Subject: request
From: M.T61612@neda.net (MOHAMMAD TAHERI)
Date: Mon, 2 Dec 1996 05:45:02 -0500
Dear Sir/Madam
My name is MOHAMMAD TAHERI , MSC student at TEHRAN TECH.UNIVERSITY.
I'm looking for MECHANICAL ENG. litratures in SOLID MECHANICS
(COMPOSITES), as fallow:
1- J.M Whitney, Elastic moduli of undirectional composites with
anisotropic filaments.
J.Compos.MAter.1,188-193(1976).
2- J.M.Bloom and D.F.Adams, Axial loading of a unidirectional
composite-anisotropic filaments.
J.Compos.Mater.3,186-188(1969).
3- M.D.Heaton , A calculation of the elastic constants of a
undirectional copmosite containing transversely isotropic fibers.
J.Phys.D 3,672-676(1970).
4- C.H.Chen and S.Cheng , Mechanical properties of anisotropic
fibef reinforced composites.
J.Appl.Mech.37,186-189(1970).
5- C.H.Chen ,Rectangular or square arrey fibrous composite with
anisotropic or isotropic filaments.
J.Appl.Mech.38,710-712(1971).
6- E.Behrens, Elastic constants of fiber-reinforced composites with
transversely isotropic constituents.
J.Appl.Mech.38,1062-1065(1971).
7- F.Ya.Bulavs, Ya.V.Auzukalns and A.M.Skudra , Deformation
characteristics of plastics reinforced with high-modulus
anisotropic fibers.
Polymer Mech.8,545-552(1972).
8- G.A.Ermakov, A.G.Fokin and T.D.Shermergor , Effective moduli of
lasticity for materials reinforced by anisotropic fibers.
Mech.Solids 9,98-104(1974).
I'll be pleased if you send me above mentioned litratures.
Tanking you in advance
M.TAHERI
Subject: Re: friction with ANSYS
From: "G.Quinlan"
Date: 2 Dec 1996 11:20:14 GMT
Scott Eddy wrote in article <329DA8D7.672D@eng.fsu.edu>...
> Anyone modelling friction with ansys? Need to analyze sliding friction
> effects and forces, any suggestions?
> --
> Scott M. Eddy
> Graduate Research Asst.
> Dept. of Civil Engineering
> Florida State University
>
In the contac48 and contac49 elements in ANSYS, you can set one of the KEYOPTS
to use elastic or rigid friction. You can then set a FACT figure in the real
constants for these elements which allows you to set the factor which relates
static to dynamic friction coefficients. If you need any more details, e-mail:
gquinlan@mail.tcd.ie.
Hope this helps,
Gavin Quinlan, Research Student, Mechanical Eng. Dept., Trinity College Dublin.
Subject: LUSAS
From: redesco@galactica.it (Cesare Carini)
Date: Mon, 02 Dec 1996 12:08:53 GMT
I'm a structural engineer and I have to decide what FEA package to get
for my company. I got through some packages (ANSYS, UAI-NASTRAN,
ADINA, LUSAS), and LUSAS seems to best suite my needs which are:
- static and dynamic nonlinear analysis for steel and concrete
structures (both geometric and material)
- bridge analysis (influence lines and surfaces)
- heat transfer analysis
- 3D geometric modeller (with loads, boundaries and material
properties directly applied to geometry)
- CAD interface
- concrete or steel frame element design according to some code (ACI,
AISC, Eurocodes, BS, etc) - NOT AVAILABLE ON LUSAS (any third party
applications that does it?)
- availability on PC
- WinNT, Win95, or DOS operating system (in order of preference)
- technical support
Before I come to the final decision, I would like to hear from some
LUSAS user about his feelings on the aforesaid matters.
Subject: Re: Help! Need Solenoid Valve for PWM
From: curt@hsonline.net (Curtis L. Fiene)
Date: Mon, 02 Dec 1996 12:13:34 GMT
aschoen@mo.net wrote:
>In <329F6F15.553@airmail.net>, Larry Hill writes:
>>Michael R. Whitchurch wrote:
>>>
>>> Hello!
>>>
>>> I am looking for a solenoid valve that can be controlled with pulse-
>>> width modulation. I think this may also be known as a proportional
>>> solenoid valve. I want to regulate the flow rate of water to a set
>>> of spray nozzles. The valve will be placed in-line between a
>>> centrifugal pump and the nozzles.
