What is Thermal conductivity: Definition and 184 Discussions
The thermal conductivity of a material is a measure of its ability to conduct heat. It is commonly denoted by
k
{\displaystyle k}
,
λ
{\displaystyle \lambda }
, or
κ
{\displaystyle \kappa }
.
Heat transfer occurs at a lower rate in materials of low thermal conductivity than in materials of high thermal conductivity. For instance, metals typically have high thermal conductivity and are very efficient at conducting heat, while the opposite is true for insulating materials like Styrofoam. Correspondingly, materials of high thermal conductivity are widely used in heat sink applications, and materials of low thermal conductivity are used as thermal insulation. The reciprocal of thermal conductivity is called thermal resistivity.
The defining equation for thermal conductivity is
q
=
−
k
∇
T
{\displaystyle \mathbf {q} =-k\nabla T}
, where
q
{\displaystyle \mathbf {q} }
is the heat flux,
k
{\displaystyle k}
is the thermal conductivity, and
∇
T
{\displaystyle \nabla T}
is the temperature gradient. This is known as Fourier's Law for heat conduction. Although commonly expressed as a scalar, the most general form of thermal conductivity is a second-rank tensor. However, the tensorial description only becomes necessary in materials which are anisotropic.
Whats its thermal conductivity compared to copper? (as in x times worse than copper)
also, How electrically insulate is it? I'm looking to see if i can use it to encase an entire motherboard in a giant heat sink for a future project where i want to try and cool the entire motherboard to subzero...
I know k is thermal conductivity but my teacher never told me about effective coefficient of thermal conductivity. I tried googling and found:
$$k_{effective}=\frac{\Sigma{k.A}}{\Sigma A}$$
But I don't know the area to used that information. Is there another approach to do this question?
Thanks
I've tried to explicitly solve the Fourier's equation in cylindrical coordinates but I'm getting some messy integrals which cannot be solved analytically. Additionally my instructor said that there's a neat trick for this problem and it's possible to obtain the answer in a rather elementary...
Good afternoon everyone!
I've learned that thermal conductivity has a form of second-rank tensor. As you know, diagonal components of stress tensor mean normal stress and other components mean shear stress and like that do off-diagonal components of thermal conductivity tensor have some special...
When we measure 'the rate of conduction heat transfer'=Q , we assume that the hot side and the cold side's area are same. But if the both side's area is different to each other, how can i know the rate of conduction heat transfer?
like below figure.
Would you like to help me?? Thanks.
We know that,
Conduction Heat Transfer Q = KA(t2-t1)/thickness
K is the coefficient of thermal conductivity. If T2 = 1020°C and T1= 22°C also consider we know A and thickness value.
K depends on temperature. K varies with temperature. For all the materials we have a tabular data of K for...
Hello,
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Overall thermal conductivity?
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thickness of layer 1= t_1 = 0.004 m
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