This paper studies the relations between the direction of waterflooding and the displacement efficiency in fractured reservoir dominated by capillary pressure, capillary pressure and driving pressure, and driving pressure respectively ,by using COMPIV simulation software developed by American SSI company.
18 dogs with hemorrhagic shock were divided into 3 groups. Group Ⅰwascontrol, group Ⅱ and Ⅲ were jetted with air or oxygen respectively and continuouslyoutside the glottis by HFJV (frequency 80 beat/min, driving pressure 0.2 MPa, I:E timeratio=1:2) during the uncompensated period.
The results showed that with the same f, driving pressure and I / E ratio, Paco2, VT and FRC were significantly lower while Vco2 and pH significantly higher in HFTJV than in high frequency jet ventilation (HFJV).
When driving pressure is lower, emergence time of CH radical is greater than the emergence time of C2 radical. As driving pressure is greater than 2. 7MPa, the e-mergence time of CH radical is close to the emergence time of C2 radical.
In oil field development, this reflects mainly: lowenergy utilization ratio, rapid productivity drop, poor water-intake capacity, high hit pressure around the water input well, slow becoming effectively of producing well and a great part of driving pressure is used to overcome the pressure gradient.
The effects of many factors on waterflooding in Ansai extra low permeability oil field, such as the stronger heterogeneity of reservoirs, the bigger starting pressure difference and driving pressure gradient, the natural fracture development and the declining productivity index after water breakthrough are getting increasingly strong.
Study shows that such a relationship between injector and producer is not established until the driving pressure gradient completely overcomes the starting pressure gradient of reservoirs. Hence, the injection-production well spacing corresponding to the minimum driving pressure gradient in overcoming the maximum starting pressure gradient should be a proper maximum injection-production well spacing that the pay zone can be effectively produced.
The model indicates that the regional principal stress difference was less than 0.05 times the driving pressure in the West Peak intrusion.
Then the equation of motion are established for an arbitrary time-dependent driving pressure.
In side-nozzle injection, penetration is found to increase with jet force number,N, given by the product of the gas driving pressure and the nozzle diameter.
Among the effects evaluated were those due to lance design, nozzle dimensions, gas driving pressure, and liquid density.
The thermodynamic driving pressure is calculated assuming paraequilibrium conditions, and the solute drag theory of Purdy and Brechet has been modified to remove the artifact of residual solute drag at zero interface velocity.