Subject: Re: Good Technical Books?
From: ch1grh@sunc.sheffield.ac.uk (G Harris)
Date: 17 Dec 1996 09:56:37 GMT
Chris Hecker (checker@netcom.com) wrote:
: blosskf@apci.com (Karl F. Bloss) writes:
: >* Numerical Recipes in C/FORTRAN
: Anyone thinking of using the algorithms NR should look at this page:
: http://math.jpl.nasa.gov/nr/
: The page starts with, "We have found Numerical Recipes to be generally
: unreliable," and then goes on to show why.
For the other side of the story, it is probably worthwhile
to look at a rebuttal from Numerical Receipes:
http://nr.harvard.edu/nr/bug-rebutt.html
and to visit their homepage:
http://cfata2.harvard.edu/nr/
In a nutshell, they say that many of the supposed bugs are
misunderstandings, and that in the case of genuine bugs,
these have pretty much been fixed by the second edition.
I am neutral in this debate. Anyone who accepts an algorithm
or piece of code without testing it or checking out alternatives
shouldn't be programming. My own experience with NR has been fine
(eg Runge-Kutta, root-finding etc), but I've found one generally
has to do a "driver routine" oneself, (but then the authors
recommend doing just that).
-------------------------------------------
Glen Harris, Chemistry, Sheffield Univ, GB.
tel.: 44-114-2824518, fax: 44-114-2738673
email: g.r.harris@sheffield.ac.uk
www: http://www.shef.ac.uk/~ch1grh/
-------------------------------------------
Subject: Re: iRMX OS - Where to buy?
From: "Jean-Christophe Monfret"
Date: 17 Dec 1996 10:17:25 GMT
You can find iRMX at :
http://www.radisys.com/irmx.html
And contact at :
http://www.radisys.com/contacts.html
J-C.
--
__________________________________________________________________
| | |
| Jean-Christophe Monfret | Tel: 32 2 523 24 62 |
| RTUSI | Tel: 32 2 520 83 09 |
| 23, Rue de la Justice | |
| 1070 BRUSSELS | mailto:jcmon@rtusi.com |
| BELGIUM | URL: http://www.rtusi.com |
|__________________________|______________________________________|
The First online Real-Time Encyclopaedia:
http://www.realtime-info.be
RTUSI is member of http://www.GRoupIPC.com
Ray Minich <73444.1755@CompuServe.COM> wrote in article
<594f99$7ti$1@mhafc.production.compuserve.com>...
> My interest in the iRMX kernel has been piqued by the recent
> press. Where can I buy a copy of the system, how does one get
> technical specs and info on the system? Does it work under/with
> MSDOS-6.22?, Win 3.1, 3.11, 95?
>
> Any and all advice on this software would be greatly appreciated.
>
> Thanks and regards,
>
> Ray Minich
>
> --
> If it don't fit, force it... If it still don't fit, get a bigger
> hammer.
>
Subject: FS Chiller Analysis Manual
From: heatscan@kalama.com (Gerhard N. Thoen)
Date: 16 Dec 96 16:06:00 GMT
Our new manual shows how to set up an analysis program using vibration,
infrared thermography and ultrasonic analysis as well as spectrographic
oil analysis on Chillers and Heat Pumps while they are operating. Several
actual examples are presented with accompaning data/reports. This is a
real "How to" book written in standard, simple terms and should be a must
for those operating or maintanining Chillers and Heat Pumps.
^^^^
How to Analyze Chillers/Heat Pumps Manual
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Table of Contents-
NEED FOR ANALYSIS
Equipment -Types/Systems
Service
Cost of outages/collateral damages
Cost of replacement
NON DESTRUCTIVE TESTING(NDT)
Vibration
Axes of measurements
Ultrasonics
Leaks-air/refrigerant
Infrared Thermography
Heat losses
Electrical systems
COMPUTER ANALYSIS
Mass/Energy Balance/Performance
Spread Sheets
Data Collection/entry
MAINTENENACE SCHEDULES/COSTS
TROUBLESHOOTING SYSTEMS
APPENDIX-Actual cases/results
REFERENCES
Comes in a 3 ring notebook,61 pages-Drawings, Photographs, Charts, Tables
Cost is $65 + $3.80 S/H USA
Information at E mail: heatscan@kalama.com
Tele: 360 423-7167
Subject: Contact problem with ANSYS
From: kassim@me.queensu.ca (Kassim Abdullah)
Date: 17 Dec 1996 17:47:10 GMT
Hello every body,
I am doing a 3-d finite element analysis of a component which has Morse taper
connection. My model has worked well with CONTAC52 node to node contact
elements in a case where I had perfect match between two contact surfaces
(i.e no angular mismatch) and very small interfacial motion. Now, I want to
include the effect of angular mismatch between male and female tapers, in
which case, I may have bigger relative motion at the interface. To begin
with, I thought it would be easier to model my contact with CONTAC49, node to
surface contact elements. But, on running the model, I found out that life
was to smooth as I expected. Firstly, I had a huge number of warning messages
which reads like : "Contact node #### is in contact with more than one
target. Check your results carefully" ["####" represent the node number].
