







			STEAM93/PC

		Properties of Steam and Water
		Interactive Desk Reference

		NBS/NRC IAPS'84 Formulations
		
	"The most accurate properties of water and steam in the world"





			By:
		Benjamin R. (Ray) Strong, Jr. and
		IMPULSE Engineering
		415 Arch Street
		San Francisco, CA 94132
			(415) 239-0940 Voice
			(415) 229-2354 Fax
		Internet:
			76260,1200@CIS.COM      (weekly)
			Thermo@hooked.net       (daily)
			ThermoRay@AOL.com       (weekly)




		Copyright 1984 through 1994
		Benjamin R. Strong, Jr. P.E.


License Agreement

This manual and software is protected by both United States 
Copyright law and international copyright treaty provisions.  

You are granted a 30 day trial license.  If you use the software 
for more that 30 days you MUST purchase a license to continue 
using the program.  One license is required for every copy of 
the program.  If the program will be used on a network, an 
additional license is required for each additional person who 
uses the program.

Your licenses registration is not extended to anyone else.  
You may not distribute your registration number and if your 
registration number is distributed, your license will be revoked.

This version of STEAM93/PC is shareware.  You may distribute 
this program to others for their evaluation.  Each additional 
copy you distribute is also bound to a 30 day trial period beginning 
from their receipt.

You may copy this software to your computer.  Also, to protect your 
investment from loss, you may make archival copies for the 
sole purpose of backing up the software.  


Network License

If more than one user will be allowed to use the software on 
a computer network at the same time, additional users need to 
be authorized by paying for an additional fee for each 
additional user.  By computer network, we mean any 
configuration of electronically linked computers where two or 
more users have access to the same computer program. 

Requirements, Transportability and Compatibility

STEAM93/PC will run on all IBM/PC's and compatibles with 356k 
of memory or above also running PC/MS-DOS 1.1 or above.  A 
graphics card and video monitor that supports IBM standard 
text is required.  An 80i87 NDP is strongly recommended: operation 
without an NDP may be excessively slow.

STEAM93/PC may not function properly in every hardware/-
software environment, particularly in modified versions of 
the operating system.  Graphics characters showing on the 
screen may not be displayable on all printers.

ACKNOWLEDGEMENTS
IBM (TM) of International Business Machines, Inc.
Microsoft (TM) of Microsoft, Inc.
1-2-3 (TM)  of Lotus Development Corporation.
Sidekick is a tradename of Borlund International.

GETTING STARTED

Check for Completeness

The program is found as part of the self-extract compressed file
STEAMDOS.exe.  (If you're reading this manual, you've likely 
already expended this file.)  Just execute it to uncompress the 
files.  The files in the package are:
	STEAM.EXE       The STEAM93/PC program
	DUMMY.DAT       A practice data set
	DUMMY.PRN       The practice data set for use by 1-2-3
	STEAMAN.TXT     This manual

Before running the program, make a copy (see your DOS manual) 
and use the copy for general use and practice session.

Notes on your System

STEAM93/PC will run on many different color or monochrome 
monitors with composite or RGB signals, and the Compaq and 
IBM portables.  It was written for MGA, CGA, EGA, Compaq, and 
compatible graphics cards.

STEAM93 has been tested in a variety of 8086/8088/80286 and 
high-speed CPU enhancements including ultra-high-speed co-
processor accelerator cards and machines.  However, the 
addition of an 80i87 to your system will make much more 
difference than a faster or newer CPU.

For best results, a color monitor is recommended: STEAM93 
uses color enhancements to increase the information content 
and for ease on the eyes.  If you have a Compaq with an 
external monitor, remember to turn it on using the Ctrl-Alt-< 
keys.

The program will run with or without a NDP chip, but runs 
much faster with it installed.  This especially applies to P-
h, P-s, and some transports calls which can be quite time 
consuming.  If you are using an 80i87, STEAM93 will use it 
extensively.  This can be used as a test of the 80i87 - if an 
inconsistency or program abort occurs during calculation, it 
is our experience that this is most likely an 80i87 problem: 
that the 80i87 is operating too "hot", or at too high a 
speed.  If you have a switchable system clock, try slowing the 
clock down.  If problems occur with a cold/slow system, call 
us immediately.

If the version of your program is copy protected, you will 
only be able to use the program on the diskette provided to 
you. We hope this doesn't provide too much of an 
inconvenience to you.  If you have damaged the diskette, 
please send it back and we'll send you a new one.

Post Processing the STEAM93 Properties Data

For follow-on calculations,  data logging, and/or plotting we 
suggest Lotus 1-2-3.  This spread sheet program can be used to 
automatically perform some quite complex calculations.  (More 
about 1-2-3 later.)

You can also use 1-2-3 to convert STEAM93/PC data for use by 
dBASE-II/III. For on-line calculations, we recommend 
Sidekick.


Table of Contents

Getting Started
	Check for Completeness
	Notes on your System
	Post Processing the STEAM93 Properties Data

Table of Contents
List of Figures
List of Tables

INTRODUCTION
	About Steam93/PC
	Related Products
	About IMPULSE Engineering

STEAM93/PC USAGE OVERVIEW
	Starting the Program
		Loading the Program
		Practice Session
		EXIT'ing, Ending your Session
	Screen Layout and Use
		Properties Screen
		Additional Transports Screen
		Messages and Indicators
	On-Line Helps
	Inputting and Deleting Data
		Inputting Property Data
		Inputting Property Combinations
		Copying Data
		Deleting Data
	F3 Key, Finding State Values
	Opps! = ESC and Recovery
	Calculation Options
		Critical Region Toggle
		Transport Calculation Toggle
		Printing
		Units

USING THE STEAM TABLES
	Finding Saturation Values
	Isentropic Searches and Efficiencies
	Availability

SAVING AND RETRIEVING YOUR SESSION DATA ON DISK
	Saving Your Session
	Saving To Your Default File
	Retrieving a Data File
	Merging Partial Data Sets

USING STEAM93 WITH LOTUS 1-2-3

ENGINEERING NOTES
	Critical Mass Flux
	Speed of Sound in the Two-Phase Region
	Thermodynamic Quality
	The Very-Near Critical Region
	Range, Physical Accuracy, and Consistency

REFERENCES

Appendix A  SERVICE AND WARRANTIES
	PRODUCT SERVICE
	LIMITED WARRANTY

Figures
	1.A Properties Screen Layout and Function
	1.B Additional Transports Screen Layout and Function
	2.A General Help Screen
	2.B Input Help Screen

Tables
	1 Thermodynamic and Transport Properties
	2 Range and Accuracy
	3 Units Conventions

INTRODUCTION

About STEAM93/PC

STEAM93/PC was written to provide the highest accuracy and 
highest consistency reference for the properties of steam and 
water available anywhere in a fast and  easy to use form.  
Much concern and time was spent to make sure that annoying 
problems such as data overflow, format overflow, system lock-
ups during difficult calculations,... will not occur, and 
protection against them is automatic.  Also, knowledge of the 
state range is not required.  Our goal is to make the process 
of using the program as comfortable, natural and 
unsophisticated as possible without burdening you with quirks 
of the solution techniques, system, machine, or programming 
languages.

