蒸汽吞吐过程中注汽时间对油/地层热影响半径的影响

针对蒸汽吞吐过程中因注汽时间不当而造成蒸汽资源浪费或油层加热不充分的问题,建立了井筒-地层-油层的二维、非稳态的油层的数学模型,分析了油层以及地层的温度场变化情况,在此基础之上探讨了注汽时间对油/地层热影响半径的影响。研究结果表明,油层热影响半径随着注汽时间的增加而增大,且在注汽至第5d时达到最大值,此后热影响半径基本维持不变;从注汽第3d开始,油层中的热量明显向地层传递,注汽6d后,油层与地层的温度分布基本相同;蒸汽吞吐过程中的注汽时间宜控制在4～5d。

Influence of Steam Injection Period to the Heat Affected Radius during the Steam Soak

The wasting of the superheated steam or heating the oil reservoir not sufficiently might be caused by the uncertainty of steam injection period during the steam soak, therefore, and a two--dimensional, unsteady state mineshaft-- stratum-- oil reservoir mathematical model was established, and the temperature fields of the stratum and the oil reservoir were analyzed. Furthermore, the influences of steam injection period to the heat affected radius during the steam soak were discussed. The results show that the heat affected radius of the oil reservoir increases with steam injection period duration and reaches the maximum when the steaming for 5 d, then nearly no longer changed after that. The heat in the oil reservoir began to transfer to the stratum when the steaming for 3 d, and the temperature fields of the stratum and the oil reservoir are nearly the same for 6 d. The steam injection period should be controlled in 4-5 d during the steam soak.