The Heat Transfer Coefficient (HTC) of dual-barrier well completion
...
| title | Dual-barrier Completion |
|---|
...
is defined by the following equation:
| LaTeX Math Block |
|---|
|
\frac{1}{ dr_{ti} \, U} = \frac{1}{dr_{ti} \, U_{ti}} + \frac{1}{\lambdar_ t{ti} \, \ln \frac{dU_t} {d_{ti}} +
+ \frac{1}{\lambdad_{a, \rm eff}}ann} \ ln \frac{d, U_{ci}}{d_tann}} +
\frac{1}{\lambdar_ c{ci} \ln \frac{d, U_c} {d_{ci}} + \frac{1}{\lambdar_c \, U_{cem}} \ln \frac{d_w}{d_c} |
where
...
| outer radius of the tubing |
...
...
| inner radius of the tubing |
|
...
...
...
| tubing wall thickness |
| outer radius of the casing |
|
...
| inner radius of the casing |
|
...
...
...
...
...
...
...
...
| wellbore radius by drilling bit |
|
...
...
...
...
...
...
| --uriencoded--\displaystyle U_c = \frac%7B\lambda_c%7D%7Br_%7Bci%7D \cdot \ln (r_c |
|
|
...
...
...
...
...
...
...
...
...
...
...
...
heat transfer coefficient (HTC)
between inner surface of tubing and moving fluid
The equation
| LaTeX Math Block Reference |
|---|
|
can be written explicitly as:| LaTeX Math Block |
|---|
|
\frac{1}{ r_{ti} \, U} = \frac{2}{\lambda \, {\rm Nu}_{ti}} + \frac{1}{\lambda_t} \, \ln \frac{r_t}{r_{ti}}
+ \frac{1}{\lambda_{ann} \, {\rm Nu}_{ann}} +
\frac{1}{\lambda_c} \ln \frac{r_c}{r_{ci}} + \frac{1}{\lambda_{cem}} \ln \frac{r_w}{r_c} |
In case the annulus is filled with stagnant fluid the annulus fluid convection will be natural and the Convection Heat Transfer Multiplier
is a function of Rayleigh number .In case the annulus fluid is moving the annulus fluid convection will be forced and the Convection Heat Transfer Multiplier
can be approximated as:See also
...
Physics / Thermodynamics / Heat Transfer / Heat Transfer Coefficient (HTC) / Heat Transfer Coefficient (HTC) @model
[ Single-barrier well completion Heat Transfer Coefficient @model ]
[ Thermal conductivity ] [ Nusselt number (Nu) ] [ Natural Convection Heat Transfer Multiplier ]