STEAM93/PC provides the state and transport properties shown 
in Table 1 to the accuracy estimated in Table 2.  The 
exceptional accuracy is due to the following:

-- Each and every property calculation is evaluated from the 
fundamental formulations.  No approximations are introduced 
by using tables, interpolations, splines, curve fits, or other 
approximations.  

-- The fundamental state property solvers are the most accurate 
and most consistent formulation currently available anywhere.  
These are applicable over a much wider range than any other 
correlation [1, 3].  These solvers are based on the most recent 
internationally approved material from the International 
Association for the Properties of Steam.  The formulations, 
approved as the "IAPS Formulation 1984", were developed by the 
US National Bureau of Standards and the National Research 
Council of Canada and have also been approved by the American 
Society of Mechanical Engineers through their Research 
Committee on the Properties of Steam (as members of the 
IAPS).

In addition, the STEAM93/PC implementation has been written to 
take advantage of this correlation in some special ways:

	STEAM93/PC is verified to source data and independent 
	parallel correlations 
		to the greatest number of significant digits published 
		in all available reference works, and
		throughout the entire range of applicability.

	The Gibbs condition for phase equilibrium is used for 
	the calculation of saturation conditions and coexisting 
	phases.

	In the very-near critical region, where even mainframe 
	implementations have great difficulty, an optional 
	correlation is available to accurately resolve property 
	data.

	The range of applicability is extended to 100,000 Bars 
	and 100,000K.

	Full data precision is available to SAVE and spreadsheet files 
	for accurate post-processing with the property data, or 
	for data logging.

STEAM93/PC includes transport and indirect properties from approved 
standards commonly used in engineering applications.

To make STEAM93 more useful the general format is like a 
spread sheet for systems and component studies, with data 
copying, printable files for data logging, and other 
features.

The development of STEAM93 for the PC began with the basic 
formulations and embedded them in a fault-tolerant 
environment for greater accuracy and transportability.  This 
environment was then improved by use of the FORTRAN Addenda 
(also available from IMPULSE Engineering) which provides the 
screen, keyboard, and file management utilities.

STEAM93 has been used in a variety of applications areas, 
ranging from power systems studies, meteorology, aerospace, 
component design, and pre-processing for fluid systems 
simulation programs.  Please let us know of your application, 
and especially if you have questions or problems in using the 
program.

Related Products

IMPULSE Engineering has a number of products that can help you 
develop programs for science and engineering applications.  You 
can receive more information by writing, calling, or e-mailing 
us at the locations shown on the cover sheet.

    Verification Package for STEAM93
	This documentation describes the extensive verification and 
	benchmarking for STEAM93.  The document includes the plan, 
	results, and output files used.

    STEAM93.DLL 
	STEAM93.DLL allows MS-Windows developers and users of 
	applications such as MS-Access, Win-Basic, MS-Word and Excel 
	to access the NBS/NRC steam tables from within their 
	application.  Using MS-Windows Clipboard, OLE, and other 
	resource, the steam tables can now be imbedded in any Windows 
	application.

    STEAM93/Win
	This is a windows application that provides the same range of
	services as STEAM93/PC for DOS.  Written specifically for the MS-
	Windows environment, STEAM93/Win allows Clipboard and real-time 
	OLE connections to other applications and documents.

    STEAM93/PGM
	The STEAM93 correlations are available as FORTRAN subroutine 
	source code for custom applications on non-IBM compatible 
	platforms.  The package comes complete with a Programmer's 
	Reference manual, example source code, and structure charts and 
	diagrams.  A FORTRAN application front-end and benchmark data set 
	are also included.

    FORTRAN Toolkits
	The FORTRAN Toolkits are libraries of routines for developing 
	user friendly programs in the DOS & FORTRAN environment.  The 
	routines range from windowed graphics to string searches, from 
	on-screen editing control to file management.

    Engineering Libraries
	IMPULSE Engineering distributes libraries of engineering data.
	These can be called from Windows programs or applications that 
	access Windows dynamic Link Libraries (.DLLs).  These libraries
	include
		Geometry, properties, and schedules of pipes and tubes
		Pressure drops in piping and components
		Valve and damper characteristics
		Psychometric calculations for water and steam
		Steam tables (see STEAM93.DLL above)
	Each comes complete with documentation and sample programs.

About IMPULSE Engineering

IMPULSE Engineering provides specialized consulting and software 
services in thermodynamics and mechanical engineering to the 
aerospace, environmental, and energy industries.  Our mission 
is to provide or create the highest quality state-of-the-art 
technology to make our world a better place to live.


Table 1 Thermodynamic and Transport Properties

#   Property             Abbreviation    Description
	   (many of the standard symbols are unprintable)

1   Pressure               p, Press        p = T(s/v)u
2   Temperature            T, Temp         T = 1/(s/u)v
3   Specific Enthalpy      h, Enthal       h = u + pv
4   Quality                x, Qualty       (See Technical Notes)
5   Specific Volume        v, SpcVol       v = 1/r 

6   Availability           go, Avail       go = h - Tos
7   Specific Entropy       s, Entrop       s = -(A/T)v
8   Specific Internal 
     Energy                u, IntEng       u = A + Ts
9   Nozzle                 p/v             p/v
10  Specific Heat Capacity 
     at Constant Pressure  Cp              Cp = (u/T)v

11  Specific Heat Capacity 
     at Constant Volume    Cv              Cv = (h/T)p
12  Dynamic Viscosity                     IAPS'75
13  Conduction Heat 
    Transfer Coefficient   K, HtTran       IAPS'85
14  Speed of Sound         Cs, w,SndSpd    
15  Isothermal Bulk 
     Modulus               B|T, BulkM|T    BT = 1/k

16  Hemholtz Function      A, Hemhlz       A = u - Ts
17  Gibbs Function         g, Gibbs        g = h - Ts
18  Prandtl No.            Pr, Prandtl     Pr = Cp/K
19  Critical Mass Flux     W*/A*           W*/A*
20  Isentropic Exponent    -, Gamma        - = -v/p(p/v)s
					   - = 1/a p

21  Kinematic Viscosity    u ,KinVisc      u =v
22  Isobaric 
     Compressibility        , Comp|p       = (1/v)(v/T)p
23  Isentropic 
     Compressibility       _  , Comp|s     _ = -(1/v)(v/p)s
24  Isentropic 
     Bulk Modulus          B|s, BulkM|s    Bs = 1/a
25  Free Convection 
     Coefficient           nc, NatCon     nc = gb/u2 

26  Thermal Diffusivity    a, ThrDif       a = Kv/Cp
27  Surface Tension        s, SurfTn       IAPS'75
28  Static Dielectric 
     Constant              _, Dielec       IAPS'77
29  Isothermal 
     Compressibility       k, Comp|T       k = -(1/v)(/p)T
30  Compressibility Factor Z               Z = pv/RT

(1) Calculated directly from the IAPS'84 Hemholtz function 
and it's derivatives [1,3], not necessarily from the 
equation shown.  When an IAPS release date is shown, the 
formulation is from that IAPS specification.

