Imagine if heat is being generated in a container maintained at atmospheric pressure. will the heat generated inside the container be removed or sucked out of the container if the container is suddenly exposed to vacuum pressure
The generated heat inside the container will trnsfer with minimum flow rate firstly by radiation to the walls of containers and then by convection between the walls and the surroundings if there is no insulator between them.
Heat can flow by conduction and/or convection and/or radiation. If the heat source is under vacuum, heat can still flow by radiation (see the heat of the sun arriving to earth through vacuum (in space) by radiation.
There will be heat flow as there although is no such thing as perfect vacuum. Just think of the thermos we put in hot coffee. It keeps warm for some hours because there are very view particles to carry the heat at the containers boundary by convection. Radiation is no problem to occur. It depends on your containers properties and temperature. So yes you will have mainly radiation, and some convection.
Dear Abhiram Vedala
Heat is possible in vacuums, there is not oddity on that.
Macroscopically, we say that Heat can be transferred by three mechanism: Conduction, Convection and Radiation.
The first two need a material medium to happen. This is to say that, these mechanisms need an atomic (or otherwise; ions, molecules, particles) structure to be transferred trough, since Conduction and Convection is Heat transfered across atoms and molecules.
Radiation is very different, Radiation is EM Energy, which as we know, EM waves doesn't need a material medium to propagate.
So, even if you pull out all the air from a cavity making a vacuum, the EM Energy which was already inside this cavity will not be pulled out as the air is.
So, the atoms and molecules in, and making the air, will be pulled out. And the Thermal Energy corresponding to Conduction and Convection with them. So, Macroscopically: Zero Conduction and Convection Heat transport. But the Heat due to Radiation (Electromagnetic Waves) will still be inside the cavity. So this part of the overal Heat would n't be pulled out.
Now, microscopically: Heat is transported by different particles (now I'm speaking of microscopic particles or even elementary particles).
So, Heat can be transported by electrons, ions, atomic nuclie, by phonons (which are the quantized vibrations of an atomic lattice), or by Photons, which is what light is composed of.
So, in the case of a vacuum, there won't be enough atoms and free electrons for:
i. for Phonons to be created, ii. nor a current of electrons to be created, or any transport current of any particle transporting Energy. So, Electrons, atoms, phonons, all of this that contribuite to the macroscopic phenomena of Conduction and Convection will be pulled out with the air and the medium which were there before applying the vacuum.
But not Photons. Photons cannot be affected like that by this external Force (or Pressure). So, viewed from a microscopic approach, it can also be seen that the EM Energy (which is also Heat) contained in the photons which were inside the cavity before the suction remains.
Regards !
Franklin Uriel Parás Hernández SO i can induce a desiccant into the system that can act as a carrier, will the be effective? i have tried to look into gaseous desiccants and heat absorbents that can be induced into the system which can give me the desired result.
Abhiram Vedala :
What do you mean with "a desiccant" , and what do you mean with "that can act as a carrier" ?
Best Regards ! :)
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https://www.quora.com/What-is-vacuum-pressure
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