In case of dual-barrier well completion with flowing fluid in the annulus (see Fig. 3) the HTC is defined by the following equation:
\frac{1}{ d_{ti} \, U} = \frac{1}{d_{ti} \, U_{ti}} + \frac{1}{\lambda_t} \, \ln \frac{d_t}{d_{ti}} + + \frac{1}{\lambda_{a, \rm eff}} \ln \frac{d_{ci}}{d_t} + \frac{1}{\lambda_c} \ln \frac{d_c}{d_{ci}} + \frac{1}{\lambda_{cem}} \ln \frac{d_w}{d_c} |
where
outer radius of tubing (with outer radius ) | ||
inner diameter of the tubing (with inner radius ) | ||
tubing wall thickness | ||
outer radius of casing (with outer radius ) | ||
inner diameter of the casing (with inner radius ) | ||
casing wall thickness | ||
thermal conductivity of tubing material | ||
thermal conductivity of fluid moving through the tubing | ||
effective thermal conductivity of the annulus | ||
Natural Convection Heat Transfer Multiplier | ||
thermal conductivity of fluid in the annulus | ||
heat transfer coefficient (HTC) |
Physics / Thermodynamics / Heat Transfer / Heat Transfer Coefficient (HTC) / Heat Transfer Coefficient (HTC) @model
[ Thermal conductivity ] [ Nusselt number (Nu) ]