| This paper based on systematic analyzing and indepth surveying the present situation of researching at home and abroad, integrated applied the knowledge of surface chemistry, rheology, fluid mechanics, linear elastic fracture mechanics, heat transfer, differential equation, optimization theory, computational mathematics, etc., carried on research work in the aspects of surfactant fracturing fluid mechanics, fracturing optimum design, fracturing analyzing and evaluating, achieved the following research findings:(l)Adopted a great variety of experimental media, such as transmission electron and scanning electron microscope etc, integrated with the basic theory of surfactant solution, by means of analyzing the relevance of surfactant between inhesion and extrinsic, macroscopic and microscopic, investigated the gel forming mechanism and the gel breaking mechanism.(2)Put forward the mechanism that surfactant fracturing fluid is mainly elastic sand carry, and the method of using suspending shear force indicating the prop-carrying capacity of surfactant.(3)Investigated fracture design model and approach, that include fracture three-dimensional extension model, proppant migration distribution model, numerical model of temperature field, method for optimal design of fracture parameter etc.. Among others, multilayer and heterogeneity of formation were considered in the newly fracture three-dimensional extension model, therefore it could simulate variety affect, such as multilayer formation thickness, ground stress, rock mechanics parameter (like Poisson ratio, elasticity modulus, fracture toughness), apply to a variety of stress distribution mode and extension before and after fracture breaking through layer.(4)Improved concept for fracture optimal design, that is to say according to formation condition, for purpose of optimum fracture effect, by means of continually and automatically adjust volume of fracturing fluid in each block, displacement, sand proportion in the surface, proppant type, etc., designing optimum operational scheme which could arrive optimum fracture effect and no sand plug.(5)According to flow mechanism of fractured well, considering the process of the return flow of variable flow rate, well bore storage, contamination on fracture surface, and multi-boundary condition, etc., instituted percolation mathematical model between formation and fracture system in phase of the return flow, and put in the solution of the percolation mathematical model. The solution for problem of flow rate is both enhancing the accuracy of calculation and increasing calculation speed by more than 1000 times . It can meet the needs of real-time computation and fast response.(6)Put forward the automatic match method of inversion parameters of the return flow, i.e. the numerical calculation method of comprehensive application stepwise linear least square method and constraint variable measure method.(7)Optimized fracturing design software and inversion parameters software of the return flow has researched. It followed the principle of taking data as the center and can see the operation as main body. They are provided with function strong, operation convenience, calculation way stability and credibility, run speed quick, interface amity, result reasonable, commercialize degree high. The applied software carried on a great deal of literature contrast, theories verification and example analysis. That explained the credibility and the applicability of the software and express the software can satisfy the demand of actual problem.(8)Researched surfactant fracturing fluid has applied 38 wells which locate 21# well area of Shinan,4# well area of Shinan and Mobei.These areas are water sensitive, formation pressure coefficient low. Applied instance indicate, surfactant fracturing fluid is provided with performance stability, operation convenience, carry sand ability strong, increase production effect well, especially adapt to apply at oil field of low pressure and low permeability. In 2003,3 well areas increaseed the oil accumulation 60917t, created theprofits 58635810RMB, input output ratio reached 1: 4.49. It provided the technique guarantee for high efficiency recovery of oil field of low porosity and low permeability and water sensitivity.Returns of this paper in fracturing fluid was affluent in knowledge system of surface chemistry, rheology and hydrafrac engineering. It is good for technique popularizing and development new system of surfactant fracturing fluid. It is hopeful to develop new domain of environmental protection type fracturing fluid. Returns of this paper in fracturing design not only developed and perfected existing three dimensional fracture extend models, and can simulate extend of fracture height more finely, most of all it is importance meaning for fracture increase production reconstruct to oil and gas reservoir that have basal water or top water. Returns of this paper in fracture analyse evaluating technique formed new technique of analyse of fracturing fluid back process and inversion fracture parameter. Relational fracturing parameter can be realize fast and accurate by this technique.It attain the purpose of estimate fracture effect fast and accurate. After research result is transformed productivity.it can part replace buildup of pressure testing of fracture well, reduce testing expenses, make fracturing well produce in advance.
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