Solution Of Seepage Equation With Start-up Pressure Gradient

As China’s oil drilling, have been detected reserves of low permeability reservoir is moreand more big, and has to dominate the field development in China.So the exploitation of low permeability reservoir needs more technical force, start-uppressure gradient of low permeability reservoir seepage law of studies is the is the key, thestudy of start-up pressure gradient is particularly important Special importance by solvingseepage equation with start-up pressure is more prominent. In this paper, by solving thesingle-phase and two-phase seepage equation with start-up pressure and seepage flowdifferential equation, summed up the impact of start-up pressure and the development indexesand verified First through solving the percolation with start-up pressure equation, therelationship of starting pressure and the development index, such as moisture content,permeability, single well production, formation pressure, velocity, etc., such as start-uppressure gradient and permeability is inversely proportional to the square root and the relationof start-up pressure gradient and oil into inverse relationship, namely the start-up pressuregradient, the greater the daily oil production and cumulative oil production.In low permeable oil fields, with the increase of moisture content, formation pressurebegan to slowly increase finally becomes smooth, gradually is greater than the originalformation pressure In low permeable oil fields, therefore, if the formation energy is notenough, the need for advanced water injection to complement formation energy, so you canmaintain high formation pressure, but the local layer arrived at high water-cut stage, theformation pressure values are drastically reduced; in turn, application software, the finiteelement numerical simulation method, draw some different start-up pressure gradient ofpressure transmission diagram, different start-up pressure gradient with the curve of oilproduction, cumulative oil production; Seepage process, the well spacing and the size of theoil well output is proportional to the decrease of the amplitude, the crude oil of limit shearstress value is proportional to the extent of the oil well production. Permeability andproduction pressure difference and flow rate is inversely proportional to the degree ofreduced.