(2) In the 2-phase region the critical velocity V* is 
substituted for Cs.

(3) Calculated assuming p, v, ... are TOTAL conditions.


Table 2 Range and Accuracy


PROPERTY              RANGE           ACCURACY (1)   / NOTES

Pressure      0 < p < 10,000 Bars    IAPS'84
	      p < 30,000 Bars        IAPS Extrapolations / (3)
	      p < 100,000 Bars       STEAM93 / (4)

Temperature   0.01 < T < 1,000C     IAPS'82 / (2)
	      T < 2,773             IAPS Extrapolations / (3)
	      T < 100,000C          STEAM93 / (4)

Specific 
Volume        0 < T < 600C,
  v(p,T)      0 < P < 500 Bars;
		Liquid                1 part in 10,000 (0.01%)
		Vapor                 1 part in 1,000 (0.1%)

		General:
	      T < 1,000C,
	      p < 10,000 Bars        10 parts in 10,000 (0.1%)

		Anomalous Region      2 parts in 100,000   0.002%)

		Metastable States     "... very good ..."

Vapor 
 Pressure     0.01 < T < Tcrit      12 parts in 100,000 (0.012%)

Specific Enthalpy of 
 Vaporization        "              2 parts in 10,000 (0.02%)

Specific 
Enthalpy      1 < p < 5,000 Bars    h(p,T) = p_h(1,T)
	      5 < p 5,000 Bars      h(p,T) = [5+2(p-5)]_h(1,T) 
						/ (5)

Specific Heat at Constant 
 Pressure     p < 1,000 Bars        Generally 1% 

Dynamic Viscosity 
 [2]          0 < T < 800C         Generally 1% / (6)
	      0 < p < 1,000 Bars 

		Useful Range:
	      T < 100C and p < 10,000 Bars
	      T < 560C and p < 3,500 Bars

Thermal Conductivity 
 [2]          0 < T < 800C           / (6)
	      0 < p < 1,000 Bars


Notes:

(1) Accuracy is taken from References [1] and [2]: 
conservative summary of high error estimates based on 
comparisons with test measurements.  Reference [1] has a 
very complete review of accuracy and should be consulted if 
range-specific accuracy information is required.

(2) International Practical Temperature Scale of 1968 (IPTS 
'68)

(3) Extrapolation of fundamental equation as agreed upon by 
the IAPS. [3]

(4) Convergent/Consistent/Reasonable upper limits of 
calculation with no accuracy estimates proposed or 
attempted.

(5) _h(1,T) is the uncertainty in dh at T and 1KBar.

(6) Within the uncertainty of the test measurements. [2]


STEAM93/PC USAGE OVERVIEW

The STEAM93 program is used like a spread-sheet program with 
fixed form and functions of the data.  The following sections 
will present an overview of the program's functions and 
usage. The easiest way to become familiar with the program is 
to load the sample session and just play with the options and 
capabilities.  Remember to use a copy of the program for 
this, and not the original diskette!

Starting The Program

Loading The Program

(1) "Boot" (start-up) your system (if not already on) and 
insert the STEAM93/PC diskette into the drive you want 
to use.

(2) Just as you normally would, use DOS to set the default 
disk to the drive where you put the program diskette e.g., 
if the program diskette is in drive B and the prompt on the 
display shows 
	A:>  
then type in B: and hit the carriage return key (Enter key).  
The DOS prompt should now show 
	B:>

(3) Type in STEAM and hit the Return key (Enter). After a 
few seconds, the screen will fill and a pair of square 
brackets, [ ], will appear to define a cell for input.
That's it.  From here on you're in STEAM93/PC.  For a Help 
screen, reminder for what keys control the program, hit F10.  
To print that page, turn on your printer and hit the PrtSc 
key.  Use this as your reference until you can 
remember how the special keys work.

Practice Session

For practice, read in the data file found on the diskette.  
To do this, hit the F6 key (this is the file read key) and 
type in the file name, dummy.dat.  Then hit *Enter and wait 
until the data reprints on the screen.  From here on, enter 
or delete data or practice with the various functions.

EXIT'ng Ending The Session

To exit back to DOS, just hit Ctrl+Home (hold down the Ctrl 
key and hit the Home key at the same time).  (It's a good 
idea to save your session first.)  If the data currently used 
by the program is not the same as the SAVE file, the program 
will ask you to verify if you want to exit without saving the 
current data.  This will give you an extra chance to SAVE 
your data.

Screen Layout And Use

The STEAM93/PC program uses four screens to express itself - 
two screens of data (shown in Figures 1.A and 1.B) and two 
Help screens (Figures 2.A and 2.B).  Use of the two data 
screens is similar for all of STEAM93/PC's capabilities as 
discussed in the following sections.

Properties Screen

When you start-up a session you'll see the screen shown on 
Figure 1.A.  This is the main screen for all water properties 
operations.  There are eight columns, labeled "Pt n", 
referring to State Points, for process studies.  To the right 
of the screen there are two columns for property names and 
units labels: these labels apply to each column and cell in 
the row.  The rows of properties for each of the 8 different 
State Points are totally independent "calculators".
Each of these spaces are called "cells", just like a spread 
sheet.  The cell you are working on is identified by the 
blinking (red) brackets.  Movement for data entry and such is 
done using the cursor controls on the keypad (to the right of 
the keyboard).

A second screen, shown in Figure 1.B contains additional 
transport data. This is accessed as discussed in a following 
section.

Some of the units have coefficients, or exponents with the units
name. This is intended to be read as a literal suffix to the
number showing in the cell: don't invert the sign, just assume
that it is a multiplier to the number showing.

Additional Transports Screen

In addition to the main screen of property and transport 
data, there is an additional page of data shown in Figure 
1.B. You can access this page by hitting PgDn on the keypad.
The data layout for this screen is the same as the properties 
screen discussed above.  You can use the cursor to move 
around this screen, and access most other program functions 
except number input and calculate.  When you are ready to 
return to state operations, just hit PgUp.

Messages and Indicators

While you are working with the screen, take special note of 
the top line.  You will see four words which indicate where 
you are and what to do (see the General Help screen or Figure 
2.A).  Mostly, keep track of the "Wait" indicator when it 
appears: the program is working on something until "Inactive 
Any Key" appears on the top line.   As you work more with the 
system you'll find these helpful in assuring that the program 
has done what you want.  Except for file I/O, you shouldn't 
have to wait long.

