Heating solid to high temperature

[phyzzy_physh]

Hi,

I want to electrically heat a uniform block of a known material to a high temperature (about 2000 K). I want to get a rough idea of how much electrical energy I need to supply to raise the material to this temperature so as to gauge what apparatus I will need. How would I go about this?

Any help would be much appreciated :)

Thanks

Fish

 

[nasu]

At equilibrium the power radiated should be equal to the electrical power input.
The power radiated is given by Stefan-Boltzmann law.
P_rad=Sigma*T^4*Area
Where Sigma is the S-B constant and "Area" is the surface area of the object.
If the object is not a black body you need to multiply by a correction factor.
It will give you a minimum estimate because heat will be also lost by convection and air conduction but I suppose that at 2000 degrees the radiation will be the main factor (if the object is in air and not in some liquid).

 

[Mapes]

At equilibrium the power radiated should be equal to the electrical power input.

This will give an estimate of the steady state power P required once the object is heated. To estimate the total energy needed, multiply the object's heat capacity C by the temperature increase $\Delta T$ (assuming no phase change occurs). The energy required for heating the object in time t will be between $C\Delta T$ and $C\Delta T+Pt$. More exact estimates are possible, but this gives a good first approximation.

 

[Dadface]

Hello fish, from your post I am imagining a largish metal block and difficulties in heating this electrically .Could you not use something like a furnace?If the shape,size and nature of the metal are irrelevant you could use an ordinary filament light bulb.In normal use the filament can reach temperatures in excess of 2000 degrees.

 

[phyzzy_physh]

Hi guys,

Thanks for your replies; I only wanted a quick rough idea of how to work this out so they were really helpful.

Dadface, the furnace is an option but I wanted to work this out before commiting to anything. :)

Thanks again guys.

Fish