Secondly, my results were far away from the established theoretical
expectation.
The way I created elements at the interface is that, I had same line-element
division (lesize) of the curved lines of both male and female parts.
I am doing static analysis using substructuring.
Is there any body out there who have experience with similar use of CONTAC49
who I can contact for more sepecific questions I have?
Thanking you in adavance.
Sincerely,
Kassim.
--
=========================================================================
| Kassim A. Abdullah : Tel: (613) 549 7596 (Home) |
| Dept. of Mech. Eng., Queen's Univ. : (613) 545 6730 (Work) |
| Kingston, ON., K7L 3N6. CANADA. : Fax: (613) 545 6489 (Work) |
| e-mail: , |
| WWW Home Page |
*************************************************************************
Subject: Re: What's in a Job Title ?
From: dave lawson <71202.1577@compuserve.com>
Date: Tue, 17 Dec 1996 15:11:10 -0800
Rob Russell wrote:
>
> Glenn Thomson bashed its head on a keyboard, resulting in:
> : I'd like to know what locomotive engineers and stationary engineers call
> : themselves in your part of Ontario, then.
>
> As in the rest of Canada, "locomotive engineers" call themselves
> "hoggers." As a P.Eng with the railway, my father always went out of his
> way to correct people that called them engineers by telling them it was
> pronounced differently (ingin-eers or something) but they call themselves
> hoggers.
>
> Whether it is common practice or not, still doesn't make it right. The
> PEO (and other organizations) should make more of an effort to dissuade
> the improper use of the term "engineer."
>
> -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
> Robert Russell \ / Rob_Russell@Ottawa.Com
> Carleton University x--o8o--x 2nd Year, Mech & Aero Eng.
> http://wabakimi.carleton.ca/~rrussell
> Director of Publications, Carleton Student Engineering Society
> -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
> "No harm was done to my mental well-being." -- erdem@engsoc
It sounds like hoggers is a pretty good term for engineers.
Dave
Subject: Re: Pipe thread standards?
From: Ben Tansley
Date: Tue, 17 Dec 1996 21:57:23 +0000
In article <59438k$nr5@netnews.upenn.edu>, George Jefferson
writes
>Is there such a thing as a metric tapered thread pipe fitting?
>What do they use in europe for basic houshold piping?
>
>As an aside, unless its quite a rough vacuum I would suspect its
>not a thread seal fitting at all. Possably some sort of flare or
>specialty vacuum fitting(?).
>
>
In Europe we have a series of metric screw threads such as M6x1 (6mm outside
diameter, 1mm pitch), or M6 if you assume the medium pitch for the size.
For gas threads and pipe ends we use the old BSP (British Standard Pipe) system.
In the UK you used to see threads called such things as 1/4"BSPT M (T/P =
Taper/Parallel, M/F = Male/Female). Now we call them such things as R1/4
(=1/4"BSPTM) and G1/4 (=1/4"BSPPM), with female threads taking subscripts such
as Rc.
But you're right - this may be irrelevant. I'm betting it's an SAE thread.
--
Ben Tansley.
Subject: Re: Pipe thread standards?
From: actech@southwind.net (Dennis)
Date: Wed, 18 Dec 1996 00:07:59 GMT
tphares@uclink.berkeley.edu (Theodore Henry Phares) wrote:
>Hi,
>I have a vacuum cup with a 1/8" dia. nipple coming out of it.
>Unfortunately, the nipple is not threaded NPT, and I can't figure out what
>it is. It's close to 1/8" NPT, but not quite. Could it be NPS? Or is
>there another pipe thread standard w/o a taper? Is NPS usually used on
>pneumatic/vacuum stuff like this? To confuse the situation, I have some
>coiled air line that has NPT fittings.
How about you drill it out and tap it to 1/4" npt so you can use what
you have on hand?
-Dennis-
--
Peace cannot be kept by force. It can only be achieved by understanding.