>>>
>>> My specs are:
>>> Fluid: Water
>>> Ports: 3/4" NPT
>>> Flow Rate: 0 - 5 GPM
>>> Pressure: 20 - 120 psi (inlet)
>>> Voltage: Any
>>> NO/NC: Either
>>>
>>> Thanks in advance for the help.
>>>
>>> Mike Whitchurch
>>
>>Check with Sporlan Valves, they have a solenoid valve designed specifically
>>for pulse width modulation. And it does take a special solenoid valve, if
>>you want it to last. I've used them and they work great. Generally used
>>for capacity control in low/medium temp refrigeration.
>>
>>Good Luck
>>Larry Hill
>>Lennox Industries Inc.
>Unfortunately, the rapid cycle type solenoid valves we make at Sporlan are
>spefically designed for refrigeration systems. We do provide a 3/4" NPT
>solenoid valves for water service: W19P2 (disc type) and R246P1 (diaphragm type),
>but neither are specifically designed for pulse width modulation.
>Andy Schoen
>aschoen@mo.net
Try an RC network on PWM output and use a proportional valve.
Subject: Re: friction with ANSYS
From: Eric R Miller
Date: Mon, 02 Dec 1996 09:02:14 -0800
Scott Eddy wrote:
>
> Anyone modelling friction with ansys? Need to analyze sliding friction
> effects and forces, any suggestions?
> --
> Scott M. Eddy
> Graduate Research Asst.
> Dept. of Civil Engineering
> Florida State University
Christopher Wright P.E. Replied:
>Last time I checked, ANSYS couldn't distinguish between static
>and sliding friction coefficients.
>I've also tried ANSYS with rigid body displacements
>and wasn't all that pleased. I was really pushing it pretty hard.
Mr Wright was not completely right (pun intended). ANSYS does
include a scale factor to calculate static friction coeficient from the
dynamic fircition coeficient in the geralized contact elements.
As for doing friction analysis, as with any code, convergence is
the issue! If you are modeling a problem in ANSYS that is
unstable in the real world, it will be unstable in ANSYS.
The knobs I turn to get things to work are:
- the rate in which I ramp up the loads
- The stiffness of the gap elements
- Minimize the number of gap elements/terms in gereralized gaps
- Make shure you constrain the model properly
- Substructure, substructure, substructre. Don't interate on
anything you don't have to!
Hope this helps
Eric
--
=======================================================================
-----------------------------------------------------------------------
Phoenix Analysis & Design
Technologies
Eric Miller
Director, CAD & Software Services
(602) 813-4884
padt@crl.com
http://www.crl.com/~padt
-----------------------------------------------------------------------
NOTE: I am not responsabal for speling; puntuasion nor grammer!
=======================================================================
Design * Analysis * Rapid Prototyping * Hardware/Software Sales
=======================================================================
Subject: Heat Exchangers,Pressure Vessels, & Boilers
From: hipressure@earthlink.net
Date: Mon, 02 Dec 1996 14:41:12 -0600
Hello:
If you are need of Boiler, heat exchanger or pressure vessel information
then you need to check out the new web site for Troy Boiler Works.
You can ask the on-line engineer any question regarding boilers,heat
exchangers, pressure vessel???
http://www.net-pros.com/troyboiler
thanks
Richard
-------------------==== Posted via Deja News ====-----------------------
http://www.dejanews.com/ Search, Read, Post to Usenet
Subject: Re: Solution strategies for non-linear finite-element analysis
From: mwcraig
Date: Mon, 02 Dec 1996 21:41:26 +0000
LADAK@bmeucl.medcor.mcgill.ca wrote:
>
> Hello,
>
> I am analyzing the geometrically non-linear behaviour of a thin elastic
> shell using the finite-element method. The solution procedure I am using
> involves incrementing the load in small steps, and at each step,
> performing full Newton-Raphson iterations to obtain displacements. At some
> load steps, the procedure fails to converge. (The convergence criterion I
> use requires that the ratio of the Euclidean norms of the iterative
> displacement vector and the total displacement vector is less than 0.001.)
> When the solution fails to converge, the convergence criterion oscillates
> in the range 0.047-0.049.
