Problem 1-Steady-state two-phase flow upward
Last updated
Last updated
This problem is from the first example in the user manual of T2Well/ECO2N Version 1.0. It was designed for verifying the wellbore flow solution approach through modeling the steady-state, isothermal, two-phase (CO2 as gas and water as liquid) flow in a vertical wellbore of 1000 m length.
The details of the problem are described below:
Table 10-2 Parameters of the example problem
Length
1000 m
Vertical wellbore
Diameter
0.1 m
Circular
Total mass flux
Gas+Liquid
Gas mass fraction
0.5
Temperature
40.0 ˚C
Isothermal
Wellhead pressure
100000 Pa
The specifications of the one-dimensional model are:
1000 m wellbore with a diameter of 0.1 m.
Grid resolution 10 m.
Injection mass rate at bottom: CO2: 0.19625 kg/s; water: 0.19625 kg/s (Each = 25 with a cross sectional area of 7.8500E-03 ).
Isothermal simulation with a uniform temperature of 40 °C throughout the wellbore.
Top boundary (outlet) pressure is 10000.0 Pa.
Wall roughness m.
Use ECO2 module for the simulation.
The input file for TOUGH4 simulation is modified from the input of T2well. Figure 10-n shows the main changes in the file, including two new data sections ( and ). The option IE(52)=-1 forces using change of the primary variables as convergence criteria for Newton iteration , which is very helpful in improving model convergence behavior. T2Well reached steady-state requires 4100 steps for this example, but T4Well needs only 174 steps to obtain the same results. IE(67)=1 is for selecting the same function as in T2Well/ECO2N Version 1.0 for the calculation of the acceleration loss.
The results from TOUGH4 numerical solution are almost identical to the analytical solutions (Pan et al., 2010) and the results from T2Well. Figure 10-m shows the comparison of simulated pressure, drift velocity, gas velocity and gas saturation along the wellbore at steady-sate by T2well and T4.well.
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Input Files:
Output Files:
