Environmental Systems Engineering

218 Pages·1998·8.575 MB·English

by  Henry R. Bungay (auth.)

ENVIRONMENTAL
SYSTEMS
ENGINEERING
ENVIRONMENTAL
SYSTEMS
ENGlNEERING
by
Henry R. Bungay
Rensselaer Polytechnic Institute
Troy, New York U. S.A.
~.
"
SPRINGER SCIENCE+BUSINESS MEDIA, LLC
ISBN 978-1-4613-7516-6 ISBN 978-1-4615-5507-0 (eBook)
DOI 10.1007/978-1-4615-5507-0
Library or Congress Cataloging-in-Poblication Data
A C.I.P. Catalogue record for this book is available
from the Ubrary of Congress.
Copyright $1998 by Springer Science+Busmess Media New York
Originally published by Kluwer Academic Publishers in 1998
Softcover reprint ofthe hardcover Ist edition 1998
All rights reserved. No part of this publication may be reproduced, stored in
a retrieval system or transmitted in any form or by any means, mechanical,
photo-copying. recording. or otherwise. without the prior written permission of
the publisher. Springer Science+Business Media, LLC.
Printed an acid-free pap er.
TABLE OFCONTENTS
PREFACE ix
1. INTRODUCTION 1
Systemsengineering 2
Biologicalconcepts 4
Programmingforsystemsapplications 5
Oldreliablelanguages 5
Newerlanguages 6
Equationsolvers 7
2. SIMULATION 9
SIMBAS,SIMulationinBASic 11
Guideforwritingsimbasprograms 16
Dissolvedoxygensagcurve 21
Trickswithsimbas 25
3. PROCESS DYNAMICS 35
Dynamicanalysis 36
Forcingfunctions 38
Controllers 41
Distance-velocitylag 42
Templatesforgraphicaldesignoranalysis 45
Stability 50
Linearity 53
Open-andclosed-loopresponses 54
Bodediagramsinmatlab 55
Feedforwardcontrol 57
Programsfordynamicanalysis 57
4. DATABASES 61
Databasemanagement. 61
v
Spreadsheets 63
Electronicdatabases 77
5. COMPUTER MODELS 83
Philosophy 83
Curvefitting 84
Growth-raterelationships 88
Clemsonmodelofactivatedsludge 92
Partialdifferentialequations 93
Plumemodelsforairpollution 100
Estuarinecontaminantsimulator 102
Fugacityapproach 103
Observers 104
Cellularautomatamodels 105
Conclusions 106
6. HYDRAULICNETWORKS 109
Networkprinciples 109
Pipenetworks 110
Morecomplicatednetworks 118
Softwareforprocesses 118
7. NEURALNETWORKS 121
Howmanyboxesandhiddenlayers? 122
Neuralalgorithms 124
Commercialshellsforneuralnetworks 125
Discussion , 133
Bioprocessmonitoringandcontrol... 133
Publicdomainprograms 134
vi
8. EXPERTSySTEMS 139
Commonexpertsystems 141
Advancedfeaturesofexpertsystems 144
Commercialprogramsforexpertsystems 145
Applications 149
9. FUZZYLOGIC 155
Fuzzyoperations 155
Fuzzytruth 158
Fuzzycontrollers 162
Fuzzyapproachestostateestimation 170
Alittlemoretheory 171
10. STATISTICALAPPROACHES 173
Definitions 174
Distributions 175
Processperformance 180
Statisticalfeaturesofspreadsheets 184
Timeseriesanalysis 186
Extremevalueproblems 188
Independentvariables 190
Optimization 190
APPENDICES
A. RUNNING DOS PROGRAMS 193
B. INTRODUCTIONTOASPREADSHEET.. 197
C. MATLABPIPENETWORKPROGRAM 201
vii
PREFACE
Systems engineering is a key for advances in process analysis, development,
improvement, and control. While the principles of mass and energy balances,
kinetics, thermodynamics, and sciences are absolutely essential for sound
engineering,theyareanentryintonewermethodsthatalsomustbeintherepertoire
ofmodemengineers. This bookorganizes material used at Rensselaer Polytechnic
Institute in a introductory course environmental systems engineering that has been
taught for several years. Initially aimed at environmental engineers, its scope has
been broadened to include more chemical engineering. Each ofthe topics is often
treated byitselfin books orseparatecourses, socoverage here is greatly restricted.