ALBERT EINSTEIN (1879–1955)
Subject: Re: PVC pipe structural properties
From: Fred Tully <#fredtull@compusmart.ab.ca>
Date: Tue, 17 Dec 1996 17:15:00 -0700
William Melrose wrote:
>
> steven bomba wrote:
> >
> > I am trying to design a few simple PVC pipe structures for hobby use.
> >
> > Does anyone know of a source of structural properties that I can use as
> > a guide for roughing out the design?
> >
> > thanx.
> >
> > steven.
Connections are difficult. It tiers easly. The modulus is low so it
deflects alot. 1/2 bolt through 2 inches from the end 1.5 in black pvc
we get here will tare out at about 400 lbs. Tension of the pipe is a
lot more. Compression, buckling at 24 Inches long is more than 1/2 inch
bolt. Longer buckles very easy. Screws into a wood plug worked well for
connections to wood.
Best used as pipe to drain water.
--
Fred Tully
Canadian Virtual, Leduc, Alberta, Canada
email address ------fredtull@compusmart.ab.ca,
site at http://www.compusmart.ab.ca/fredtull
(403) 986 9896 fax (403) 986 9442
Civil - Structural Engineer, turned part time computer tutor in Win95,
Word 7.0, PowerPoint 7.0, Excel 7.0, Simply Accounting 4.0, Internet,
HTML, NetScape and general computer Consultant
Net site Development and Net Site Development training.
Virtual Classroom CD-ROMS, Win95, PowerPoint 7.0
Subject: Re: What's in a Job Title ?
From: Norman Kwok
Date: 18 Dec 1996 03:54:12 GMT
glenn.thomson@comdev.ca (Glenn Thomson) wrote:
>
>I'd like to know what locomotive engineers and stationary engineers call
>themselves in your part of Ontario, then.
>
>Cheers,
>
>Glenn Thomson, P. Eng.
>
You've raised an interesting point but tell me this, when was
the last time you received a business card from a locomotive or
stationary engineer?
In Canada,stationary engineering is a licensed trade. Stationary
engineers have to pass an interprovincial exam to qualify.
Professional engineering statutes in Canada often include an
exemption for stationary engineers.
Cheers,
T.Kwok
Subject: How about an .Ansys newsgroup?
From: enrique.juaristi@crpht.lu (Enrique Juaristi)
Date: Wed, 18 Dec 1996 11:30:49 +0100
I am a regular Ansys user, and I have posted a few mails asking precise
questions about some aspects of the package. Other people have done the
same, and I have noticed an increase of these messages lately. I think
it's very useful to be able to ask for advice about very specific aspects
of the software, such as nonlinear analyses and convergence,"exotic"
elements, and others.
Since the Newsgroups are practically the only way we can get free hints
and info on this software, why not create a forum to make this exchange
easier?
Assuming, of course, that there are not only questions and some people can
actually give answers to requests, of which I am convinced.
If you agree with this, please reply to this message on the newsgroups. I
am not familiar with the workings of the Newsgroups, but if we are enough
interested people we might create something worth the while!
--
Enrique Juaristi, mechanical engineer
Subject: Re: What's in a Job Title ?
From: glenn.thomson@comdev.ca (Glenn Thomson)
Date: 18 Dec 1996 13:53:24 GMT
In article <32B7288E.63CA@compuserve.com>,
dave lawson <71202.1577@compuserve.com> wrote:
>Rob Russell wrote:
>>
>> Glenn Thomson bashed its head on a keyboard, resulting in:
>> : I'd like to know what locomotive engineers and stationary engineers call
>> : themselves in your part of Ontario, then.
>>
>> As in the rest of Canada, "locomotive engineers" call themselves
>> "hoggers." As a P.Eng with the railway, my father always went out of his
>> way to correct people that called them engineers by telling them it was
>> pronounced differently (ingin-eers or something) but they call themselves
>> hoggers.
>>
>> Whether it is common practice or not, still doesn't make it right. The
>> PEO (and other organizations) should make more of an effort to dissuade
>> the improper use of the term "engineer."
>>
>> -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
>> Robert Russell \ / Rob_Russell@Ottawa.Com
>> Carleton University x--o8o--x 2nd Year, Mech & Aero Eng.
>> http://wabakimi.carleton.ca/~rrussell
>> Director of Publications, Carleton Student Engineering Society
>> -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
>> "No harm was done to my mental well-being." -- erdem@engsoc
>
>
>
>It sounds like hoggers is a pretty good term for engineers.
