For modeling of gas production we use the system of equations obtained from the mass and energy conservation laws and the Darcy law which substitutes for a motion equation. The system is closed by physical and caloric equations of imperfect gas state. If gas extraction is sufficiently in-tensive, the energy transfer due to heat conduction can be considered negligibly small as compared to the convective transfer.

On the wall of a well we assume a constant pressure boundary condition and on the external boundary – the absence of flows of filtering gas and heat flow, i.e. the water drive of gas extraction is modeled. To solve the corresponding initial boundary-value problem we approximate the equation for gas pressure by the purely implicit absolutely stable difference scheme and the energy equation – by the unconditionally stable upwind scheme.

Calculations show that changes in the temperature field are essential only in case of the in-tensive gas-production. The role of temperature, despite as it might seem insignificantly influences pressure redistribution, affects prediction of the total gas production strongly enough. Underestima-tion of the role of temperature field changes makes 41% at the production with high intensity. At low intensity the amount of the recovered gas grows more intensively in the isothermal conditions. This implies that neglect of the temperature influence causes overestimation of the potential gas production.

The results obtained are of great applied significance as they show that at mathematical sim-ulation of natural gas production it is very important to take into account thermodynamic processes.

Abstracts file: | Abstract.doc |

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