Page tree

Versions Compared

Key

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

...

LaTeX Math Block
anchorCase2_PSS
alignmentleft
\delta q_1 / \delta q_2 = f_{21} =  \frac{V_{\phi, 2}}{ V_{\phi, 1}} = \rm const

while the response delay in time becomes irrelevant at long terms of the conventional production analysis.


Expand
titleDerivation


Panel
borderColorwheat
bgColormintcream
borderWidth7

For the finite-volume reservoir 

LaTeX Math Inline
body V_{\phi,1} \leq V_{\phi,2} < \infty
 the DTR and CTR are both going through the PSS flow regime at late transient times:


LaTeX Math Block
anchorCase2_PSS_p11
alignmentleft
p_{u,\rm 11}(t \rightarrow \infty) \rightarrow \frac{t}{c_t V_{\phi, 1}}



LaTeX Math Block
anchorCase2_PSS_p21
alignmentleft
p_{u,\rm 21}(t \rightarrow \infty) \rightarrow \frac{t}{c_t V_{\phi,2}}


where

LaTeX Math Inline
bodyc_t

average drain-area  total compressibility of formation within  

LaTeX Math Inline
bodyV_{\phi,1}
 which is jointly drained by  producer W1 and injector W2 

Substituting 

LaTeX Math Block Reference
anchorCase2_PSS_p11
 and 
LaTeX Math Block Reference
anchorCase2_PSS_p21
 in 
LaTeX Math Block Reference
anchorCase2
 one arrives to
LaTeX Math Block Reference
anchorCase2_PSS
.



In case when injector W2 supports only one producer W1 then

LaTeX Math Inline
bodyV_{\phi, 2} = V_{\phi, 1}
 and 
LaTeX Math Inline
body\delta q_1 = \delta q_2
, which means that producer W1 with constant BHP and finite-reservoir volume will eventually vary its rate at the same volume as injector W(the response delay in time becomes irrelevant at long terms of the conventional production analysis)2.



If pressure in producer W1 is supported by several injectors 

LaTeX Math Inline
bodyN_{\rm inj} > 1
then over a long period of time one can assume:

...