>
>
>Dave
Rob, old boy:
1) I didn't bash my head on the keyboard. Grow up.
2) A former landlord of mine always referred to himself as a locomotive
engineer. Anecdotes can prove anything.
3) Stationary engineers?
To the best of my knowledge, the PEO only gets its knickers in a twist if the
phrase "professional engineer" is used. Either word by itself seems to be
acceptable to the governing body. I've seen ads for 'professional balloon
decorating'! I'd like the PEO to tighten up on the use of engineer as well,
especially when employers are looking for sales/repair types.
Sorry to piggyback on your posting, Dave.
Cheers,
Glenn
Subject: Re: How about an .Ansys newsgroup?
From: rongraham1@aol.com
Date: 18 Dec 1996 14:25:11 GMT
In article ,
enrique.juaristi@crpht.lu (Enrique Juaristi) writes:
>I am a regular Ansys user, and I have posted a few mails asking precise
>questions about some aspects of the package. Other people have done the
>same, and I have noticed an increase of these messages lately. I think
>it's very useful to be able to ask for advice about very specific aspects
>of the software, such as nonlinear analyses and convergence,"exotic"
>elements, and others. [...]
>Since the Newsgroups are practically the only way we can get free hints
>and info on this software, why not create a forum to make this exchange
>easier? [...]
About the only thing I can say about this suggestion is that the way
Usenet is currently set up, software tools that engineers use have
their newsgroups in the comp.* hierarchy. That's probably where they
"belong," though such placement clearly makes them difficult for
engineers to find, since they always come to the sci.engr.* groups
looking for them first. We see an inquiry about Matlab, for instance,
about once a month. To me that's not excessive, but it should be
noted if you're looking to start an Ansys group.
Your proposed group would either go in the comp.cad hierarchy (like
AutoCAD and I-DEAS) or comp.soft-sys (like Matlab). Interested
folks might want to check how those hierarchies are set up to see
which is the right one.
Dr. Ron Graham
Project Engineer for Robotics, GreyPilgrim LLC, Washington DC
founder of Usenet newsgroup sci.engr and keeper of its FAQs
EMMA Robotic Manipulator online -- http://www.greypilgrim.com/
Subject: Re: Qualification for P.E Exam
From: "Brian A. Rock"
Date: Wed, 18 Dec 1996 08:11:24 -0800
C P GOPALAKRISHNAN wrote:
>
> hai all:
>
> What is the qualification to take a P.E.Exam after one's EIT.?
>
> To be more specific, how many years of experience does one need? Does it
> have to be under a P.E.? Is it same in all states?
>
> Thank you for your help!
>
> gopal
Contact your state's board of technical professions. They will send you
the requirements which vary from state-to-state. Most states seem to
require four years of engineering experience. Many states give some
credit toward the experience requirement for graduate degrees in
engineering or work as a co-op.
--
-----------------------------------------------------------------------
Brian A. Rock, Ph.D., P.E. Voice: (913) 864-3434
The University of Kansas Fax: (913) 864-5099
Architectural Engineering Dept. E mailto:barock@ukans.edu
Marvin Hall Home page: http://www.arce.ukans.edu/
Lawrence, Kansas 66045-2222 Rock Chalk, Jayhawk, KU!
-----------------------------------------------------------------------
Subject: Machine Design 12/12/96 provoking editorial
From: rongraham1@aol.com
Date: 18 Dec 1996 14:25:14 GMT
I was provoked by an editorial in the 12/12 issue of Machine
Design, written by Ronald Khol. It's entitled "How people get
killed on the road," and his point is that there appears to be
almost no relationship between freeway speeding and traffic
fatalities. Whether he has a point here I cannot tell: it seems
to me the purpose of speed traps is to discourage speeding,
and so one might argue that if speed-related fatalities are down
in areas where there are speed traps, they work. :-)
But he goes on to say the following:
"The American Civil Liberties Union might be interested to know
that drivers fleeing police caused 9% of fatal crashes. To me
this shows we need prompt use of deadly force to bring such
chases to a quick conclusion."
In other words, we have to kill someone before someone gets
killed. Regardless of the reason for the flight.
Then he blamed the volume of accidents caused by teenagers
on "time on their hands." No consideration that teenagers in
accidents might actually have quite the opposite consideration:
on the way to (or from) work, practice, etc. In short, no insight
into any factor other than age.
My feeling was that this was not the kind of clear thinking I
expect from an engineer, especially one with such influence
as is found in the Editor of a major trade publication. So I
e-mailed him about it.
