中文摘要：

在凝析气藏的衰竭式开发过程中，当井底压力降至露点压力后，地层中流体发生反凝析现象，部分凝析油会滞留于地层中，导致采出物的组分变轻，生产气油比增大。但在雅克拉凝析气藏的开发中，当井底压力下降至露点压力以下时，大部分气井的生产气油比并没有上升，甚至部分气井的生产气油比大幅度下降。针对这一异常现象，通过动态分析、室内实验和数值模拟方法对其进行了研究，认为造成该区块气井生产气油比异常的主要原因包括水侵、射孔位置和近井地带的毛管数效应。通过对凝析气藏气油比的预测，认为气油比下降只是暂时的，随着压力的继续降低，凝析气井的生产气油比会迅速增大。

英文摘要：

During the depletion of condensate gas reservoir, retrograde condensation of formation fluid occurs when the bottom hole pressure drops to dew point pressure. Condensate oil would partly remain in formation, which would result in lighter component of produced material and increased production GOR. However, in the development of Yakela condensate gas reservoir, when the bottom hole pressure drops to dew point pressure, production GOR of most wells didnt increase, some even decreased greatly. This abnormal phenomenon is studied through dynamic a- nalysis, laboratory experiment and numerical simulation, and the result shows that the main reasons of abnormal GOR of the area includes water invasion, perforation location and near well capillary number effect. The prediction of condensate gas reservoir GOR shows that the decrease of GOR is temporary and along with the continuous decrease of pressure, the production GOR of condensate gas well would increase rapidly.