Analytical model for influence of hydraulic pressure losses in horizontal gas wells on productivity

Aim. The purpose of the present work is to develop a method for estimation influence of hydraulic pressure losses in horizontal gas wells on productivity. Tasks to be solved are the development of an analytical model that describes the effect of hydraulic pressure losses along horizontal wellbore on the productivity distribution, determination of the main dimensionless factors describing process, solution for pressure distribution along a horizontal wellbore and generalization of solution in graphical and analytical correlations form.

Matherials and methods. The process in question is described by the analytical mathematical model consisting of differential equations in dimensionless form. Equations are solved numerically, solution is presented in graphical and analytical correlation form.

Results. Influence of hydraulic pressure losses in horizontal wellbore on productivity described by adjusting the coefficient “b” of nonlinear part of gas well inflow equation. Main factors influencing on “b” value is dimensionless length of horizontal wellbore, dimensionless nonlinearity factor of well inflow, exponent on Reynolds number in liner friction law. Value of coefficient “a” of linear part of gas well inflow equation does not depend on hydraulic pressure losses in a horizontal wellbore.

Conclusions. The results of the work can used for estimation the productivity of horizontal gas wells taking into account hydraulic pressure losses in a horizontal wellbore, for estimation influence of hydraulic pressure losses on productivity and to estimate the optimal length and diameter of a horizontal wellbore liner, as well as in simplified analytical integrated models of gas field development.

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