On the top line you'll also see an indicator for the cell 
location, as (n,y) where n is the state point number and y is 
an abbreviation for the state property.  When data for the 
property and state point is available, the number will also 
appear here. (If the number to 8 places doesn't immediately 
appear, move the cursor away from the cell and back to the 
cell. It should then appear.)

The time of day and the date are shown to the right of the 
screen on the top and bottom lines.  These are for your 
reference as you use the program and are also written to the 
print and save files for data logging or checking for the 
right file.

During the use of the program you will also notices changes 
in the intensity or the color in screen items.  More about 
these later.


Figure  1.A Properties Screen Layout and Function

STEAM`93(6,h)= .27245044E+04 Properties Operations  Inactive   any Key 15:37:24
----------------------S T A T E   P O I N T S   ( Water )---------------------
PROPERTY UNITS\ Pt 1    Pt 2    Pt 3    Pt 4    Pt 5    Pt 6    Pt 7    Pt 8
Press: Bars            100.000                 100.000 100.000
Temp:   C              311.031                 311.031 311.031
Enthal:KJ/Kg           1407.28                 2724.50[2724.50]     
Qualty:                 .0E+00                 1.00000 1.00000
SpcVol:m^3/Kg          .001452                 .018025 .018025  
Avail: KJ/Kg           489.733                 1191.05 1191.05
Entrop:KJ/Kg C         3.35912                 5.61395 5.61395
IntEng:KJ/Kg           1392.75                 2544.25 2544.25
Nozzle: p/v            68862.8                 5547.71 5547.71
PROPERTY UNITS\ Pt 1    Pt 2    Pt 3    Pt 4   Pt 5    Pt 6    Pt 7    Pt 8
 Cp:   KJ/Kg C         6.12439                 6.89730 6.89730
 Cv:   KJ/Kg C         3.05600                 2.99751 2.99751
DynVis:e-6Pa-s         81.8295                 20.2664 20.2664
HtTran:mW/m C          526.976                 76.3337 76.3337
SndSpd:m/sec           843.401                 474.303 474.303
Bulk|T:Bars            2444.25                 54.2385 54.2385
Hemhlz:KJ/Kg           -569.58                 -735.31 -735.31
Gibbs: KJ/Kg           -555.06                 -555.06 -555.06
PROPERTY UNITS\ Pt 1    Pt 2    Pt 3    Pt 4    Pt 5    Pt 6    Pt 7    Pt 8
KEYS     Soln:          Analy.                  Analy.  Analy.
AT       Regn:          SatLq                   SatVp   SatVp
F10=Help!, F1/F2=Copy, F3=Calc, ^F4=Calc.all, F5=Save, ^Home=Quit   11/ 6/1992  

Figure 1.B Additional Transports Screen Layout and Function


STEAM`93(6,P)= .18312173E+01 Transports Reference              any Key 15:41:49

PROPERTY UNITS\ Pt 1    Pt 2    Pt 3    Pt 4    Pt 5    Pt 6    Pt 7    Pt 8
Prandl:                 .95100                 1.83122[1.83122]
Wc/A:  kg/m^2s         108640.                 15491.1 15491.1
Exp|s:                 48.9840                 1.24803 1.24803
KinVis:mm^2/s          .118830                 .365312 .365312
Comp|P:1/ C            .003847                 .008263 .008263
Comp|S:1/Bars          .000204                 .008013 .008013
Bulk|S:Bars            4898.40                 124.803 124.803
NatCon:1/mm^3C         2671.60                 607.217 607.217
ThrDif:mm^2/s          .124952                 .199491 .199491
SurfTn:N/m             .011863                 .011863 .011863
Dielec:                18.7849                 1.33296 1.33296
Comp|T:1/Bars          .000409                 .018437 .018437
   Z:                  .053861                 .668573 .668573
PROPERTY UNITS\ Pt 1    Pt 2    Pt 3    Pt 4    Pt 5    Pt 6    Pt 7    Pt 8

--------------------------------------------------------------------------------
----------------------------- IMPULSE Engineering ------------------------------
----------------- STEAM`93/PC v3.1 (C) 1992 B.R.Strong,Jr.,PE. -----------------
--------------------------------------------------------------------------------
 PgUp to return to properties.                                                 
_


On-Line Helps

By hitting the F10 key, the program will switch to one of the 
Help screens.  During non-input operations, a Help screen 
that has memory "joggers" for the keys and special functions 
of the program will appear.  During input, a different Help 
is available which describes special input and editing keys.  
If you need more information than is on the two Help screens, 
please refer to this manual.

To return from Help to your prior operation, just hit any 
key.

Also note the bottom line during normal operation which has 
the most common keys, and is used for messages and prompts 
for file information.


Figure 2.A General Help Screen

STEAM`93/PC v3.1              Help     Reference   Inactive   any Key (time)
		      Mode of Operation---+                      
				    Operations Status--+          
						    User Prompt---+
		      STEAM9X NBS/NRC-IAPS`84 Steam Tables

KEY       RESULT / Function            KEY       RESULT / Function
				      
   F1     Copy cell into Xtemp.           Esc    Abort Process.
   F2     Copy Xtemp into cell.       
   F3     Find St.Pt. Properties.         Del    Delete data at this cell.
   F4     Find Props at ALL St.Pts      Alt+D    Delete ALL data for Pt.
   F5     Open File.                  
   F6     Save File.                     PgDn    Transports Screen 2.
   F7     Save File as ...               PgUp    Retn To States Screen 1
   F8     Print to 1-2-3.               Alt+T    Toggle Transport Calc.s
   F9     Change Units.                 Alt+C    Toggle Critical Region.
   F10    Help!.                       Ctl+Home  Return to DOS

Notes: [  ] denotes current cursor (cell) location; move it using the keypad.
	To input data, just type in the number and enter it with a return <CR>.
	When 2 properties are input, hit the F3 key to calculate the others.
	Use F1 and F2 (Xtemp I/O) for copying an entire cell.
	Note the UNITS and POWER (en) are a LITERAL SUFFIX to the cell value.
Next key is processed on return. Indicates data is different from SAVE file. -> 




