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Heat Transfer

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I am trying to design a model which will b use for heat transfer .I am trying to design this model in Nanomete Scale (Surface and Rod).Rod i put on the surface and i did simulation but no change in temperature bottom side and top side .First it showed error then i removed error .now how can i get temperature variation??

4 Replies Last Post 30 ott 2016, 10:57 GMT-4

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Posted: 8 years ago 23 ott 2016, 04:19 GMT-4

I am trying to design a model which will b use for heat transfer .I am trying to design this model in Nanomete Scale (Surface and Rod).Rod i put on the surface and i did simulation but no change in temperature bottom side and top side .First it showed error then i removed error .now how can i get temperature variation??


In nanoscale you won't get any temperature differences because heat transfer is so fast. You can compare this with the famous Einstein formula for diffusion length, d ~ sqrt(D*t), i.e. the time in which particle leaps over the distance d is d^2/D. If d = 100 nm and D = 1e-5 cm^2/s, time needed is 10 microsec. Heat transfer is even more efficient, temperature differences disappear in nanoseconds in nanoscale.

BR
Lasse
[QUOTE] I am trying to design a model which will b use for heat transfer .I am trying to design this model in Nanomete Scale (Surface and Rod).Rod i put on the surface and i did simulation but no change in temperature bottom side and top side .First it showed error then i removed error .now how can i get temperature variation?? [/QUOTE] In nanoscale you won't get any temperature differences because heat transfer is so fast. You can compare this with the famous Einstein formula for diffusion length, d ~ sqrt(D*t), i.e. the time in which particle leaps over the distance d is d^2/D. If d = 100 nm and D = 1e-5 cm^2/s, time needed is 10 microsec. Heat transfer is even more efficient, temperature differences disappear in nanoseconds in nanoscale. BR Lasse

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Posted: 8 years ago 29 ott 2016, 10:22 GMT-4
Thanks sir
Thanks sir

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Posted: 8 years ago 29 ott 2016, 11:31 GMT-4
Dear Sir ,
But I want to Nano-Modification to enhance the surface area .how it possible?Is it Possible to make separately surface in nanometer scale and rod will meter scale ??
Dear Sir , But I want to Nano-Modification to enhance the surface area .how it possible?Is it Possible to make separately surface in nanometer scale and rod will meter scale ??

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Posted: 8 years ago 30 ott 2016, 10:57 GMT-4
I do not believe that it is possible, but I am not 100% sure.
I do not believe that it is possible, but I am not 100% sure.

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