Steam Table Generation
for
Turbine and Receiver / Boiler Simulation Code
There are two programs here to generate water
properties. One is a Visual Basic program suitable for incorpotation
into an Excel spreadsheet. It has been used to model thermal heat
transfer between liquid sodium, a thin metal tube, compressed water or
superheated steam, another thin metal tube, an insulating materail,
pressure tube and finally a cooling water jacket in a shell type
counterflow heat exchanger. It has also been used to generate steam
tables and charts, and to do Steam Turbine thermodynamic analysis. This
program was originally downloaded from http://www.cheresources.com/iapwsif97.shtml
and is based on the model for water substance accepted by NIST, ASME
and IAPWS. It does not extend to
as high a pressure as the Fortran code but should be suitable for most
industrial applications. It is basically a derivation of the NBS
version which uses the Helmholtz function to determine thermodynamic
water properties over the entire region of temperature and pressure.
Instead, this program has transformed the Helmoltz Functions to use the
Gibss Energy Function everywhere except in region three where the
Helmholtz Function is still employed.
The second computer program is written in Fortran
and generates
property values of water in the gas, vapor and liquid phases for a
range
of temperatures and pressures within a useful range of 0 to 3000 MPa
and
from 260 to 2500 K.
This program was originally published in the 1984
N.B.S./N.R.C. Steam Tables by Lester Haar, John S. Gallagher and
George
S. Kell and is the progenetor of the ASME version. I have modified it
to produce tables and charts similar to those
published in the book, and will add further code later so that it will
run as
a multiprocessing subroutine in a network environment that can quickly
analyze design and process changes to optimize the efficiency and power
output during a dynamic turbine or boiler evaluation.
So far it has generated saturation tables,
compressed
water and superheated steam tables which appear reasonable. As the
authors
state though... this algorithm has a slight problem when analyzing
properties
very near to the critical point, and some of the values that I have
printed
out do not match even what the authors have published in the book.
These
values can be found at 647K +/- 1K, or at density values of 0.317g/cm^3
+/- 0.12g/cm^3. I don't believe however that the error is significant,
and can be easily worked around or corrected if needed.
<>Current: Fortran
Source
Code
Visual Basic Source Code
Tables
Charts
Excel Chart Spreadsheet