I don't expect you to agree with me about my feelings on the
editorial, but I encourage you to read it and draw your own
conclusions. Machine Design is at http://www.penton.com/md
-- I wonder if they publish these editorials online?
Dr. Ron Graham
Project Engineer for Robotics, GreyPilgrim LLC, Washington DC
founder of Usenet newsgroup sci.engr and keeper of its FAQs
EMMA Robotic Manipulator online -- http://www.greypilgrim.com/
Subject: Hardnose checkers (was something else)
From: klingener@aol.com
Date: 18 Dec 1996 15:46:43 GMT
In article <32B5AA85.4E41@den.mmc.com>, "David E. Pearce Jr."
writes about an integrated design package:
> The drafting package could also be better, but it is
> adequate, especially if you don't have a hardnose checking staff.
There is no substitute for a hardnose checking staff. The best ones will
provide the moral leadership for the whole design organization. They
should be feared by drafters and engineers alike. If you don't have one,
get one. If a particular design package causes you to retrain or
deengineer the one you have, then it's wrong.
There are many attributes that go into making a good checker. They
include: nasty and suspicious underlying disposition, attention to
detail, loyalty to the organization, sense of pride in the work. When
these can be captured in software (course the nasty disposition is already
built into Windows95), then you'll have a decent design package.
Cheers,
Fred Klingener
---------------------------------------------
Fred Klingener
Brock Engineering PC, Roxbury CT
klingener@aol.com
---------------------------------------------
Subject: Re: Flow loss past coupling.
From: Bill Jaques
Date: Wed, 18 Dec 1996 06:34:33 -0400
R wrote:
>
> In article <32AC5594.2241@cfer.ualberta.ca>, Paul Skoczylas says:
> >
> >A rod is run through a length of vertical pipe. The rod is not
> >continuous, but is in discrete sections which are attached together with
> >couplings which have a larger outside diameter than the rod itself. The
> >difference in the diameters of the rod and coupling are significant
> >relative to the pipe's internal diameter.
> >
> >| | | |
> >| | | |
> >| | | |
> >| | | |
> >| - - |
> >| | | |
> >| | | |
> >| | | |
> >| - - |
> >| | | |
> >| | | |
> >| | | |
> >| | | |
> >
> >Fluid flows vertically upward in the annular space between the pipe wall
> >and the rod/coupling. The fluid can range from water (1 cp) to very
> >viscous fluids (>8000 cp, possibly up to 100,000 cp). What we need to
> >calculate is:
> >
> >1. The flow loss (pressure loss) past the coupling. Flow rates are
> >such that the flow will always be laminar (esp. with viscous fluids).
> >Right now we are not considering the effects of the change in diameters,
> >but rather are considering the loss in an annulus of the length of the
> >coupling. This may or may not be a good approximation. Any
> >suggestions?
> >
> >2. The axial force on the rod caused by fluid flowing past the
> >coupling. Right now we are only using the estimated differential
> >pressure across the coupling multiplied by the difference in
> >cross-sectional areas of the rod and coupling. There is presumably some
> >drag effects, by the flow along the surface of the coupling, plus some
> >effects caused by the change in direction of the fluid to get around the
> >coupling, plus the fact there is probably a low pressure wake behind the
> >coupling. Does anyone have some suggestions for calculating these
> >effects?
> >Thanks!
> >-Paul
>
> As the fluid flows past the coupling it will experience a sudden contraction
> and then a sudden enlargement of the flow area. There are many sources of
> data related to such changes of area and thus of velocity and momentum. The
> easiest to find and use is probably Crane Technical Paper 410, which the
> Crane Company often give away but is about $10 if you have to buy it. Many
> tech libraries carry it.
>
> In addition to the losses due to sudden area change, there will be the
> normal friction loss of the higher velocity flow through the annulus at
> the coupling, but this will be very small compared with the entrance and
> exit losses. One problem is estimating the effective length of each
> coupling, but using the actual length will be close enough.
>
> If the couplings are rounded at each end, as they would normally be, the
> entrance and exit effects will be modified by a factor which, again, may
> be estimated from Crane Tech Paper 410.
>
> The upthrust on the rod will be close to the total of the losses due to
> entrance, friction and exit effects, over and above the friction on the
> remainder of the rod, all related to the diameter of the rod or fitting
> where they occur.
In addition to the above I would expect the friction losses along the
lengths of the couplings and rod to be double that which would be
encountered at the same velocities in pipe without the rods/couplings in
them; in the former the fluid friction is against the pipe surface and
the coupling/rod surface while in the latter the fluid friction is
against only the pipe wall.