Nevertheless,eachtopic isexplained with problemsand computerprogramssothat
practicalapplicationsarepossible. There isalways thedangerofmisuse becauseof
incomplete understanding, and further study beyond this book is highly
recommended.
The teaching of environmental systems engineering at Rensselaer Polytechnic
Institute is changing because of the World Wide Web (web). The computerized
tutorials written in BASIC that have been effective in the past seem ancient to
students who have grown up playing computer games with exceptionally fine
graphics. As time permits,ourcomputerexercises are being translated to Javaand
JavaScriptas interactivehypertextpresentationonthe web. Our goal is to makeas
muchuseaspossibleofthefollowing featuresofHypertext:
*Ahome pagereachedeasilyfrom the otherpages helps the reader to get backon
trackwhenlostinthenooksandcranniesofthepresentation.
* Study guides package web presentations into logical sequences and group
materialsforeachassignment. Eachguideisaspecializedhomepage.
ix
x Preface
*Citationsare"hotwords," andamouseclickinvokesexactlythatreference.
*Layered presentationsofequationsprovide bothacursoryand detailedderivation
andagrosslyoversimplifiedtreatmentforanyone withweakmath.
* Each assay procedure has an index page with entries for the techniques
themselves, evaluations and tips lifted from Ph.D. or M.S. theses, lists of
equipment,and namesofvendors.
* A glossary is accessed by key words on various pages and take the reader to
exactlythatentryintheglossary.
Linkstootherpagescanmaintainthe logicalthreadorcan branch. Forexample,an
introductory page links to moreadvanced material, and these more advanced pages
have hot words that bring up pages with explanations. The glossary and the
literature citations need no links because the Back feature ofthe browser software
puts you right back where you were. This is more sensible than scrolling to find
yourplacewhenanaddressinvokesthetopofthepage.
The number offiles on the web that relate to environmentlil engineering increases
daily, and any documentabout them is soon out ofdate. However, our home page
on the web is updated frequently. It has links to other archives throughout the
world. The starting page has the Internet address http://www.rpi.edu/dept/chem
eng!hypertext.html
During this transition period when not everyone has access to the web, this book
retains the tutorial exercises that have been superseded by the web exercises.
Computersnotconnectedtothe webcanstill installthe browsersoftwareand direct
it to files on a disk. Working from a disk avoids Internet delays and usually has
much faster response. Youcan have a friend with Internetaccessdownload files to
adisk for you, or you can requestdisks from the authorat H. Bungay, Department
ofChemical Engineering, Rensselaer Polytechnic Institute, Troy, NY 12180-3590.
When moved to the harddrive ofa personalcomputerthat hasa web browser, files
from the web pop into your browser almost instantly. The software for Internet
browsers has versions for Windows, Macintosh, Unix, Commodore Amiga, and
otheroperatingsystems. Publicdomain versionsare widelyavailable from Internet
archives, and there are commercial browsers. While it is not difficult to find and
install the public domain browser software, the commercial software has better
instructions. This book offers no advice about installation because most students
will use the system at their institution and only a few will need to configure their
personalcomputers.
Except for the hypertext presentations for any computer that has the web browser
software, most of the programs that you can download from our archive are for
MSIDOS because they will also execute in newer operating systems. Modem
operatingsystemsoffermorespeed, windows,and convenience, butworking within
the limitationsofMSIDOS does not impair presentation ofthe concepts covered in
EnvironmentalSystemsEngineering xi
thebook. The programscomefromavarietyofsourcesand are writtenindifferent
languages. Some public domain programs and some templates for commercial or
proprietaryprogramsareinourarchivefordownloading. Whileitis notpracticalto
distribute computer materials not in the public domain, sources are described in
sufficient detail that the reader should have no difficulty in ordering them.