Figure 2.B Input Help Screen

STEAM`93/PC v3.1              Help     Reference   Inactive   any Key 15:47:26
			  -------- INPUT HELP --------
      STEAM`92 input is similar to a line editor and DOS.  You enter data by
     just typing the data and hitting the <CR>. Like DOS, the prior data is
     stored in a buffer from which you can copy using F1 and/or F3. If you
     wish to edit the prior data, hit F3 and a line editing mode is active.
     This mode is also active when a syntax error is found. To exit without
     any modifications, the `opps` functions are provided. STEAM`92 will
     check your inputs STROKE by STROKE for context and syntax !
     KEY       FUNCTION
      Esc   Start over. If on col. 1, Esc an `opps`
     <CR>   Enter data. On a syntax error, the cursor ID`s the problem and
	    editing is turned on.  <CR> on col. 1, is `opps`.
      F1    Copy 1 char. from prior data (buffer).
      F3    Copy remaining data from prior data (buffer). Editing turned on.
     Del    Delete the character to the right. (Buffer moves to left.)
     BkSp   Delete the character to the left. (Buffer moves to left.)
     Ins    Insert a keystroke at the cursor location. (Buffer moves to right.)
   Ctrl+End Universal `opps`, available at any time.
	  Notes
   `opps`   Exit without any change of data or action.
    Edit    Editing is turned ON by F3 or a syntax error.
	    Editing is turned OFF by Esc.
   NumLock  Toggle to allow number input from the keypad. Cursor is turned OFF.
		     Any key to continue input.                                
_

Inputting and Deleting Data

Inputting Property Data

The input and editing is quite natural and follows DOS, 
EDLIN, and word processors. Unlike those, STEAM93 will check 
the context of the data.

To enter a number at the cell you're at (denoted by the 
brackets), just start to type a number.  A small cursor (_) 
will appear at the left of the bracketed space indicating to 
go ahead and type in your data.  (There will also be a prompt 
on the top line which indicates what type of input is being 
requested.)  Just type in the number in any real (with or 
without a decimal point) or exponential (e, d, g) format and 
enter it with a carriage return, *Enter.  Unlike most 
interactive programs, STEAM93 "buffers" your input data, 
checking the inputs character -by- character.  Almost 
anything will work and the usual rigid forms are relaxed 
here.

Data is entered with the usual carriage return key, *Enter. 
If the number is unacceptable for some reason, the editing 
mode is automatically turned on and the cursor is re-located 
to the offending digit as discussed in the following section.

After successful entry, the program will modify the 
appearance of your input to provide the maximum number of 
digits of accuracy.  This automatic formatting is for "looks" 
only - all of the information you input is stored in the 
computer, and will be echoed on the top line to 8 significant 
digits.

You can also use Sidekick to input data by moving to the 
location  where you wish to enter the number stored by 
Sidekick and hitting the key programmed to hold it.  Refer to 
your  Sidekick manual for such operations.

All successful inputs are identified on the screen by an 
inverse color or intensity.  If you find you cannot input 
data in a cell, it's because this property is not allowed as 
one of the two acceptable inputs available for finding 
property values.

The following sections describes the individual key 
protocols. It's not as confusing as it appears, and follows 
DOS or standard word processing protocols.


Normal Input

The standard input is as discussed above - just type in the 
numbers and hit *Enter. Additional keys, similar to DOS and 
EDLIN,  are available to help you with this:

Esc
'Opps'. When on data column 1: Esc 
is an 'opps', returning without 
change of any kind. When anywhere 
else, Esc restarts the input 
process.

F1
Character Copy. Like DOS and Edlin, 
this copies a single digit from the 
data shown prior to starting input.

F3
Dump Buffer Copy. Like DOS and 
Edlin, this copies the remaining 
digits from the prior data and 
turns on the editing mode (see 
following section).

Bksp
Delete Character. Deletes the digit 
to the left of the cursor

Ins
Insert On/Off. Toggles on/off the 
insert function. If Ins is ON, the 
next input digit is entered and the 
buffer (prior data) is shifted 
right.

Del
Delete Buffer Item. Shifts the 
buffer (prior data) left (like DOS)

F10
Help. The input Help screen. Any 
key is used to return from this 
screen.

*Enter
Enter Data.  If there is an error, 
the cursor will move to the source 
of the error and editing is turned 
on.


Editing Mode (F3 During Input or Input Error)
If F3 is hit (or if the *<Enter would not allow the data), 
the full editing is turned on and additional editing 
capabilities are available:

Esc
Restart. Restarts input and returns 
to non-editing (normal) input mode. 
A second Esc is an 'opps', restoring 
the screen and data.

Bksp
Delete Single Item. Deletes the 
digit to the left of the cursor (_) 
and closes up the data to the right.

Del
Delete Single Item. Deletes the 
digit over the cursor (_) and closes 
up the data to the right.

Ins
Insert On/Off. Toggles On/Off the 
Ins mode. If Ins is on, the next key 
struck is inserted above the cursor 
and the data is moved right to make 
room for it.

*
Right. Just moves the cursor (_) 
right. Ins mode is turned off.

*
Left. Just moves the cursor (_) 
left. Ins mode is turned off.

Home
Flush Left. Cursor is moved to 
column 1. Ins mode turned off.

End
Flush Right. Cursor is moved to the 
last significant (non-blank) digit. 
Ins mode turned off.

Editing After an Error

If the bell sounds after hitting *Enter to enter data, the 
number is unacceptable and the editing mode is automatically 
turned on.  The cursor moves to the location of the offending 
digit or symbol, and you can edit just like a data string as 
discussed in the prior (F3) section.

Editing the Previous Data

To edit data showing on the screen, first hit a number to get 
into the input mode and then hit Esc once to get you back to 
column 1.  Then hit F3 to re-print the previous data and turn 
on the editing mode.  Once the editing mode is on, edit the 
data using the cursor and keys as discussed in the prior (F3) 
sections.

Input Property Combinations
You need not overly concern yourself too much with the valid 
input combinations allowed; STEAM93 checks them 
automatically.  For your reference, they are:

p and T
Pressure and temperature

p and h
Pressure and enthalpy

p and x
Pressure and quality

p and v
Pressure and specific volume

p and s
Pressure and entropy

T and x
Temperature and quality

T and v
Temperature and specific volume

Don't bother to memorize these, as the program allows only 
the acceptable combinations.

Copying Data

The F1 and F2 keys are used to copy data.  Hitting F1 will 
store the number at the current cell (within the brackets) to 
internal storage.  Hitting the F2 key will copy the number 
currently stored to the current cell. So, for repeating a 
number, enter the number in a cell, hit F1, move the cursor 
to the new locations, and hit F2.

The number stored is the full 64-bit accuracy allowed by the 
machine, even though all of the significant digits may not 
appear.  Output values provided from the program are to the 
full machine accuracy, so for consistency it is always better 
to reproduce a number using the F1 F2 sequence than to re-
input it by hand.  Full state consistency can be assured this 
way without being limited to the accuracy of your inputs 
digits.

Note that the copying process is units dependent, so that 
copying vertically to another data type will likely yield a 
different magnitude.  So copying data is best for horizontal 
copying between state points.

Deleting Data

Just hit the "Del" key on the keypad to delete the data shown 
at the cursor.  If additional data is deleted it's because 
you may have deleted data which was one of your previous 
inputs.  This is intentional for consistency.
To delete an entire column (State Point) of data use Alt+D 
(hold down the "Alt" key and hit the "D" key).

