Phase shift

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Registration: 26/09/14, 13:57

Phase shift




by Link » 14/05/15, 20:23

Hello,

I wanted to know which formula vs use to calculate the time phase shift of an insulator because by searching the net I found several:

Image


Thanks to those who read the post!
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dedeleco
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by dedeleco » 09/12/15, 15:48

read as well as the links on:
https://fr.wikipedia.org/w/index.php?ti ... =100041470
http://archive.wikiwix.com/cache/?url=h ... 1perio.htm
http://echo.epfl.ch/files/content/sites ... %20sol.pdf

"At the penetration depth, the phase shift is 1 radian or 56,3 ° for an attenuation of the oscillations by 1 / e or by 0,368 "

So well before the phase shift or delay, there is a very strong attenuation of the oscillations this in an infinite medium and a little differently if finished.

Otherwise for a finite medium of thickness, the result of the delay depends on boundary conditions inside and outside (how the heat arrives outside and how it is used inside), often unspecified and implicit differences change the formula, as well as units of angle radians, ° !!


"This penetration length for a typical material with diffusivity of 1 mm2 / s (approximately for clay or earth) is for a period Tp of one second of 0,564mm, to be multiplied by the inverse of the square root of Tp in seconds.

For one day it is root 24x3600 times longer, ie 166mm

For a year with 365 days, it is 365 times the root of the previous one, ie 3,168m and therefore beyond 10 m underground, annual temperature oscillations no longer penetrate. In soil full of humus very rich in plants such as straw, (torchi wall) it can be 3 times less. "

Finally against a heat wave insulating for the winter with immobile air does not protect from a heat wave, because if well insulated, the slightest solar heat overheats !!

To block the heat wave, very low diffusivity is required, obtained by:
alternate an insulating layer with immobile air with a layer of the same thickness of heavy as earth, stone, or other with high thermal capacity !!

A simple rammed earth straw, corresponds to this, isolates and protects from a heat wave with a few tens of cm !!
Last edited by dedeleco the 09 / 12 / 15, 16: 07, 2 edited once.
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The bees disappear pesticide, Roundup, and are killing us slowly. http://www.pollinis.org/petitions/petit ... noides.php
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Obamot
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by Obamot » 09/12/15, 15:53

Yes the theory is beautiful!

In the meantime: please do not hide and answer my simple question (if you can do it):
https://www.econologie.com/forums/stockage-i ... tml#294898
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dedeleco
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by dedeleco » 09/12/15, 16:06

Insulated BBC houses overheated by heat waves are not theory for those affected, any more than pleasant and cool adobe houses !!



And they have nothing to do with bentonite at all on this post trolled by O's insomnia obsessions !!
And O bas mot seems to have irritated skin problems that make it insomniac to get on the buttocks and detoxify with bentonite !!
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Thiazolinones neuro toxic to avoid them being everywhere, madness, killing at least ppm, bacteria and your neurons, which multiplies Alzheimer !!

The bees disappear pesticide, Roundup, and are killing us slowly. http://www.pollinis.org/petitions/petit ... noides.php
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by 1360 » 09/12/15, 19:12

Back Dede ?!

We can say that it is going strong again!

I'm going to laugh, me ...

;)
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Trying too hard to get into the mold, it ends up looking like a pie.
dedeleco
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by dedeleco » 09/12/15, 23:01

1360 wrote:Back Dede ?!

We can say that it is going strong again!

I'm going to laugh, me ...

;)


We are going to reboot dd at high quantum V speed !!
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Thiazolinones neuro toxic to avoid them being everywhere, madness, killing at least ppm, bacteria and your neurons, which multiplies Alzheimer !!

The bees disappear pesticide, Roundup, and are killing us slowly. http://www.pollinis.org/petitions/petit ... noides.php

 


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