Phase distribution and intrapore salt exchange during drilling mud invasion of an oil- and gas-bearing formation

Analysis of a Mathematical Model for Drilling System With Reverse Air Circulation by Using the ANN-BHCS Technique

“…The efficiency o f A NN-BHCS a lgorithm i s obvious from convergence analysis of values of performance metrics which are given in Tables (5,10,15,20,25) and Figs. (7,10,13,16) and (19). The results show that the algorithm can efficiently minimize the fitness function and obtains the best solution as more than 90% values of the fitness function and performance metrics are less than E − 03.…”

“…Histograms and box plots of the values of the fitness function and performance metrics are given in Figure (16). Histogram of the fitness values shows that more than 80% of the values are less than or equal to E −03 and box plot shows that more than 75% of the values are in the range E − 03 to E − 08.…”

Damage Mechanism of Oil-Based Drilling Fluid Flow in Seepage Channels for Fractured Tight Sandstone Gas Reservoirs

“…Presently, the research on formation damage caused by OBDF has mainly focused on solid phase invasions, wettability changes, and oil traps and there are relatively few studies on why OBDF causes these damages. Cui et al [4] studied the damage of solid phase invasions to reservoirs, while Korsakova et al [5] studied the phase distribution and salt exchanges in boreholes during drilling fluid invasion in oil and gas reservoirs. Rong and others [6] used new methods to study the wettability reversal caused by OBDF, Skalli and others [7] studied the wettability effect of surfactants on surface and core in OBDF, and Yan and Sharma [8] studied the wettability change caused by OBDF.…”