(t,1)	T		Saturated vapour speed of sound
wL_T or tqw(t,0)	T		Saturated liquid speed of sound
w_pT or ptw	p	T	Speed of sound as a function of pressure and temperature.
w_ph or phw	p	h	Speed of sound as a function of pressure and enthalpy
w_ps or psw	p	s	Speed of sound as a function of pressure and entropy.

Viscosity

Viscosity is not part of IAPWS Steam IF97. Equations from "Revised Release on the IAPWS Formulation 1985 for the Viscosity of Ordinary Water Substance", 2003 are used. Viscosity in the mixed region (4) is interpolated according to the density. This is not true since it will be two fases.

Function	In1	In2	Out
my_pT or ptm	p	T	Viscosity as a function of pressure and temperature.
my_ph or phm	p	h	Viscosity as a function of pressure and enthalpy
my_ps or psm	p	s	Viscosity as a function of pressure and entropy.
pqm	p	q	Viscosity as a function of pressure and quality.

Thermal Conductivity

Revised release on the IAPS Formulation 1985 for the Thermal Conductivity of ordinary water substance (IAPWS 1998)

Function	In1	In2	Out
tcL_p or pqk(p,1)	p		Saturated vapour thermal conductivity
tcV_p or pqk(p,0)	p		Saturated liquid thermal conductivity
tcL_T or tqk(t,1)	T		Saturated vapour thermal conductivity
tcV_T or tqk(t,0)	T		Saturated liquid thermal conductivity
tc_pT or ptk	p	T	Thermal conductivity as a function of pressure and temperature.
tc_ph or phk	p	h	Thermal conductivity as a function of pressure and enthalpy
tc_hs or hsk	h	s	Thermal conductivity as a function of enthalpy and entropy

Surface Tension

IAPWS Release on Surface Tension of Ordinary Water Substance,September 1994

Function	In1	In2	Out
st_T	T		Surface tension for two phase water/steam as a function of T
st_p	p		Surface tension for two phase water/steam as a function of T

Vapour fraction

Function	In1	In2	Out
x_ph or phq	p	h	Vapour fraction for two phase water/steam as a function of T
x_ps or psq	p	s	Vapour fraction for two phase water/steam as a function of T

Vapour Volume Fraction

Observe that vapour volume fraction is very sensitive. Vapour volume is about 1000 times greater than liquid volume and therefore vapour volume fraction gets close to the accurancy of IAPWS IF-97

Function	In1	In2	Out
vx_ph	p	h	Vapour volume fraction as a function of pressure and enthalpy
vx_ps	p	s	Vapour volume fraction as a function of pressure and entropy.