Newsgroup sci.engr.mech 28887

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hudson wrote:
> 
> Hi,
> 
> So here's the problem...Hot exhaust gases (~500-600 deg F) are impinging
> on an airplane wing (7075 al mostly) causing thermal strains and material
> degradation.  Does anyone have any experience with thermal barrier type
> coatings that could be applied to the wing skin to protect the wing from
> as much damage?  A thermal survey of the area indicates an area about 5
> square feet is too hot.
> 
> Some constraints.  Ideally the skin would remain inspectable and could be
> painted to match the original scheme.  (yes the paint is charred in the
> area).  Skin temperatures are measured at about 180 deg F.  Also it is a
> retrofit to an existing airframe so the coating process should avoid
> dissasembly.
> 
> Does anyone have experience I can draw from solving a similar problem?
> Is there a better place to ask this question?  I've spent a lot more time
> with structural analysis than processes and coatings.
> 
>  thanks in advance,
> 
> -Peter-
> 
> --
>   -------------------------------------------------------------------------
>   |  phudson@rohan.sdsu.edu   | Engaged in constant battle with boredom.  |
>   -------------------------------------------------------------------------
Try Courtaulds Aerospac at (818) 702-7474.  They used to have a product
in their Korotherm product line qualified to McDonnell Douglas
specification MMS 455.  They are thermal barrier coatings (filled with
diomataceous (sp?) earth) that will reduce heat transfer.
There are other, such as microballoon filled resins that could coat the
inner surface.
Dave

To anyone knowledgible about automotive weights,
I am a fourth year aerospace engineering student working  on my senior design project. My design team and I are working on a aut
automobile with the ability to fly. Our biggest problem at this moment is in its weight estimate. If anyone out there can give 
us ideas on what components like clutchs, transmissions, basic "H-frames", etc. it would be a great help. Also, if anyone out there 
knows of anyone that would be a good contact or help on the automotive side, it would be a great help as well.
Thanks in advance...........................................
                                                                                     Justin Furch
                                                                                     FURCHJ@sluvca.slu.edu

See link to NACE International Free Corrosion Book Contest on Web Site
indicated below. It is the first in a series of drawings that will be
held at the end of each month. To help NACEW make its web site a great
place to visit. The responses will be used to guide NACE International's
ongoing web site development to make it a valuable source for corrosion
related issues and corrosion control information. 
-- 
CLI International, Inc.
The Materials & Corrosion Specialists
http://www.clihouston.com
CLI's New Specialty Equipment Division offers
Equipment backed by service and experience.

someone is able to tell me if the english I.M.E. has a WEB page?

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.

>> 
>> My specs are:
>>         Fluid: Water
>>         Ports: 3/4" NPT
>>         Flow Rate: 0 - 5 GPM
>>         Pressure: 20 - 120 psi (inlet)
>>         Voltage: Any
>>         NO/NC: Either
>> 
	Have you considered a regular domestic heating system
modulating zone valve, like W/R F1361-102 with F19-0097 modulating
motor ?  Or Taco 570 series ?  ( rather than PWM )
Paul
>~~>~~>~~>~~>~~>~~>~~>~~>~~>~~>~~>~~>~~>~~>~~>~~>~~>~~>~~
pjm@pobox.com 
My personal WWW site is at  http://www.pobox.com/~pjm
The Sci.Engr.Heat-Vent-AC FAQ is at http://www.elitesoft.com/sci.hvac/ 

>rls2222@internetland.net (Sam King) wrote:
>I have picked up bits & pieces about the job title for one who does drafting.  Some stand by the longtime 
>term of draftsman, while others object.  In recent years, we have always called the drafters, which has 
>drawn (no pun intended) no complaints, but what about some of the job titles in the surveying profession?
>Are rodmen & chainmen now rodders & chainer?  Are instrumentmen now instrumentors?  I have tried to use 
>the term Surveyor's Assistant, but that is a catch all phrase, that really doesn't define the specific 
>duties of the job, like the old titles do.  What do you think?
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!)
....John H.

In article <329B292E.13DF@uiuc.edu>, whitchur@uiuc.edu says...
>
>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
Your idea is common to pneumatic system because ON-OFF valves are much 
cheaper than proportional valves. 
When an ON-OFF valve is controlled with pulse-width modulation, the average 
pressure and fluid flow rate is the function of the Duty-Cycle. In an ON-OFF 
valve the flow of fluid composed of pulses of fluid flow at a specified 
frequency. The valve's orifice is fixed and the average flow is controlled 
by the Duty-Cycle. It is different from a proportional/linear valve where 
the valve orifice that controls the fluid flow rate is changed gradually. 
However, in hydraulic systems it is not so common because every opening or 
closing of the valve creates a shock wave in the fluid, causing vibrations 
in the system and demands special attention to avoid braking of tubes and 
parts due to these shocks. 

>In article <329B292E.13DF@uiuc.edu>, "Michael R. Whitchurch"  says:
>>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.
      You can actually get servovalves that work that way from 
Dynamic Valves, Inc., Palo Alto, CA, but they're generally used for
controlling hydraulic equipment and are very expensive.  If you don't
need millisecond-range operating response, go with a standard
motor-driven valve operator.
					John Nagle

In article <57hb5m$8p5@whitbeck.ncl.ac.uk>, p.g.dickinson@ncl.ac.uk says...
>
>Could someone recommend a good reference on aerodynamic heating.
>I am currently testing a high speed rotor with a maximum peripheral
>speed of 500 m/s. We are seeing significant increases in rotor temperature
>at speeds well below the maximum speed.
>
>Thanks
>
>Phil Dickinson
Do you aware that the blade tip and the outer part of it are moving at 
supersonic velocity while the inner part is is moving at subsonic speed. As 
far as I rememeber the prefered blade profile for supersonic is a diamond 
shape because of the shock waves at supersonic speed, while for subsonic 
blade the prefered profile is of a smooth type such as NACA or symerical 
etc. 
I was graduated as an aeronautic engineer at 1972 and since than I didn't 
actually worked in this field. However I work as design/development enginner 
in the aerospace field. Therefore forgive me if I am not completely correct. 
Anyway, I think you should consult a specialist, you can try at the 
university.