Page tree

Versions Compared

Key

  • This line was added.
  • This line was removed.
  • Formatting was changed.

...

LaTeX Math Inline
bodyT_e(t, l)

along-hole geothermal temperature profile

Inputs

LaTeX Math Inline
bodyt

Astronomic time



LaTeX Math Inline
bodyl

wellbore trajectory Measured Depth with reference to Earth's surface (

LaTeX Math Inline
bodyl=0
)



LaTeX Math Inline
bodyz(l)

Pipeline trajectory TVDss
wellbore trajectory True Vertical Depth Sub-Sea (TVDss)

LaTeX Math Inline
bodyj_z

True vertical component of

Regional

regional Earth's heat flux

(usually 

LaTeX Math Inline
body--uriencoded--j_z = 25 \div 55 \ mW/m%5e2
)

...





where

...


LaTeX Math Inline
bodyT_{srf}

Annual average surface temperature based on weather reports

LaTeX Math Inline
bodyT_A

Annual average surface temperature variation based on weather reports

LaTeX Math Inline
bodyA_T

Period of annual temperature variation cycle:

LaTeX Math Inline
body--uriencoded--A_T = 1 \, %7B\rm year%7D

LaTeX Math Inline
body\delta t_A

Time moment of seasonal highest temperature with respect to January 1

LaTeX Math Inline
bodya_e

Rock thermal diffusivity



Assumptions




Equations

Below Neutral Temperature LayerAbove Neutral Temperature Layer
Below Neutral Temperature LayerAbove Neutral Temperature Layer
LaTeX Math Block
anchorT_g
alignmentleft
T_g(l) = T_n + \int_{z_n}^z G_T(z) dz
LaTeX Math Block
anchorT_z
alignmentleft
T(t, z) = T_s + \frac{j_z}{\lambda_e} (z-z_s) + T_Y(t, z) + T_D(t, z)
LaTeX Math Block
anchorG_T
alignmentleft
G_T(z) =\frac{d T_g}{d z}= \frac{j_z}{\lambda_e}


LaTeX Math Block
anchorT_zg
alignmentleft
T_Ag(t,zl) = \delta T_An + \, \exp \left[ \, {(z_s-z}) \sqrt{\frac{\pi}{a_e \, A_T}} \, \right] \, \cos \left[  \, 2 \pi \frac{t - \delta t_A}{A_T} + (z_s -z) \sqrt {\frac{\pi}{a_e \, A_T}} \, \right]int_{z_n}^z G_T(z) dz



LaTeX Math Block
anchorT_z
alignmentleft
T(t, z) = T_s + \frac{j_z}{\lambda_e} (z-z_s) + T_Y(t, z) + T_D(t, z)



LaTeX Math Block
anchorG_T
alignmentleft
G_T(z) =\frac{d T_g}{d z}= \frac{j_z}{\lambda_e}



LaTeX Math Block
anchorT_z
alignmentleft
T_DA(t,z) = \delta T_DA \, \exp \left[ \, {(z_s-z}) \sqrt{\frac{\pi}{a_e \, A_DT}} \, \right] \, \cos \left[  \, 2 \pi \frac{t - \delta t_DA}{DA_T} + (z_s -z) \sqrt {\frac{\pi}{a_e \, DA_T}} \, \right]

...




LaTeX Math Block

где

anchorT_z
alignmentleft
T_D(t,z) = \delta T_D \, \exp \left[ \, {(z_s-z}) \sqrt{\frac{\pi}{a_e \, A_D}} \, \right] \, \cos \left[  \, 2 \pi \frac{t - \delta t_D}{D_T} + (z_s -z) \sqrt {\frac{\pi}{a_e \, D_T}} \, \right]


where

LaTeX Math Inline
bodyz_s = z(l=0)

TVDss of the Earth's surface in a given location. In case the Earth's surface is at sea level then 

LaTeX Math Inline
bodyz_s = 0

LaTeX Math Inline
bodyz_s

TVDss of the Earth's surface

LaTeX Math Inline
bodyT_{srf}

Annual average surface temperature based on weather reports

LaTeX Math Inline
bodyT_A

Annual average surface temperature variation based on weather reports

LaTeX Math Inline
bodyA_T

Period of annual temperature variation cycle:

LaTeX Math Inline
body--uriencoded--A_T = 1 \, %7B\rm year%7D
)

LaTeX Math Inline
body\delta t_A

Temperature variation cycle shift (time moment of minimal temperature with respect to astronomic midnight 0:00)

LaTeX Math Inline
bodya_e = \frac{\lambda_e}{\rho_e \, c_e}

Rock temperature conductivity

LaTeX Math Inline
body\rho_e

Rock density

LaTeX Unit
bodyc_e

Rock specific volumetric heat capacity at constant pressure

See Also

...

Geology / Geothermal Temperature Profile

...