Abstract:Theoretical analyses and experimental results show that if the surface wettability of the porous media transfer from liquid-wetting to prior gas-wetting,the yield of the gas well can dramaticlly increase, and the degree of the gas-wetness also strongly affects the gas deliverability. However, for the reason that the gas has a strong ability of compressibility, the traditional liquid-wetting quantitative evaluation methods((USBM method 和Amott method))does not apply to gas-wetting evaluation. This paper concludes and establishes a new gas-wetting evaluation method on the basis of theoretical analyses and the experimental researches on the wettability: the sessile drop, the captive bubble, the surface energy, and the capillary tube rise. The Research Group first proposed the gas-wetting quantitative evaluation methods which are established on methods of the sessile drop and the captive bubble, confirmed the gas-wetting quantitative evaluation index, laying a solid foundation for the gas-wetting theoretical research.