Subject: Re: What's in a Job Title ?
From: glenn.thomson@comdev.ca (Glenn Thomson)
Date: 18 Dec 1996 17:08:06 GMT
In article <597pt4$7os@carrera.intergate.bc.ca>,
Norman Kwok wrote:
>glenn.thomson@comdev.ca (Glenn Thomson) wrote:
>
>>
>>I'd like to know what locomotive engineers and stationary engineers call
>>themselves in your part of Ontario, then.
>>
>>Cheers,
>>
>>Glenn Thomson, P. Eng.
>>
>
>You've raised an interesting point but tell me this, when was
>the last time you received a business card from a locomotive or
>stationary engineer?
Never, but why does this matter? If I lose my job and don't have any business
cards, do I lose my professional standing as well?
>In Canada,stationary engineering is a licensed trade. Stationary
>engineers have to pass an interprovincial exam to qualify.
Exactly my point. I doubt they are going to give up the title because
P.Eng.'s don't like it.
>Professional engineering statutes in Canada often include an
>exemption for stationary engineers.
What about all the other 'engineer' titles?
>Cheers,
>
>T.Kwok
>
Glenn
Subject: Re: Machine Design 12/12/96 provoking editorial
From: hobdbcgv@aol.com (Hobdbcgv)
Date: 18 Dec 1996 16:40:02 GMT
If you are accurately quoting the editorial---
The editor is out to lunch or it is the April Fool's day issue. The
magazine obviously has been taken over by right-wing pseudo-liberal
NewYork-leftist- leaning-moved-to-Atlanta wimp insensitive non-engineers.
That editor is clearly a liberal arts major who has found thought but
dislikes using facts which disagree with their true view of the world.
They probably also dislike the arrogance of contributing engineers who
submit articles based on carefully prepared studies rather than on etheral
thought, which all persons who avoid hard work, such as doing studies that
may prove themselves wrong, know is sooo hard to think about it makes your
head hurt and is so neat it mustn't be challenged by something as earthly
as hard evidence.
9%, eh? 3500 deaths from high speed chases? 70 per state? Lordy, if
they're right, then we better mount twin fifties on every police car to
cut down that violator before he gets up to speed. That'll take care of
that "high speed" statistic right quick.
Teenagers with time on their hands, ay? Let's cut those hands right off,
and that'll fix that one. Jees, I love the Limbaugh approach to problems.
It's so..so..clean.
On a serious note... I noticed you did not say "thought" provoking
article. Were you possibly implying the editorial writer had taken one too
many hallucogenic lunches? (Why is that word so hard to spel?)
Take care- and don't downer those heavy thoughts with facts, man......
Subject: Re: What's in a Job Title ?
From: Kevin Jones
Date: Wed, 18 Dec 1996 13:11:46 -0800
Norman Kwok wrote:
>
> glenn.thomson@comdev.ca (Glenn Thomson) wrote:
>
> >
> >I'd like to know what locomotive engineers and stationary engineers call
> >themselves in your part of Ontario, then.
> >
> >Cheers,
> >
> >Glenn Thomson, P. Eng.
> >
>
> You've raised an interesting point but tell me this, when was
> the last time you received a business card from a locomotive or
> stationary engineer?
>
> In Canada,stationary engineering is a licensed trade. Stationary
> engineers have to pass an interprovincial exam to qualify.
>
> Professional engineering statutes in Canada often include an
> exemption for stationary engineers.
>
> Cheers,
>
> T.Kwok
It's a little more than writing an "interprovencial exam" to qualify.
I am a Stationary Engineer, have business cards, and have never
written an interprovencial exam.
Tx,
K. Jones
Subject: indycar parameters
From: "B.J. Jasinski"
Date: Wed, 18 Dec 1996 14:19:49 -0600
hi all,
i'm doing a project for a class which involves a lap-time simulation of
an indycar. i have been researching the parameters (i.e. geometry,
mass, moment of inertia) of the whole car and various parts of the car
that i need, and i would like to get some verification if anyone knows
more than i do.
here's the parameters i am having trouble determining:
Chassis:
--------
mass=715kg (i have also found other values up to 905 kg, i'll
probably use an average of the 2)
Izz=1525 kgm^2 (by approximating the chassis as a rod, and
wheels as point masses, i calculated 775 kgm^2.
which is closer? i got the 1525 kgm^2 from SAE
paper 910012, but i'm not sure i believe it)
Af=1.0 m^2 (frontal area - i estimated this from car
drag mesasurements)
Engine:
-------
Power=850hp (634kW)
Max RPM = 13800 (1445 rad/sec)
These values give an engine torque at max rpm of 438Nm, is this
realistic?
