Abstract: For the problem that gas well conventional systematic analysis doesn′t consider gas reservoir flow characteristic during prediction inflow performance by binomial method and so on, the coupling mechanism of the unsteady flow of fluid through porous medium and wellbore flowing is presented to perform productivity analysis, fully considering flow characteristic of gas reservoir, drainage area and formation pressure descending in the process of producing. By conventional production behavioral information, establishing controlled reserve of gas well, formation parameter, prediction the change of gaswell productivity and pressure under the circumstance of different exploration type and time, evaluating of recoverable reserves and effect of offset pressure, thereby, gas well working system is optimized.

Key words: dynamic analysis, nonsteady, coupling, productivity prediction, low permeability gas reservoir