F3 Key, Finding State Values

When any two primary state variables (i.e., p and T or others 
identified in Section 3.5.2) are available for a state point, 
just hit the F3 key.  The inputs will be checked in context 
and the search for the other consistent state and transport 
properties.  You need not concern yourself with the range or 
state region of your inputs,

STEAM93 is smart enough to manage it alone and tell you what 
region your input / output is in.  If the inputs are out of 
range, a message will appear on the lowest line echoing the 
property at fault.  (This checking includes some pre-
calculation in certain regions so it may take a second.)  

Simply reinput the number and use F3 again.
While calculation is proceeding the messages on the top line 
will often change and the clock will continue to run.  
Calculation continues until the screen has reprinted the data 
for the state point and the "Inactive" message appears on the 
top line.

Some calculations, notably p-s and p-h calls, take quite a 
bit time.  As long as the clock changes time every few 
seconds or so, the program is still trying to find the 
consistent state values.  If you do not have an 80i87 
installed in your machine, please be patient, and wait for 
the "Inactive" message to appear on the top line.
If you wish to abort calculation before completion, hit the 
Esc key.

OPPS! = ESC and Recovery
The Esc key is used to end the current operation of the 
program.  During input of a number or filename, hitting Esc 
will end input, and restore the original data.
During calculation of a state point, hitting the Esc key will 
abort the calculation and return you to normal operation.


Calculation Options

There are two toggles you can use to reset calculation 
options of STEAM93 and control the handling of the very-near 
critical region and the calculation of transport properties:

Critical Region Toggle

In the very-near critical region, STEAM93 has an optional 
calculation method to evaluate properties and transports.  
When you start the program, this toggle is "off" as denoted 
by the letter "A" (for Analytic) appearing under the "Keys" 
note near the bottom-left of the screen.  In this default mode, 
the canonical fundamental equation (IAPS'84) is used throughout 
the calculations.

To access the alternative critical region method, hit Alt+C 
(hold down the Alt key and hit the C key).  This toggle is 
noted on the screen as a "C" (for Critical) instead of the 
"A".  This critical region formulation and correlations will 
be substituted for the IAPS'84 formulation whenever the state 
point is found to be in the very-near critical region.  (More 
about the this region and how it is defined and handled in a 
later section.)  To turn off this critical region detail, just 
hit the Alt+C key combination again.

Transport Calculation Toggle

If you have no need of the transport properties or specific 
heats, you can turn off their calculation.  When you start 
the program, this toggle is "on" as denoted by the letter "T" 
appearing under the "Keys" note near the bottom-left of the 
screen.  In this mode, the transport properties are 
automatically calculated.

To turn off automatic transport property calculation, hit 
Alt+T (hold down the Alt key and hit the T key).  Calculation 
of the transports will then be skipped, as denoted by a "N" 
in place of the "T". To calculate the transports, you need 
only to reset the toggle by repeating the Alt+T combination.
Note that if you have an 80i87 installed in you PC that the 
transport calculations do not take much time compared to 
state point calculations. Most of the time is spent printing 
to the screen rather than in calculation.

Printing

You can print out the screen at any time by using the shift-
PrtSc key (upper case and PrtSc keys at the same time) as 
provided by your operating system.  The files written by 
STEAM93 are also printable using the DOS "TYPE" command, but 
the output will not be as readable.
The DOS PrtSc command takes precedence over any STEAM93 
operation so the program will pause until the printing has 
finished.  Make sure your printer or spooler is on or DOS 
will wait forever for the printer to be available.

Units

Units are summarized in Table 3 with the abbreviations 
appearing on the screen.  Common units and abbreviations are 
used and should be self-explanatory.

For a few properties, notably the viscosity, there is an 
exponent ( e-6 ) preceding the unit. This, and the unit, are 
to be interpreted as a literal suffix to the number. As you 
would expect, if the data itself has an exponent (i.e., e-9), 
the exponents in the number and in the dimension are added 
(in this example, summing to e-15).

To switch back and forth from SAI to English/Engineering 
units, just hit F9.  All conversions are automatic.  
Conversion factors all use 8 significant digits and are 
consistent with ANSI/NBS Standards.


USING THE STEAM TABLES

As well as an accurate  reference for properties and 
transports at state points, STEAM93/PC offers a variety of 
convenient calculations capabilities.  A few of these are 
described in the following sections.

Finding Saturation Values

As you might expect, data right on the saturation lines is 
found using pressure and quality (p and x) or temperature and 
quality (T and x) as inputs.  Quality is input as either 0 
for saturated liquid or 1 for saturated steam.  (Also see 
Sections 8.1 and 8.3 for additional information.)

Isentropic Searches and Efficiencies

One of the most common uses of the steam tables is for 
observing isentropic processes and using efficiencies.  Using 
STEAM93/PC, this process takes just a few seconds.

For example, take an isentropic expansion process from 
StPt's (state points) (1) to (2) resulting from a nozzle or 
turbine.  In this example p1 and T1 are known.  First, p1 and 
T1 are input, and the F3 key is struck to calculate the 
remaining data for StPt (1).  Then s1 is copied to s2 at StPt 
(2) (using the F1 key at s1 and F2 key at s2).  The new 
pressure is entered at p2 and the F3 key is struck to 
calculate the remaining data at StPt (2).  The resulting data 
at StPt (2) are the properties and transports at (2) from the 
isentropic expansion.  This process can be rep-resented by:

s1(p1,T1)
s2=s1
y2(p2,s1)

where y2(p2,s1) is any property at StPt (2).

For an imperfect expansion process as for a turbine, an 
efficiency et, may be available for the process to discover 
data at p2 using StPt (3).  For the expansion, this 
efficiency may be described as:

et = (h1 - h3) / (h1 - h2)

To find data for the inefficient expansion process (1) to (3), 
StPt's 1 and 2 are created as in the above.  Then h3 is 
calculated using Sidekick or another calculator from:

h3 = h1 - et( h1 - h2 )

and h3 is entered at StPt (3).  p3 is copied from p2 (again 
using F1 and F2), and F3 used to calculate data at the StPt 
(3) for the inefficient process.

Note that critical mass flux (assuming pn and vn are at total 
conditions) and critical velocity (assuming pn and vn are at 
local static conditions) are available to assist in sizing 
and flow calculations.  Using the F1 and F2 copy sequence is 
recommended because the full 15 significant digits are copied 
and used for the calculation at the new state point - 
manually input will yield only 5 places or so of input 
accuracy and inconsistencies may appear.
For a compression process like a pump, the sequence of 
solution is similar. The isentropic process (1) to (2) is
resolved as for the compression process.  h3 is then found
from the pump efficiency:

ep = (h2 - h1) / (h3 - h1)
h3 = h1 + (h2 - h1) / ep

and entered for StPt (3).  p3 is copied from p2 and the new 
StPt (3) is found using the F3 key for the imperfect 
compression process.

