analysis of transient heat conduction in different geometries - ethesis ...
analysis of transient heat conduction in different geometries - ethesis ...
analysis of transient heat conduction in different geometries - ethesis ...
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Differentiat<strong>in</strong>g the above equation with respect to x we get<br />
Apply<strong>in</strong>g first boundary condition we have<br />
∂ θ<br />
= a1+ 2a2x<br />
∂ x<br />
a1+ 2a2x= 0<br />
(3.112)<br />
Thus<br />
a 1 = 0<br />
(3.113)<br />
Apply<strong>in</strong>g second boundary condition we have<br />
Thus<br />
a + 2a<br />
=−Bθ<br />
1 2<br />
a<br />
2<br />
Bθ<br />
=−<br />
2<br />
We can also write the second boundary condition as<br />
Us<strong>in</strong>g the above expression we have<br />
Average temperature for long slab can be written as<br />
37<br />
(3.114)<br />
(3.115)<br />
∂ θ<br />
=− B( a0 + a1+ a2)<br />
∂ x<br />
(3.116)<br />
⎛ B ⎞<br />
a0 = θ ⎜1+ ⎟<br />
⎝ 2 ⎠ (3.117)<br />
1<br />
0 dx<br />
θ θ = ∫<br />
Substitut<strong>in</strong>g the value <strong>of</strong> θ and <strong>in</strong>tegrat<strong>in</strong>g we have<br />
Bθ<br />
θ = θ +<br />
3<br />
Integrat<strong>in</strong>g non-dimensional govern<strong>in</strong>g equation we have<br />
(3.118)