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Dynamic Data Analysis – v5.12.01 - © KAPPA 1988-2017
Chapte
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2.H.2
Effect of ‘unknown’ parameters
2.H.2.a
Wellbore storage
The figure below presents the response with all default parameters except for the wellbore
storage. Values for C are 0
.001, 0.003, 0.01, 0.03
and 0.1 (stb/psi).
The value of C has a major effect, which is actually exaggerated by the logarithmic time scale.
You can see on the linear history plot that all responses seem to be the same, however.
Infinite Acting Radial Flow: When the influence of wellbore storage is over all responses merge
together, both in terms of pressure and derivative. Wellbore storage does not play any role
except that it masks infinite acting radial flow on a time that is proportional to the value of C.
PSS: Wellbore storage does not affect the late time response.
Fig. 2.H.3 – Effect of wellbore storage, loglog plot
Fig. 2.H.4 – Effect of wellbore storage, semilog and history plot plot