Of course, the analogous process can be used for any constant 
property process: isobaric, isochoric (constant density), 
isothermal,...


Availability
The (steady-flow) availability function is provided for the 
evaluation of equipment and processes.  The availability 
function is defined as:

	go = h - Tos

where:
	go = steady-flow availability function
	h  = enthalpy

	To = environment absolute temperature (heat sink)
	   = 273.15C, is chosen for evaluation.
	s  = entropy

To evaluate the maximum work output for a reversible process 
between two states the difference in availability is used as:

	Specific Power = Power out / Mass Flow Rate
	Specific Power <=  go1 - go2

The difference between the maximum possible useful work 
output and the actual work output is sometimes called the 
irreversibility of the process.  By evaluating the 
availability and irreversibility, the primary sources of 
expensive energy waste can be identified and corrected.  The 
irreversibility can be used as a measure of the gains 
achieved in improving performance.

SAVING AND RETRIEVING YOUR SESSION DATA ON DISK

The protocol for file names in DOS is so flexible as to give 
most programs problems.  The protocol includes the disk drive 
(d:), the file name (filename), and an optional  extension 
(.ext) put together as d:filename.ext. If the file you want 
is on your default disk (identified by the d>_  or d: prompt 
before you executed the program), then the disk drive need 
not be entered, resulting in filename.ext.

As you may know from using other programs, DOS takes control 
on file name errors (illegal characters) or requests to disk 
drives which are unavailable (i.e., the door on the disk 
drive is open).  This usually disrupts program execution and 
results in unrecoverable aborts.

STEAM93/PC uses a number of protection devices to avoid most 
of these problems: filename inputs are checked for legal 
characters, the disk directories or local drives are checked 
to make sure the file is present (on reads), the drive name 
input is checked for legality,...  This is to make sure that 
you can always save your session.

When you hit a key signaling for file I/O, a prompting 
message will appear on the bottom line.  For the entry, upper 
or lower case does not matter.

Extensions (using a .ext at the end of the file name) are 
recommended.  For data (save) files use an extension of .DAT, 
and the 1-2-3 output file uses .PRN (Lotus REQUIRES an 
extension of .PRN).

Saving Your Session

To save your data, just hit F5.  On the bottom line a message 
and prompt will appear for you to type in the file name.  
Type it in and hit return.  If you hit the key accidentally, 
use the Esc key to recover.

The "Prompt" message on the top line will change after the 
read or write has been accomplished and reprinting of any new 
data is finished.  

Saving To Your Default File

If you're saving to the same data file more than once, use 
the F8 key.  If you've typed in a save file name once it is 
stored in the buffer and can be used any time later for the 
default.

Data in the save file is in the STEAM93 SAI units set in 
printable ASCII form with time and date of creation suitable 
for archiving.

Retrieving a Data File

To retrieve a session, use the F6 key.  You will be prompted 
for the file name as discussed above.

Merging Partial Data Sets

State points without data are not written to the SAVE file, 
and will not be reproduced / reprinted to the screen and not 
over-write data appearing for that state point.  You can use 
this to merge SAVE files from different data sets.

USING STEAM93 WITH Spreadsheets

To write the property data to a file compatible with 1-2-3, 
just hit F7.  The resulting file format is readable by Excel and
Quatro Pro and other spreadsheets.  As in the other functions 
to save and retrieve your session, a file name prompt appears on 
the bottom line.  Make sure that you use a file name extension of 
.PRN for 1-2-3.  When you are in 1-2-3, locate the cursor where 
you want the upper left hand corner of the STEAM93 data set to 
appear.  Then use the /File Import Number (/FIN) selections from 
the 1-2-3 menu to access and enter the data file.  Make sure to 
locate the 1-2-3 cursor at a new point so that it doesn't 
overwrite existing data: 35 rows by 10 columns should be 
anticipated.

The .PRN file written for 1-2-3 use includes headers and 
dates as well as the complete number data set.
The full accuracy of the data is stored in 1-2-3 even if it's 
not printed.  If you wish to show more digits of data, use 
the 1-2-3 display commands (/WG, etc.).


ENGINEERING NOTES
Critical Mass Flux
The critical mass flux is calculated by assuming the input 
intensive state properties are providing TOTAL (stagnation) 
conditions.  This is the only property provided in this way: 
all others assume input intensive properties are at local 
static conditions.

Speed of Sound in the Two-Phase Region

In the two-phase region the speed of sound is undefined.  In 
this region the critical velocity V*, calculated for 
isentropic process and equilibrium conditions, is substituted 
for the speed of sound.

Thermodynamic Quality

The thermodynamic quality, or vapor mass fraction, is 
generally calculated using  specific volume.  However, for p 
- h or p - s inputs in the saturated region enthalpy and 
entropy fractions are used instead as:

	p - h
	x = (h-hf) / (hg-hf)

	p - s
	x = (s-sf) / (sg-sf)

	other
	x = (v-vf) / (vg-vf)

When a state search results in subcooled values, x will be 
retained at 0.  Similarly, x for superheated vapor results 
will be set to 1.  In the supercritical region, x may be 0 or 
1.  The "Region" note for the state point near the bottom of 
the screen will advise you of the region.

Natural Convection Heat Transfer Coefficient
	
This term is a portion of the nondimensional Grashof Number 
used for free convection heat transfer studies. The full term is:

	Gr = BETAnc * ( L**3 ) * ( T - Tinf )
   where
	BETAnc = the term provided by STEAM'92
	     L = the dimensional length
	     T = the local fluid or body surface temperature
	  Tinf = the ambient fluid temperature

These terms are dimensioned such that Gr is nondimensional.
Where T - Tinf is large, it is recommended that this term
(as well as the Nusselt number) be evaluated at (T+Tinf)/2.

Units Coefficient

Some of the units have coefficients, or exponents with the units
name. This is intended to be read as a literal suffix to the
number showing in the cell: don't invert the sign, just assume
that it is a multiplier to the number showing.

Cv and Alpha:

The current release has incorporated new solvers for Cv and alpha 
(isentropic compressibility), in the 2-phase region.  These solvers 
circumnavigate the calculational problems as well as accurate results.

The Very-Near Critical Region

Accurate and unconditionally consistent resolution of 
properties in the critical region is a major strength of the 
STEAM93/PC and /PGM implementations and has previously been a 
long standing problem even in main frame programs.   For 
research purposes in the very near critical region an 
alternative, "Scaled Fundamental" formulation is provided.  
The analytic (IAPS'84) formulations are recommended and the 
default option.