Final Drive Ratio= 4.09 (got this from SAE paper 910011 for a 5th gear,
is this also realistic?? estimating some
values i calculated 3.25)
Wheels:
-------
radius = 0.33m
Iyy = 0.89kgm^2 to 1.29kgm^2 (i will most likely average these values
for the final simulation.)
just in case it matters, the project is due on friday, and i would
appreciate a quick response.
thanks in advance,
b.j.
--
B.J. Jasinski
Graduate Research Assistant
Department of Aeronautical & Astronautical Engineering
University of Illinois at Urbana Champaign
(217) 244-0492 fax: (217) 244-0720
e-mail: wjasinsk@uiuc.edu
http://www.students.uiuc.edu/~wjasinsk/
"Without love in a dream, it will never come true..."
Subject: Re: What's in a Job Title ?
From: colonel@engsoc.carleton.ca (Rob Russell)
Date: 18 Dec 1996 20:15:00 GMT
Glenn Thomson bashed its head on a keyboard, resulting in:
: Rob, old boy:
: 1) I didn't bash my head on the keyboard. Grow up.
I know you didn't and your condescending tone is patronizing. If I wanted
a flame war I wouldn't be in a professional newsgroup. Let's stay on
topic.
: 2) A former landlord of mine always referred to himself as a locomotive
: engineer. Anecdotes can prove anything.
Okay. Point taken. I don't know what term their union uses, but I'll
look it up.
: 3) Stationary engineers?
I left it out because I had nothing to contribute to that side of the
conversation. Someone else answered that question without mentionning
locomotive engineers - go pick on him too.
Ciao -
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Robert Russell \ / Rob_Russell@Ottawa.Com
Carleton University x--o8o--x 2nd Year, Mech & Aero Eng.
http://wabakimi.carleton.ca/~rrussell
Director of Publications, Carleton Student Engineering Society
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
"No harm was done to my mental well-being." -- erdem@engsoc
Subject: Re: Thermal Conductivity SW
From: ddcrouch@ccgate.hac.com (Dave Crouch)
Date: Wed, 18 Dec 1996 21:36:27 GMT
Jon wrote:
>Does anyone know of any software packages for Thermal Conductivity
>through solids in 3D? I have been this asked by our Engineering Dept.
>and haven't a clue of where to turn. I appreciate any help you could
>give me.
>Thanks,
>Jon A. Brown
>Osram Sylvania Glass Technologies
>Exeter, NH
>brownj@osi.sylvania.com
>brownjon@ix.netcom.com
Jon,
I've been using finite-difference packages SINDA/G and SINDA3D.
SINDA3D is a DOS-based GUI for SINDA/G. SINDA/G is quite versatile;
it can handle transient as well as steady-state heat conduction
problems in one, two, or three dimensions. The software is marketed
by Network Analysis, Inc. I think you can download a demo version at
their web site, www.sinda.com. Hope this helps.
Dave Crouch
Hughes Aircraft Company
ddcrouch@ccgate.hac.com
Subject: Re: Hardnose checkers (was something else)
From: Pat March
Date: Wed, 18 Dec 1996 04:44:00 -0800
klingener@aol.com wrote:
>
> In article <32B5AA85.4E41@den.mmc.com>, "David E. Pearce Jr."
> writes about an integrated design package:
>
> > The drafting package could also be better, but it is
> > adequate, especially if you don't have a hardnose checking staff.
>
> There is no substitute for a hardnose checking staff. The best ones will
> provide the moral leadership for the whole design organization. They
> should be feared by drafters and engineers alike. If you don't have one,
> get one. If a particular design package causes you to retrain or
> deengineer the one you have, then it's wrong.
>
> There are many attributes that go into making a good checker. They
> include: nasty and suspicious underlying disposition, attention to
> detail, loyalty to the organization, sense of pride in the work. When
> these can be captured in software (course the nasty disposition is already
> built into Windows95), then you'll have a decent design package.
>
> Cheers,
>
> Fred Klingener
Howdy, Fred
You are exactly right! Since I "retired" I find that my most egregiuos lack is
a CHECKER. With guts. With an ulcer. With enough knowledge to tell me I am wrong.
He may not be right in telling me I am wrong. But at least somebody is there to call
my design details into question.
