TAN Xianhong, LIANG Bin, WANG Shuai, et al. A productivity evaluation method of gas wells in condensate gas reservoirs with low permeability[J]. Petroleum Reservoir Evaluation and Development, 2021, (5): 724-729. DOI: 10.13809/j.cnki.cn32-1825/te.2021.05.009.
When the conventional binomial productivity equation is used to analyze the deliverability of the gas wells in a low permeability thick layer condensate gas reservoir with high condensate content in Bohai Sea
the negative deliverability equation coefficient B can be obtained
which is still negative after pressure correction. Therefore
this equation is not suitable for the gas well productivity analysis. In order to obtain the reasonable productivity equation of the gas well
the following measures are taken.Firstly
the judgment criterion of high-speed non Darcy seepage and the theoretical calculation of productivity equation coefficient B are used to confirm that the high-speed non Darcy of the gas well is negligible
and the formation pressure and bottom hole flow pressure also need to be corrected. Then
the modified productivity equation is obtained without high-speed non Darcy productivity equation. Finally
the exponential productivity equation is used for verification
and the calculated QAOF(open flow
the same below)is basically consistent with the QAOFthe modified productivity equation. When this new method is applied to the actual gas wells in low permeability condensate gas fields
a reasonable gas well productivity equation can be obtained
which shows the effectiveness of the modified productivity equation.