What is the temp of this? I need an equation.
What is the temp of this? I need an equation.
(OP)
Hi everyone, and thanks for looking at my problem here.
Please view attached pic which shows two bodies sitting at a distance "R" from eachother, first the rectangle is at 100C degrees and the circle is unknown, my question is there an equation that will help me find the temp. of the circle as a function of "R"?
Thanks
A
Please view attached pic which shows two bodies sitting at a distance "R" from eachother, first the rectangle is at 100C degrees and the circle is unknown, my question is there an equation that will help me find the temp. of the circle as a function of "R"?
Thanks
A





RE: What is the temp of this? I need an equation.
David
RE: What is the temp of this? I need an equation.
Yes, there are lots of them, start here:
http://e
TTFN
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RE: What is the temp of this? I need an equation.
its actualy neither high school or college, its a problem that iam facing at work, i have these two bodies that iam trying to find a relationship between them in a function of thier distance from eachother. there is air between them so they are in conviction if u think about it, however, the conviction effect is so minimal due to the low air velocity however, radiation is what's really effecting it. anythoughts/
Thanks
RE: What is the temp of this? I need an equation.
Given the physical properties and dimensions, this is doable, altough could get tedious.
Jack
Jack M. Kleinfeld, P.E. Kleinfeld Technical Services, Inc.
Infrared Thermography, Finite Element Analysis, Process Engineering
www.KleinfeldTechnical.com
RE: What is the temp of this? I need an equation.
If R is sufficiently small, you get direct conduction. A slightly larger R results in some mutual convection. Only beyond those two conditions would you be safe in ignoring convection transport to the second object.
However, depending on the material of heated part, you can get sufficient convection cooling to change the radiated energy, so CAVEATs abound
Furthermore, you have not specified what the boundaries of this system are, how far away they are, etc.
TTFN
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RE: What is the temp of this? I need an equation.
In terms of boundry conditions. imagine if the circle is sitting inside of a furnace, where the rectangle is a huge heat sink, and the temperature is always constant at that surface. The circle would be your temperature sensor here. there is no air movement iside of that furnace, thus in my opinion convection can be voided.
thanks for ur help guys, let me know what u think of the above.
RE: What is the temp of this? I need an equation.
You really need to tell us more.
What approximate distances are involved, what sizes. What temperatures are we dealing with? You say the circle is in the furnace and the rectangle is a heat sink. Then you say that the temperature of the rectangle is too high to deal with.
What type of access is there? Measurements can be made from outside, perhaps.
Jack
Jack M. Kleinfeld, P.E. Kleinfeld Technical Services, Inc.
Infrared Thermography, Finite Element Analysis, Process Engineering
www.KleinfeldTechnical.com
RE: What is the temp of this? I need an equation.
Good luck!
Tobalcane
"If you avoid failure, you also avoid success."
RE: What is the temp of this? I need an equation.
• The rectangle is a furnace (hot plate, heat source....etc ), I threw in the 100 C as an example but in fact it's around 400C degrees.
• The circle is suppose to be my temperature sensor.
• The distance between the rectangle and the circle (my temp. sensor) varies between 2mm-20mm.
What I am basically trying to do, is place a sensor above the rectangle where the heat is coming from, and based on the readings signal that I receive from the temperature sensor, I could then calculate how far they are apart. Unfortunately, I can't physically go in and measure this distance due to the high temperatures, so I thought this would be an alternative method measuring that distance "R".
Thanks,
RE: What is the temp of this? I need an equation.
Your distances are NOT so large as to be able to neglect convection.
I am sure that there are physical methods to measure the distances.
Jack
Jack M. Kleinfeld, P.E. Kleinfeld Technical Services, Inc.
Infrared Thermography, Finite Element Analysis, Process Engineering
www.KleinfeldTechnical.com
RE: What is the temp of this? I need an equation.
What exactly is the intent? What difference does it make what the distance to the sensor is? If the intent to "calibrate" the sensor, then you're using the wrong sensor. Perhaps an infrared pyrometer would be more appropriate.
I recommend that you explain what you're trying to accomplish, and maybe, there'll be a more direct solution to the actual problem, rather than to deal with your point solution.
TTFN
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RE: What is the temp of this? I need an equation.
Thanks
RE: What is the temp of this? I need an equation.
Tobalcane
"If you avoid failure, you also avoid success."
RE: What is the temp of this? I need an equation.
> laser on fiber-optic?
> proximity sensor?
TTFN
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RE: What is the temp of this? I need an equation.
There are numerous types of instruments that can measure distances
RE: What is the temp of this? I need an equation.
Thank you much for all of ur comments but due to the confidentiality of this project, i am unable to disclose more info on this type of project, however, i could tell u that a temp. sensor is very easy to find and use for appl;ications that run at or around 500-600 C, thus i was thinking if i use a temp. sensor to measure the temperature and based on that I could calculate the distance then it would help me avoid using proximaty sensors.
thanks
RE: What is the temp of this? I need an equation.
RE: What is the temp of this? I need an equation.
If radiation between the two is a concern - place a plate of reflective (bright) metal between the two and separate them thermodynamically. If one has to retain heat that is being to the second - same solution. If one is heating up the second too much so the second is being damaged in some way - run them at two different shifts, or in two different batches, or with a second pice of the same type so both of the same parts get the same treatment with no loss of production time.
Solve the problem, don't try to spend a lot of time calculating something you can measure. You claim that measuring temperature with a probe is simple, and maintaining temperature (of the parts) is what you need to do. These is little else that needs to be "calculated" - when the absolute best you can theorectically calculate for a perfect part in a perfect world in a perfect furnace is - at best - merely an approximation of the "real temperature" that you should measure "for real" .
RE: What is the temp of this? I need an equation.
In all your postings, you've yet to actually specify the accuracy and range of the distance measurements you apparently want. Until you do so, you're not going to get much in the way of meaningful answers.
TTFN
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