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Heat Transfer

Posted 2016年10月22日 GMT-4 15:50 Version 4.4 4 Replies

Sultan Mahmud
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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 2016年10月30日 GMT-4 10:57
Lasse Murtomäki
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Posted: 8 years ago 2016年10月23日 GMT-4 04:19

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
Sultan Mahmud
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Posted: 8 years ago 2016年10月29日 GMT-4 10:22
Thanks sir
Thanks sir
Sultan Mahmud
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Posted: 8 years ago 2016年10月29日 GMT-4 11:31
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 ??
Lasse Murtomäki
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Posted: 8 years ago 2016年10月30日 GMT-4 10:57
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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