| Abstrakt: |
Shale is a sedimentary rock that comprises clay minerals in different proportion. These clay minerals tend to swell when they come in contact with water-based drilling fluid (WBDF); as a result, severe wellbore instability problems develop, which compromises the integrity of the wellbore. In order to find the shale swelling behavior, various researchers have worked on different modeling techniques. Of all the approaches, very recently our group formulated a scaling swelling model to validate the swelling results obtained from linear dynamic swell-meter (LDSM). However, splitting of the dataset at the end of the steeper slope is the complexity associated with scaling swelling model. Hence, to resolve this challenge, an alternative approach was proposed which comprises logarithmic function. Certainly, the use of this operator makes the scaling swelling equation more useful, as it eliminates the splitting part of the swelling dataset. The new approach was compared with scaling swelling model that was not split at the end of the steeper slope. It was observed that for scaling swelling model, the percentage of statistical error sources was almost thrice of what the new approach produces. Moreover, during analysis of variance (ANOVA) it was observed that the variance of LDSM data was similar to the variance of new model, while the previous scaling swelling model shows higher dispersion with a larger value of variance. Conversely, when the splitting was performed, the new approach and scaling swelling model behave almost in a similar manner. In addition, in both the cases the final swelling result was 10.77%, which is almost similar to the experimental LDSM result. This shows that the new approach is extremely efficient in validating the LDSM experimental results, as the intricacies related with the splitting of the dataset are removed. [ABSTRACT FROM AUTHOR] |
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