Analysis Of Water Discharge Law And Production Dynamics Of Fractured Water Drive Gas Reservoirs

Naturally fractured gas reservoir and conventional gas reservoir have a significantly difference on pore-throat structure and percolation mechanism. Therefore, recognizing the complex relation between gas and water, gas reservoir with edge and bottom water energy size andidentifying early water invasion model of developing this kind of gas reservoir has important practical significance.Based on gas reservoir engineering, this article studies water influx calculation and water flooding gas reservoir reserve calculation and gives a computer program. In aspect of seepage mechanics and numerical simulation, we do a lot of research on the water drive gas reservoir dynamic development, water invasion modes and the main influence factors. At last, combined with X Gasfield project case is analyzed. The main work and achievements are as follows:(1) From theanglesofmacro-accounting, micro-accounting, this article analyses on the causes of confined gas.(2) By using VB compiled three kinds of calculating water influx method:Van Everdingen-Hurst method, Carter-Tracy method and Fetkovich method, and it analyses their applicable conditions to calculate water influx for different types of water bodies and water flow pattern. Based on the material balance of water drive gas reservoir dynamic reserves calculation method research, by using VBA, we come up with a set of from water drive gas reservoir water influx to dynamic reserves calculation to water flooding degree judgment system method.(3) Fractured double porosities water drive gas reservoir mechanism model is established using the Eclipse numerical simulation software; In the homogeneous model with the edge and bottom water, it quantitatively and qualitatively analyses the effects of the parameters for water law and dynamic production in the water drive gas reservoir.(4) Heterogeneous model is established to simulate water invasion models, study the influences by the factors like fracture direction, high permeability zone, inter-layer, fault, etc.(5) The X gas field project researches and analyses various water invasion modes and their effect on production performance, determines the water invasion route, water influx and calculates its water influx and dynamic reservesusing the program.Through the above researches, The paper formssome understanding and summaries on fractured water drive gas reservoir development, including water seal mechanism, water influx calculation, dynamic reserves calculation, various water invasion models simulation analysis and crack of water drive gas reservoir water law and the production of dynamic influence factors research, so that it provides certain theoretical basis on fractured water drive gas reservoir reasonable development.