The Horner’s improved method applied to analyze pressure curves during wells hydrodynamic testing
The article presents the Horner's updated method to analyze the data of wells hydrodynamic testing, based on special transformation of pressure curves that reduces the time required by the transformed pressure curves to reach the asymptote modes, necessary for these data processing. The method is based on the exact analytical solution of the piezo-conductivity equation considering the action of the "skin factor" and after-inflow effect in the form of an asymptotic series in case of large values of time. In contrast to the Horner’s classical logarithmic derivative method, which in fact uses only the main member of such asymptotic dissection, the proposed method also takes into account the next higher member of the dissection, represented as a certain time-dependent function. The essence of the proposed method lies in exclusion of the asymptotic dissection member from the pressure curve by means of the member’s optimal ratio selection in such a way that the transformed pressure curve should maximally quickly reach the asymptotic mode respective to the main member of the series (the Horner’s solution). Computer calculations show that the application of the proposed method can significantly improve the accuracy of the determination of the bed parameters.