X Steam, Thermodynamic properties of water and steam.

Water properties A complete IAPWS IF-97 standard.

Description

www.x-eng.com, Steam and water properties for Matlab based on the "International Association for Properties of Water and Steam Industrial Formulation 1997 (IAPWS IF-97). A full implementation of the IF-97 standard that provides very accurate steam and water properties in ranges from 0-1000 bar and 0-2000°C. Provided thermodynamic properties are:

Temperature
Pressure
Enthalpy
Specific volume
Density
Specific entropy
Specific internal energy
Specific isobaric heat capacity
Specific isochoric heat capacity
Speed of sound
Viscosity
Vapour fraction

All properties can be calculated with the inputs, p and T known, p and h known, h and s known and some with pressure and density known. X Steam are a full implementation of the IF-97 formulation including all regions and all backward functions for good calculation speed. The code are speed optimized with pressure and enthalpy as inputs for dynamic simulations.

Examples:
XSteam('h_pt',1,20) return the enthalpy of water at 1 bar and 20 degC. 84.0118 kJ/kg

XSteam('rho_ph',1,3000) return the density of steam at 1 bar and 3000 kJ/kg. 0.4056 kg/m3

XSteam('w_pt',1,20) returns the speed of sound at 1 bar and 20 deg C. 1483.4 m/s

XSteam('tSat_p',1) returns the saturation temperature at 1 bar. 99.6059 deg C

The X Steam Tables are the perfect tool both for replacing paper tables and for advanced calculations. The X Steam tables are open source and free of charge.

The X Steam tables are also available as MS Excel scripts, OOo Sripts, Dynamic Link Libary .DLL. Please visit www.x-eng.com.

New version 2.5

• Acknowledgements: This submission has inspired the following:; Ideal Rankine Cycle GUI, IAPWS_IF97 functional form with no slip
• MATLAB release: MATLAB 6.0 (R12)
• Other requirements: None.

[urs (us) schwarz]

really nice result of a project
- extraordinary help (including PDF, to boot)
it would be even nicer
- if it was vectorized
- if the spiffy figure could be reproduced easily (see above)
- if the ...XSteam macros for MS Excel... (as mentioned in the help section) came with the package
but this is just ranting a bit
us

[John D'Errico]

If you were to call this inside a long loop, the lack of vectorization might slow things down. However, thats the only reason why I might choose to downrate this at all. The documentation is far above average, so its still a 5 in my book.

[Johan Karlsson]

Simple and gives exact accurate results.

[Magnus Holmgren]

I finally succeded in adding my file and I appriciate all the positive ratings the first day.
I'll consider to vectorize the functions.
The X Steam for MS Excel and the "spiffy figure" is also open source and can be downloaded from www.x-eng.com but I will add them to the ZIP file the next time I update it.

[urs (us) schwarz]

it's ok - BUT (and this is a big BUT) - in the future, do NOT give your OWN submission(s) a rating of 5/5; some people might get really offended and nasty with this inappropriate behavior
us

[Duane Hanselman]

1 star just to balance the author giving himself a 5 star rating. Thanks for the advice Urs!

[John McKenzie]

Water data that really will save me a lot of work writing tables for interpolation into my program. A really great program!
I have two minor improvements:
 - I would like the different functions as separate m files rather than commands.
 - I agree with the previous reviewers that it would nice if the functions where vectorized.
However that?s minor problems, the program does what it?s supposed to and it?s simple to use and well structured. The program is worth a five star.

[donghui zheng]

 

[Mike Baldea]

Excellent work. Thank you.

[Tamir Suliman]

Great program and excellent structure.

[Jeff Buske]

very nice piece of work! Well done.

[Poomjai Sa-adchom]

I like this program

[zhu jian]

General Conmments

[Dave Abramovich]

Very useful. Author must have had a lot of spare time, 150kb of code isn't a few hours job.

[TATEK ZEWDIR]

I NEED HELP.................

[Jim Mechell]

This is an extraordinary and excellent effort. In particular the ablity to obtain properties as functions P and h, h and s.
However it is not clear how the author has stated that properties can be found upto 2000 degree celcius if they are based on IF 97. These to my knowledge are applicable upto 800 degree celcius only. Students would still require a compact printed steam table that they can carry to a test or examination.An excellent new one called "Engineering Steam Tables"by Ashok Malhotra is now available for the purpose at Amazon.com. (type the title in their search box to locae it)

[Giovani Tonel]

On line 1428 ==> err=check();

[pippo pluto]

 

[mohammad kazemi]

 

[David Andersson]

Perfect.
Simple, exact.

[Allan Zadiraka]

Very happy to find steam properties as good as this. Saved me from having to create my own again. Only problem is the temperature lines not breaking at the saturation line on ph diagrams (in english units)at higher pressures; sat line at 3097 psia gives 989.2 BTU/Lb versus 981.5 BTU/Lb for 3097 psia and 700F.

[Magnus Holmgren]

Comment to review bellow. Temperature lines does off course break at the saturation line on ph diagrams. (However h_pt is not valid for mixtures of steam and water since temperature do not vary with enthalpy in that region. Answer becomes NaN. Temperature can?t be the saturation temp of p since then h is undefined.) I think you mixed up the numbers a little to.

XSteamUS('pSat_t',700) = 3.0928896229137e+03 psia
XSteamUS('hV_t',700) = 9.9063684424454e+02 btu/lb
XSteamUS('hV_p',3.0928896229137e+03) = 9.9063684424454e+02 btu/lb

[mario lebbe]

 

[Jonas Andersson]

Just what I need

[Bogdan Marcu]

Exactly what I needed, many thanks

[Lourenco Crawford]

very good!! thank you very much!

[Lourenco Crawford]

very good!! thank you very much!

[William Hounks]

Beau travail

[Xiangbin zhu]

Thanks a lot!

[ashek ullah]

So many thank for your information?

[aman brar]

Awesome...This is exactly what I was looking for.

[Patrik]

Solid and precise, thank you.

[Jason Wang]

OMG. This program saves me so much time on each thermodynamics homework. Thanks so much!

[Morgan May]

Very awesome, I was working on something similar myself, when i stumbled upon this. Talk about a time saver, I do have one question, in line 2496 Should the program read High_Bound = 2563.59200e+5 instead of High_Bound = 2563.592004+5?? Just curious.

[Andrea Baricci]

 

[Mark Mikofski]

Thank you Magnus Holmgren for you outstanding work! Using your work as a inspiration, I completely re-coded all of the IAPWS IF97 (except region 5) and including some of the most recent documentation including thermodynamic derivatives which I needed for some non-linear 2-phase modeling. I have finally posted it here:
http://www.mathworks.com/matlabcentral/fileexchange/35710-iapwsif97-functional-form-with-no-slip
It is vectorized and fully tested, according to the test points in IF97 and accompanying documents and the numerous simulations I have performed using it. I hope you find it as useful as I have.

[Andrew Yablokov]

How to use XSteam in Simulink?