How I miss the CHECKER!!
Pat - Old Engineer Guru at SKONK WORKS
Subject: Re: Contact problem with ANSYS
From: fog86@aol.com (Fog86)
Date: 18 Dec 1996 22:26:33 GMT
Kassim,
Regarding your post to sci.engr.mech about contact problems with ANSYS:
My first suggestion would to be start out with a 2D analysis. If its a
morse taper you're analyzing try using axisymmetric plane42's with
contac48's (if at all possible), then upgrade to 3D. Be careful with
creating general contact elements using lines. I prefer to generate them
on some dummy solid elements so that I guarantee that the normals are
right (if they're wrong then the elements act something like velcro!) See
the element descriptions for 48 and 49.
Other thoughts/suggestions:
Often with contact, I have found that I need to use much more contact
elements than you might think, especially with sliding contact. It's the
contact nodes leaving one target and going to another that seems to give a
lot of problems. It took me a while to get sliding contact down, but I've
had little problems since.
Although I can't recall any problems I've had with it, it is not
recommended to use elements with midside nodes on the contact surface.
If convergence is your problem, use lots and lots of substeps, and turn
the predictor off. In fact, I'd start out using neither adaptive descent
nor line search. Make your contact stiffness a small as you can stand. I
usually use symmetric contact, i.e., nodes and targets on each surface
(gcgen,target,surface gcgen,surface,target sort of stuff) with a contact
stiffness of 100 GPa for hardened steel surfaces (metalworking analyses).
When it comes to substeps, I usually let ANSYS decide. I use automatic
time stepping with a reasonable starting number that depends on how the
contact will be initiated and give a seemingly ridiculous max number, like
100000. Just keep an eye on the convergence numbers and if it's not going
anywhere then stop it and try again. You may need to adjust your
convergence tolerences (CNVTOL command), especially if you are using a
displacement loaded system. Making the convergence criteria smaller NOT
bigger is usually helpful. This keeps ANSYS closer to convergence on each
substep, therefore keeping it on track for the following substeps.
I hope I've been helpful. If you would like any more assistance, just
e-mail me.
Regards,
-Will Gardner
fog86@aol.com
Subject: Re: Ansys vs. MSC FEA Software
From: parasnis@asimov.ecn.purdue.edu (Narasinha C Parasnis)
Date: 18 Dec 1996 23:02:04 GMT
"PaulK" writes:
>In an evaluation of both packages, weaknesses and strengths can be seen
>between the two. To truly determine the capabilities of either analysis
>package one must ask a user.
>If you are are a user of either Ansys or MSC, I would greatly appreciate
>some feedback (positive or negative).
>Thank You,
>Paul
>Note: please no sales pitches, only real experiences
One thing you should look for is technical support, if you are
going to solve problems other than those in their tutorials.
I have had pretty bad experience with ANSYS. Since I am
a University student, they dont provide technical support per se
"I guess Universities dont pay them enough".
On sending email, you wont even know whether they have looked at it
. I dont know about Nastran since I havent used it.
--
Narasinha Chandrakant Parasnis
School of Mechanical Engineering (ME 58), Purdue University
West Lafayette, IN 47907-1288 Phone (317) 496-2792
Subject: Re: How about an .Ansys newsgroup?
From: parasnis@asimov.ecn.purdue.edu (Narasinha C Parasnis)
Date: 18 Dec 1996 23:04:46 GMT
enrique.juaristi@crpht.lu (Enrique Juaristi) writes:
>I am a regular Ansys user, and I have posted a few mails asking precise
>questions about some aspects of the package. Other people have done the
>same, and I have noticed an increase of these messages lately. I think
>it's very useful to be able to ask for advice about very specific aspects
>of the software, such as nonlinear analyses and convergence,"exotic"
>elements, and others.
>Since the Newsgroups are practically the only way we can get free hints
>and info on this software, why not create a forum to make this exchange
>easier?
>Assuming, of course, that there are not only questions and some people can
>actually give answers to requests, of which I am convinced.
>If you agree with this, please reply to this message on the newsgroups. I
>am not familiar with the workings of the Newsgroups, but if we are enough
>interested people we might create something worth the while!
That should be a good idea. I have used the comp.sys-soft.matlab
group often, and it has been very useful. It would be good to have
a ansys newsgoup as well
--
Narasinha Chandrakant Parasnis
School of Mechanical Engineering (ME 58), Purdue University
West Lafayette, IN 47907-1288 Phone (317) 496-2792
