The Numerical Simulation Study Of Gas Field Development

In these years, the energy consumption of our country is increasing sharply. But theincreasing of oil production is limited. So, as a high efficiency energy sources, the effect ofnatural gas will be more and more important. Though the gas resource is abundant, most ofthem are low permeability or ultra-low permeability sources. The most of them are typicaldeformable gas fields, and the percolation mechanism is different from the fluid flow intraditional gas fields. How to develop these kinds of fields are very important things thatmust to be solved, and the percolation mechanism is the key of gas field development. Thepercolation mechanism for deformable gas fields was studied deeply based on the lab resultsand theoretical investigation.On the base of the deformation of experiment, the characteristics of porosity andpermeability versus effective pressure were discovered. Combining percolation mechanism,reservoir engineering and numerical simulation, the corresponding mathematical model wasestablished. Utilizing finite difference method, a three-dimension and gas-water numericalmodel was derived, and the corresponding numerical simulator was developed.A conceptual model of gas reservoir was established to simulate. For the first, the resultof taking no account of deformable media was simulated, and in order to prove thereliability of this simulator, it was contrasted to the result of Eclipse software. For thesecond, with the same initial productivity, the curves of bottom hole flowing pressure,productivity and cumulative gas production were contrasted to analyze the effect of differentmedia on stable production time, recovery efficiency in stable production stage and so on.For the third, stable production time, recovery efficiency in stable production stage etc. werestudied with different productivities. For the last, Wuzhan gas field was studied by thissoftware. On the base of the history match, the performance prediction of Wuzhan gas fieldwas simulated. Then, a new spacing project was proposed, and the relation of single wellincome rate and dynamic investment recovery period vs. nature gas price were studied.The research findings of this thesis, not only has important academic signification, butalso provide tech support to the economic and effective development of gas fields,especially the low permeability gas reservoirs.