Wheneverpossible, theassignmentsinthisbookarenotspecificto onecommercial
program, but the solutions are shown for one designated program. Most of the
source files are in ASCII format that should be accepted readily by otheroperating
systems. Authorsofthe programsarecredited within the programs themselves and
notinthisbook.
NEWANDUPDATEDPROGRAMS
Anyone on the Internet that connects universities, government laboratories, and
many commercial organizations can use e-mail to get help with the programs or
suggest improvements by contacting [email protected]. Our web archive has the
latest versions of the programs in compressed groups for downloading. Our RPI.
archive for FrP is no longer tended regularly because of our preoccupation with
browsersoftwarefortheweb.
Downloadingwitha webbrowser
While viewing a page with your browser, simply pull down the File menu to click
on SaveAs. Arequester will appearfor youto type in where you wish tosavethe
file thatproducedthispage.
Linksto files for downloading will also invokea requesterasking you where to put
the file. It is recommended that you put compressed files into a temporary
directory, unsqueeze them, and move the resulting files to a different directory.
Thispermitsscreeningandorganizing.
FrPtransfers
Instructionsvaryalittlefor variouscomputercenters, butthe mainideaisto invoke
the FrP system and to type in the electronic address. You move to the desired
directoryand find thefile thatyou want. The file maybe ASCIIorbinary,and you
will get gibberish if you download a binary file with your option set for ASCII.
Often the programs are compressed to save storage space. This saves time for
transmission, but you must have a program for unsqueezing them. These are
ubiquitous, and a few phone calls to your knowledgeable friends will locate
whateveryou need. Youdotheunsqueezingrightonyourpersonalcomputer.
The steps are as follows: use your personal computer, modem, and communication
software to connect to your computer center (many people are already connected
throughaterminalonthe system);entertheaccountnumberand password assigned
to you by your center; invoke the FrP program; type in the electronic address; the
distantsystemshouldrespond that you areconnected and will ask for your account
number. You seldomhavean account on aremote computer, so you type in either
upper or lower case ANONYMOUS as your account and your e-mail address (or
GUEST) as your password. The system should respond that you are admitted but
that some restrictions apply. You must then move to the directory or subdirectory
that has the programs. Commands that you need over and over are cd (change
directory) and Is(listthe files). Ifadisk full ofprograms has beendeposited in the
xii Preface
collection. you may have to download them as one large file. Usually this is
possible. buttherearealso the individualfiles. Thedownloading maybevery fast
forasingle file and abouttenseconds (onagoodday withadirect link) for the file
representing an entire disk. The names are case-specific; you must type caps or
lowercase namesexactlyas shown. Youcandownload to yourpersonal computer
or to your account at your computer center. It is faster to save to your account
because the long-distance transmission through a modem can require many
retransmissions when a noisy phone line corrupts some sections of the transfer.
Each segmentis checked and sentagain iferrors are found. Local phone lines are
less likely to be noisy when you transfer from your account to your personal
computer. Beware of space requirements. Your account may not have room for
programsequivalenttoanentirefloppydisk. and youmustrequestadditionalspace.
Downloading from your computer center to your personal computer through the
phone lines is relatively slow. When it finally is on your computer. you usually
havetounsqueezethedownloadedmaterial.
All of our programs are free for downloading from the RPI computer center.
Downloadingwhilebrowsingthewebiseasiest,butFTPmaybemoreconvenientif
you do not know how to get images. The address for the old BASIC programs is
FfP.RPI.EDU,and thedirectoryisPUB/faculty/bungay. The webaddressescanbe
seen on the screen of your browser. Most files are in ASCII format and are not
compressed. Programs change from time to time to fix bugs and to improve them.
Browsingthe webisthebestupdatingserviceforourprograms. Forcustomerswho
don't wantto workwith modemsand withprograms for using them, you can send
aformatted disk withreturnpostage to the authorevery yearor so for free updates.
This free service is available to persons who have purchased the book; others are
expectedto includean additional $5 overthe costofpostage. Besure to label your
disk with your name and the Macintosh or PC-compatible format desired (several
files that work with commercial programs for Windows have no Macintosh
equivalent).