The region very-near the critical point is very difficult to 
evaluate by any general purpose formulation even on mainframe 
computers.  The difficulty of calculation in this region is 
largely due to the flatness of Zq/ZT within a degree or so of 
the critical temperature.

For the IAPS'84 analytic formulation, 
"It should be noted that state of the art measurements 
for this region are consistent only to within ...

	p/p = (2x10-4)
	g/g = (2x10-5)

... for the region ...

	200 < p < 280 Bars
	160 < q < 450 kg/m3   "

(liberally paraphrased from [1])
As an option to using the IAPS'84 Formulation in this 
difficult to evaluate region, an alternative is available 
which uses the scaled fundamental equation recently 
recommended by members or the NBS and presented to the IAPS. 
"... the scaled fundamental equation is recommended in 
cases where it is important that the surface, and in 
particular its derivatives, display the physical 
behavior predicted by the modern theory of critical 
phenomena." [3]

This scaled fundamental formulation is valid in the region:

	644 < T < 693 K
	200 < q < 420 kg/m3

This formulation is quite fast and provides a level of 
consistency difficult to achieve with the general fundamental 
equation.

To remove potential inconsistencies in very-near critical 
two-phase and vapor applications the range of application of 
the scaled fundamental is adjusted upward slightly to:

	645.37 < T < 693 K

When the toggle is on for use of the equation (Alt+C has been 
hit and the "C" Key note is showing), the solution manager 
will check to see if the analytic result is in the applicable 
range for use.  If it is within range, the scaled fundamental 
equation will be used to calculate all state and property 
values.  When this formulation has been used, the Regn: note 
(for the state point near the bottom of the screen) will show 
"Criticl".

Be careful when you are working immediately on/near the 
limits of the range of the scaled fundamental formulation. 
There has been no attempt to remove the discontinuity in data 
and derivatives at the boundary of the range.  All values of 
the data are, of course, within the specified physical 
accuracy and consistency.  However, the relative error change 
across the border of applicability can appear large.


Range, Physical Accuracy, and Consistency

STEAM93/PC was designed to provide the most accurate and 
consistent properties of steam available.  STEAM93/PC has 
been benchmarked to be identical in all significant digits 
over the range of published data and tests or seven 
significant digits, whichever is MORE accurate.  NO 
approximations have been introduced in the implementation of 
the IAPS'84 formulations.  

Table 2 is an overview of the stated accuracy and range of 
the IAPS Formulation 1984 and transport formulations.  It is 
most significant that these are summaries of the comparisons 
with the physical data and not calculational accuracy.  
STEAM93 has been verified to all published significant digits 
throughout the ranges of the published data for these 
formulations.

The differences found in real applications occur with 
comparisons with earlier less physically accurate 
formulations.  A detailed analysis of the physical accuracy 
and comparison with other correlations can be found in 
References [1] and [4].

STEAM93/PC and /PGM were written for process studies as well 
as a standard properties reference.  Therefore there is a 
heavy emphasis on consistency as well as very high accuracy.  
This consistency extends throughout the calculational range 
of the program and the through the discontinuities.  You can 
test this consistency by inputting data for a state point 
using output data from another point.  You should find, as we 
have, consistency to twelve significant digits.

As changes to the industry standards are published (including 
the recent NBS publications), these will be incorporated if 
necessary.  You will be advised of the new release and if 
changes have resulted which might change the accuracy or 
reliably of the STEAM93/PC property data.


REFERENCES

1. L.Haar, J.S.Gallagher, & G.S.Kell, "NBS/NRC Steam 
Tables", Hemisphere Publishing Co., N.Y., 1984.

2. C.A.Meyer, R.B.McClintock, G.J.Silvestri, R.C.Spencer, 
"ASME Steam Tables", 5th Ed., ASME, N.Y., 1983.

3. J.Kestin, J.V.Sengers, B.Kamgar-Parsi, J.M.H.Levalt 
Sengers, "Thermophysical Properties of Fluid H2O", Amer. 
Chem. Soc., J. Phys. Chem. Ref. Data, Vol. 13, No. 1, 
1984, (Reprint 242)

4. J.M.H.Levalt Sengers,  B.Kamgar-Parsi, F.W.Balfours, 
J.V.Sengers, "Thermodynamic Properties of Steam in the 
Critical Region", Amer. Chem. Soc., J. Phys. Chem. Ref. 
Data, Vol. 12, No. 1, 1983, (Reprint 214)

5. W.C.Reynolds, "Thermodynamics", 2nd Ed., McGraw-Hill, 
N.Y., 1968. (Chpt. 8)

6. R.C.Reid, J.M.Prausnitz, T.K.Sherwood, "The Properties of 
Gases & Liquids", 3rd Ed., McGraw-Hill, N.Y., 1977.

7. Hendricks, R.C., Peller, I.C., and Baron, A.K., "WASP - A 
Flexible Fortran IV Computer Code for Calculating Water 
and Steam Properties", NASA-TN-7391, 11/1973.

8. T.Baumeister, E.A.Avallone, T.Baumeister III, "Mark's 
Standard Handbook for Mechanical Engineers", 8th Ed., 
McGraw-Hill, N.Y., 1978.


APPENDIX A  SERVICE AND WARRANTIES

PRODUCT SERVICE

The program is supported by:

	IMPULSE Engineering
	B. R. Strong, Jr., P.E.
	415 Arch Street
	San Francisco, California 94132
	(415) 239-0940 Office
	(415) 229-2354 Fax
	Internet: Thermo@hooked.net     (daily)
	Internet: ThermoRay@AOL.com     (weekly)
	Internet: 76260,1200@CIS.COM    (weekly)

New versions of this program, incorporating new features and 
capabilities, are regularly introduced as part of our new 
product development program.  We will notify registered users 
whenever a new release is introduced.  You have the option to 
purchase the new release or upgrade the version at a discount.
This product has a limited warranty for 3 months from 
purchase or receipt.  

Please let us know if you have problems or wish a special 
configuration of the program.


LIMITED WARRANTY

IMPULSE Engineering warrants that:

The program(s) and manual are complete and properly recorded;

The User's Manual is substantially complete and 
contains all the information which is deemed 
necessary for use of the program(s);

The program(s) functions substantially as described 
in the Manual;

This limited warranty is for 3 months from purchaser's 
receipt of the software and is extended only to the original 
purchaser of the software. 

IMPULSE Engineering excludes any and all implied warranties, 
including warranties of merchantability and fitness for a 
particular purpose and limits the end-user's remedy to return 
of the software and User's Manual to the address above for 
replacement.

IMPULSE Engineering specifically disclaims any other warranties, expressed or implied.  In no event shall B.R.Strong,Jr. or 
IMPULSE Engineering be liable for any loss of profit or any other commercial damage, including but not limited to special, 
incidental, consequential, or other damages.

Governing Law
This warranty statement shall be interpreted, construed and 
governed by the laws of the State of California.

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