底水气藏气井水锥动态模拟及见水时间预测

国内外底水气藏开发实践中,底水锥进展核心问题,准确的见水时间预测,对于底水气藏开发具有重大意义。为解决底水气藏开发实践中存在的水锥动态难模拟、见水时间难预测等问题,基于底水气藏开发实践中射孔方案形成的3种渗流型态,建立了底水气藏气井渗流模型并推导了底水气藏气井的水锥动态模型及见水时间预测公式,综合考虑了气体非达西效应、表皮系数、原始束缚水饱和度、原始含气饱和度等因素对于见水时间的影响。实例研究结果表明,利用推导的公式进行气井水锥动态模拟及见水时间预测的结果符合气井的实际生产状况。研究成果对水驱气藏气井的配产具有现实意义,可有效指导底水气藏气井的科学开发。

Modeling of the water coning dynamics and the prediction of the water breakthrough time for the gas well in bottom-water gas reservoirs

In the development practice of the bottom-water gas reservoir at home and abroad, the bottom-water coring is the key problem, so the accurate prediction of the water breakthrough time possess the great significance for the reservoir development. For solving the problems of the difficulties in the coning dynamics and breakthrough time prediction and so on in the reservoir development, based on three kinds of the flow types and states formed in the perforation programs of the bottom-water gas reservoir, the flow model was established for the gas well in the reservoir and moreover the water-coning dynamic model and the predicting formula of the water breakthrough time for gas wells in the bottom-water gas reservoirs were deduced, the influences of the non-Darcy effect, skin coefficient/factor, initial irreducible water saturation, initial gas saturation and so forth on the water breakthrough time were comprehensively taken into account. The study results of the actual case show that with the help of the deduced formula, the coning dynamic model of the gas well and the predicted results of the water breakthrough time are accordant with the actual production conditions of the gas well. The research results possess a certain practical significance for the production allocation of the gas wells in the water-driven gas reservoirs, and moreover can effectively guide the scientific development of the gas well in the bottom-water gas reservoirs.