Finally, the parametric study investigates how the initial quantity of oil in the domain can influence the results.

Two simulations are carried out: one with the size of the inlet is reduced by two as it is shown in the pictures below:

* 37% of oil initialy in the domain 18% of oil initialy in the domain*

Simulation parameters are listed in the table below:

Velocity Inlet | Percentage of gaz injection | Percentage of oil recovered | |

37% oil initial | 0.6 m/s | 75% | 78% |

18% oil initial | 0.6 m/s | 75% | 66.5% |

After an injection of 75% of nitrogen, the percentage of oil recovered in function of the initial quantity of oil is higher when the initial quantity of oil is important.

These results were expected as every recovery method have difficulties to recover oil when the initial quantity is really small.

**Therefore, the initial amount of oil in the domain impact the efficiency of the recovery method. The oil recovery ratio will not be the same for every cave and will depends on the initial amound of oil present in the cave.**