Control Seam High Hydraulic Fracturing Artificial Interlayer Thickness Optimal Design Method

The technology of using artificial barrier to control high in Hydraulic fracturing, been a crucial technology for special oil-gas reservoir, has been applied widely in the oil field. Restricted by the existing model and software, the optimum height of artificial barrier and the position of pave are difficulty to be accurately designed, and the amount used of separant is impassable calculated. This leads to overabundance or inadequateness for the amount of separant. Overabundance leads to thick artificial barrier, which both harmed the fracture flow capacity and cause a high cost. Inadequateness leads to thin artificial barrier, which cannot form a low permeable or impermeable artificial barrier, which only slightly can change the flowing pressure distribution in the fracture vertically, and which cannot reduce the difference between flowing pressure and the stress. Moreover, the artificial barrier cannot achieve the function of the diverter, and cannot make afterwards carrying fluid transfers flow horizontal, and make the projection less efficiency.At present, in this technology has not a quantitive model to portray the artificial barrier pressure drop, best position of pave, thickness and the best amount of used. Therefore, this thesis system analys the domestic and foreign artificial barrier control high-tech's principle, the craft achievements. This thesis also classifies control high-tech. basing on predecessor's research, the author by using improved three-dimensional model and the temperature model analysis the rule of the fracture extend. Thus the author obtained the fracture parameter, temperature, speed of flow in the fracture, and so on. Combining transfusion mechanics, the author regard permeation of the artificial barrier as the function of the pore size and the pore configuration distribution, and then, the permeation is decided from the geometry and the transfusion mechanics. Referencing the appraisal method of the flow capacity, the author establish a formula of artificial barrier pressure drop and thickness, and a formula of the best thickness of the artificial barrier for pressure in the fracture, the artificial barrier permeation and the smallest stress of barrier. The author listed the relations between the thickness of the pave and the fracture high in the direction of the fracture length. At the same time, by applying the optimization, the author has designed the optimization model of artificial barrier's high, and has quantified the best delivery rate and critical amount of the separant when it is being transported. After simulated it by computer, the author obtained following results: temperature distributing in the fracture at any time; the rule of the pressure drop in artificial barrier; best thickness of artificial barrier; the best delivery rate in the separant transporting...