Parameters optimization in deepwater dual-gradient drilling based on downhole separation

WANG Jiangshuai,LI Jun,LIU Gonghui,HUANG Tao,YANG Hongwei

Table 2 The range of drilling parameters under different n values.

n value Separation efficiency Injection volume fraction Density of pure drilling fluid/(kg?m-3) Distance between separator and bit/m Wellhead back pressure/Pa Displacement/ (L?s-1) 5 0.4 [0.30, 0.38] [1 000, 1 200] [100, 500] [0, 2 000 000] [30, 42] 6 0.4 [0.30, 0.40] [1 000, 1 250] [100, 600] [0, 2 500 000] [30, 45] 7 0.4 [0.30, 0.42] [1 000, 1 300] [100, 700] [0, 3 000 000] [30, 48]