抽油井中气液混合物的压力梯度

本文探讨了抽油井环形空间中气液混合物的压力梯度。通过抽油井的室内模拟实验,研究了压力梯度校正系数的计算方法,得出了气液混合物的压力梯度校正系数与气体表观速度之间的关系以及空隙率与气体表观速度之间的关系。     

Numerical simulation of thermal convection of viscoelastic fluids in an open-top porous medium with constant heat flux

This paper makes a numerical study of the buoyancy-driven convection of a viscoelastic fluid saturated in an open-top porous square box under the constant heat flux boundary condition. The effects of the relaxation and retardation times on the onset of the oscillatory convection, the convection heat transfer rate and the flow pattern transition are investigated. It is shown that a large relaxation time can destabilize the fluid flow leading to an early onset of the thermal convection and a high heat transfer rate, while a large retardation time tends to stabilize the flow and suppress the convection onset and the heat transfer. After the convection sets in, the flow bifurcation appears earlier with the increase of the relaxation time and the decrease of the retardation time, resulting in more complicated flow patterns in the porous medium. Furthermore, with the increase of the ratio of the relaxation time to the retardation time, the fluid may be blocked from flowing through the open-top boundary, which may be caused by the viscoelastic effect. Finally, the comparison of our results with those under isothermal heating boundary conditions reveals that the heat transfer rate corresponding to a constant heat flux boundary is always higher.     

两种油管材料在模拟油田水溶液中的CO2腐蚀行为

    结合某油田现场应用情况,利用高压釜、扫描电镜和X-射线衍射(XRD)等手段,对比研究了N80和GB-N80-3Cr两种材料在模拟油田水环境中腐蚀行为.结果表明,温度对腐蚀速率影响较大,随着温度的增加,腐蚀速率呈增大趋势;温度高于60℃时,N80材料开始出现台地状局部腐蚀,而GB-N80-3Cr在所有测试温度下均未见局部腐蚀出现,且GB-N80-3Cr的腐蚀速率明显低于N80材料.