Gaussian formulation based correlation for Dietz shape factor

Abstract

The traditional semi-steady state inflow equation involves Dietz shape factor which depends on reservoir geometry and well location in that geometry. The actual Dietz shape factors are computed utilizing the equation based on the method of images. In this respect, the methodology for the calculation of the Dietz shape factor by means of the method of images is presented. The correlation developed for the estimation of Dietz shape factor is based on the Gaussian function. The correlation is valid for the homogeneous rectangular reservoir areas with aspect ratios in the range from 2 to 5. It is observed that the absolute difference from the actual logarithm of Dietz shape factor is less than 0.16 and 0.43 for the ratio of well coordinates to corresponding block lengths in the range from 0.2 to 0.8 and in the range from 0.15 to 0.85, respectively. The study additionally involves the comparison with the results of the previous simple analytical solution developed for prediction of the Dietz shape factor. The comparison reveals slight improvements in estimation of the Dietz shape factor by means of the developed correlation for well locations close to the borders of the reservoir area.