Study On Pressure-production Dynamic Model And Method Of Tight Oil Reservoirs With Fractured Horizontal Well

China's tight oil resources are abundant and widely distributed,and have become an important resource to replace China's oil production.However,most of the tight reservoirs in China are continental deposits with complex sedimentary environments and diverse genesis.Different types of tight reservoirs have great differences.Because of their small roar throat and natural fracture development,and poor permeability,largescale fracturing is needed before production.Complex fracture network is formed after fracturing,and there exists cross between reformed and unreformed reservoirs.The seepage law is more complex,which makes it more difficult to analyze the dynamic development of pressure and production.The study of large-scale fracturing pressure and production dynamic model of horizontal wells in tight reservoirs plays an important role in guiding the efficient development of tight reservoirs.This paper mainly completes the following work and achieves a series of important results:(1)Through the literature investigation and Research on the physical properties of tight reservoirs,it is concluded that large-scale fracturing of horizontal wells is the key technology for effective development of tight reservoirs.Based on the relationship between physical properties and compressibility of tight reservoirs,well spacing and fracturing interval,four kinds of seepage physical models are put forward,which can cover all situations.(2)According to the main percolation characteristics of tight reservoirs and combined with the four seepage physical models proposed,four horizontal well test models for fracturing in tight reservoirs,including bilinear flow,combined bilinear flow,trilinear flow and five-zone multilinear flow,are established.The typical well test charts of the four models are obtained,and the well spacing and interval are analyzed.The influence of spacing,fracture bandwidth,reservoir physical properties in different regions,such as dual media parameters,on well test curve shape is studied.These studies provide theoretical support for fracturing well test analysis of horizontal wells in tight reservoirs.(3)On the basis of four well test models,the dimensionless pressure formulas of four models for boundary control flow are fitted.Using the method of establishing Blasingame decline curve,the dynamic analysis models of Blasingame production of four models are established,the analysis chart of Blasingame curve is drawn,and the calculation methods of reservoir parameters and dynamic reserves are established.(4)The software of tight oil well testing and production analysis optimization is compiled in C# language,including the functions of fracturing horizontal well testing analysis,production performance analysis,production decline analysis and production prediction.These results provide theoretical and technical support for effective development of tight reservoirs.