Thermal resistance offered by the material in layer 2 along the flow path q1.

Symbol
$R_{\mathrm{q21}}$
Unit
K.m/W
Formulae
$\frac{\ln{\left (\frac{2}{D_{\mathrm{o}}} \left(C_{3} \left(\frac{c_{\mathrm{T}}}{2} + \frac{d_{\mathrm{T}}}{2} - s_{\mathrm{3}}\right) + s_{\mathrm{T}}\right) \right )}}{k_{\mathrm{3}} \left(\operatorname{atan}{\left (\frac{s_{\mathrm{3}}}{s_{\mathrm{T}}} \right )} + \operatorname{atan}{\left (\frac{s_{\mathrm{4}}}{s_{\mathrm{T}}} \right )}\right)}$
Related
$c_{\mathrm{T}}$
$k_{\mathrm{3}}$
$s_{\mathrm{3}}$
$s_{\mathrm{4}}$
Used in
$R_{\mathrm{q2}}$
Resistance 2 [K.m/W]