Problem 3 - Five-spot Geothermal Production/Injection (rfp)

This example is from EOS1 manual, sample 3 (rfp). The problem considers a large well field with wells arranged in a “five-spot” configuration (Figure 10-2). Because of symmetry only 1/8 of the basic pattern needs to be modeled. The grid has six rows, each containing between one and eleven elements, for a total of thirty-six volume elements; for simplicity, only a single layer of 305 m thickness is modeled. The problem specifications as given in Table 10-1 correspond to conditions that may typically be encountered in deeper zones of hot and fairly tight fractured two-phase reservoirs (Pruess and Narasimhan, 1985).

Figure 10-2 Five-spot well pattern with grid for modeling a 1/8 symmetry domain.

Table 10-1 Parameters for five-spot problem

Rock grain density	2650 $kg/m^{3}$
Specific heat	1000 J/kg˚C
Heat conductivity	2.1 W/m˚C
Permeable volume fraction	2%
Porosity in permeable domain	50%
Impermeable blocks: cubes with side length	50m, 250 m
Permeability	6.0x$10^{-15}m^{2}$
Thickness	305 m
Relative permeability: Corey curves
irreducible liquid saturation	0.30
irreducible gas saturation	0.05
Initial Conditions
Temperature	300 ˚C
Liquid saturation	0.99
Pressure	85.93 bar
Production/Injection
Pattern area	1 $km^{2}$
Distance between producers and injectors	707.1 m
Production rate (for full well)	30 kg/s
Injection rate (for full well)	30 kg/s
Injection enthalpy	500 kJ/kg

The simulations were run in effective porous medium and MINC conceptual model. Details can be found in EOS1 manual. This example was modified to demonstrate the simulation of transport of tracers. Two synthetic decay chain tracers tr1 and tr2 were included in the model. tr1 is injected together with the injection of water. It decays with a product of tr2. Additional input for definition of tracers through the keyword "TRACR" is needed for this simulation.

Followings are the simulation input files and output files:

Effective porous medium model: Input files output files

MINC model: Input files output files

Tracer model: Input files output Files