>
> 1) What can be the possible causes of this behaviour? (e.g., limit points,
> etc)
>
> 2) What solution strategies can I try?
>
>
You might want to try a relaxation type of analysis. You could also do an
analysis that mimics a dynamical one, and add some artificial damping to
limit the oscillations. Once you get to the equilibrium point the mass and
damping terms won't affect the solution.
Some problems which involve second order stability effects can be tricky
though, once you get around a point of near bifurcation of the load versus
deflection curve. The numerical noise due to finite-word-length effects might
cause problems. For that matter you might see if there is a way to use
double-precision word-length for your numbers.
Hope this was of some help.
-matt
Subject: New Website for FE-Sizer Flowmeter Sizing Software
From: CntrlSoft@flash.net
Date: Mon, 02 Dec 1996 10:08:06
*/*/*/*/*/*/*/*/*/*/*/*/*/*/-----------\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*
The website for the FE-Sizer Flow Meter Sizing software has changed!
The new website is now:
http://www.flash.net/~csoft
All FE-Size users should bookmark this new site in their browser.
Available from the new website is the updated FE-Sizer Shareware
Version 1.15 Flow Meter Sizing software. Load up the latest version
of flow meter sizing software which includes a fully functional fluid
properties database which includes a properties database of
approximately 115 fluids including ASME steam and water. For a free
"unlimited use" demonstration copy of the Shareware Version 1.15
software, visit the website at:
http://www.flash.net/~csoft
For more information, e-mail Control-Soft at:
CntrlSoft@flash.net
Incorporated flow meter standards in the sizing package are:
* ASME MFC-3M (1989) - Measurement of Fluid Flow in Pipe Using
Orifice, Nozzle and Venturi.
* ISO-5167 (1991) - Measurement of Fluid Flow by Means of Orifice
Plates, Nozzles and Venturi Tubes Inserted in Circular Cross-section
Conduits Running Full.
* ANSI/API 2530-AGA Report No. 3 (both 1985 and 1992 Versions) -
Orifice Metering of Natural Gas and Other Related Hydrocarbons - Part
3 Natural Gas Applications.
----------
Also available from the website is an ASME Steam and Water Properties
DOS utility using the 1967 IFC Correlations. It was created to
demonstrate Control-Soft's Steam Properties Class object module for
utilization in your C++ applications.
----------
Additionally, be sure to download the fully functional Cv-Sizer
control valve sizing shareware software using ISA S75.01 equations.
\\\//////
_/ _ _ \_
(o| O + |o)
+-------oOOo-+--(_)--+-oOOo--------+
| James W. Milling |
| Control-Soft Enterprises |
| e-mail: csoft@flash.net |
+----------------------------------+
| Visit the Control-Soft Website! |
| @ |
| http://www.flash.net/~csoft |
+----------------------------------+
Subject: Readers Digest LookSmart Looks Provincial
From: coolabah@coolabah.com (Coolabah Systems)
Date: Tue, 03 Dec 1996 02:15:15 GMT
Censorship through neglect? Of the nearly 20,000 USENET groups, why
has Readers Digest LookSmart targeted only 180 or so to 'review'? It
does appear in line with their apparent policy of only serving the
American community as an advertising resource. Pity the users who
believe that Readers Digest LookSmart is, a WWW search engine. A
perceptive visitor may wonder why, for example, of approximately
700,000 Australian Web pages available, Readers Digest LookSmart,
only has 30 (The Melbourne Age 26 Nov 96) .
If Readers Digest LookSmart wants to be an advertising tool, that is
clearly within their right. However, shouldn't they TELL their users
that only (or primarily) American companies are posted on their sites.
Shouldn't they SAY that they only review 180 out of 20,000 newsgroups?
To find more and to see the USENET groups Readers Digest LookSmart
selected, visit
http://www.coolabah.com/oz/controversy.html
And what is more, only 40% of the postings are clearly from Readers
Digest LookSmart personnel, whose USENET profiles are outlined below.
We encourage you to let Readers Digest LookSmart advertisers know that
the web is the WORLD Wide Web and that unstated restrictive policies
that may mislead new and uninformed users are not acceptable to the
international web community.
The following is public information available through DejaNews:
AUTHOR PROFILE: Fleur Toone fleur@homebase.com.au
47 articles posted between 1996/11/12 and 1996/11/14.
0 % of these articles were followups.
AUTHOR PROFILE: John Cussen john@homebase.com.au
27 articles posted between 1996/06/20 and 1996/11/15.
7 % of these articles were followups.
AUTHOR PROFILE: "S Banes - looksmart Intl." sbanes@looksmart.com
AUTHOR PROFILE: Sali sbanes@looksmart.com
36 articles posted between 1996/11/12 and 1996/11/29.
27 % of these articles were followups. by cross-postings):
AUTHOR PROFILE: fmaguire@looksmart.com
AUTHOR PROFILE: Fergus fmaguire@looksmart.com
7 articles posted between 1996/11/12 and 1996/11/13.
0 % of these articles were followups.
AUTHOR PROFILE: Matthew Travers mtravers@looksmart.com
38 articles posted between 1996/11/12 and 1996/11/14.
0 % of these articles were followups.
AUTHOR PROFILE: mback@looksmart.com (Meg)
3 articles posted between 1996/11/15 and 1996/11/15.
0 % of these articles were followups.
AUTHOR PROFILE: cfogarty@looksmart.com (C Fogarty)
AUTHOR PROFILE: cfogarty@looksmart.com (Conor Fogarty)
9 articles posted between 1996/11/12 and 1996/11/14.
0 % of these articles were followups.
AUTHOR PROFILE: Pete Crawford pcrawford@looksmart.com
AUTHOR PROFILE: pete
9 articles posted between 1996/11/13 and 1996/11/14.
0 % of these articles were followups.
AUTHOR PROFILE: Noel Bailey nbailey@looksmart.com
5 articles posted between 1996/11/12 and 1996/11/14.
20 % of these articles were followups.
--Coolabah systems
coolabah@coolabah.com
Subject: Re: Impact of FEA on design cycle time
From: chrisw@skypoint.com (Christopher Wright)
Date: Mon, 02 Dec 1996 20:26:52 -0600
In article <57v7k3$rj1@kocrsv08.delcoelect.com>, Rhod Fitzpatrick
wrote:
>I would be interested in any specifics regarding time and/or
>money saved by the use of engineering analysis.
I think I'd research the impact of something else. I doubt if anyone
really knows. My own opinion after some time in the biz is that it doesn't
save money or time at all. It does allow people to study physical behavior
more effectively--sometimes that's useful or even indispensable, but at
best it gives you a shot at something you might not have tried otherwise
and at worst it allows the uninformed either to study a problem to the
point of paralysis or make decisions on the basis of imagined physics.
That may sound cynical--I really do believe in the technology, but my
guess is that people whose chief concern is saving time and or money
generally don't know enough about fea to make productive decisions in
using it.
Maybe you ought to field this one, Tony. ;->
Christopher Wright P.E. |"They couldn't hit an elephant from
chrisw@skypoint.com | this distance" (last words of Gen.
___________________________| John Sedgwick, Spotsylvania 1864)
http://www.skypoint.com/subscribers/chrisw
Subject: Re: What's in a Job Title ?
From: Curtis V Palmer
Date: Tue, 03 Dec 1996 01:13:22 -0500
Nägel wrote:
>
> John H. wrote:
>
> > One who does Drafting via CAD is a CAD Technician. A person on a
> > Survey Crew is a Survey Crewman (composed of an Instrument man, a
> > Rodman and sometimes a Chainman - NOTE: replace person in place of
> > MAN to be politically correct!)
>
> I don't like the sound of technician, it makes me feel like I have a
> headset on and saying "can I take your order, and would you like me to
> include our free catalog" I've also heard the term CAD Operator but
> that's even worse.
>
> Looking at my collage diploma (which was only a 2 year course) it
> clearnly states "Commercial Engineer". I've been calling myself that
> for years and nobody has gave me a hard time about it,...... yet....
Nägel is on to the right thing here... if you call yourself a CAD
Technician (or operator or anything else) then you are tying your future
to the "tool"! Nägel's use of "Commerical Engineer" who happens to use
CAD (and probably other graphics tools, too) is more appropriate.
Never ever call yourself a "CAD " since it implies
that CAD is what you do... when instead I'll bet you design, draft,
engineer, and/or manage *WITH* CAD.
Curtis V Palmer
formerly Manager, CAD Systems, Atlanta Committee for the Olympic Games
Atlanta, GA USA
