## 3 Results and Discussion
### Analysis of Influence Factors on CO\({}_{2}\)-Wag  
To analyze the principal influence factors of CO\({}_{2}\)-WAG, this work designs a series of scenarios of the CO\({}_{2}\)-WAG development method by modifying the CO\({}_{2}\)-WAG period, fluid injection rate, and water-gas ratio based on the above base model. Among them, six schemes of the period adjustment are set as 4 months, 6 months, 12 months, 24 months, 48 months, and 96 months, respectively. Six schemes of the fluid injection rate adjustment are set as: (1) water injection rate of 65 m\({}^{3}\)/day and CO\({}_{2}\) injection rate of 12,000 m\({}^{3}\)/day; (2) water injection rate of 79 m\({}^{3}\)/day and CO\({}_{2}\) injection rate of 16,000 m\({}^{3}\)/day; (3) water injection rate of 90 m\({}^{3}\)/day and CO\({}_{2}\) injection rate of 20,000 m\({}^{3}\)/day; (4) water injection rate of 100 m\({}^{3}\)/day and CO\({}_{2}\) injection rate of 23,000 m\({}^{3}\)/day; (5) water injection rate of 110 m\({}^{3}\)/day and CO\({}_{2}\) injection rate of 27,000 m\({}^{3}\)/day; (6) water injection rate 120 m\({}^{3}\)/day and CO\({}_{2}\) injection rate of 31,000 m\({}^{3}\)/day. 6 schemes of the water-gas ratio adjustment are set as 0.33, 0.5, 1, 1.5, 2, and 3, respectively. Therefore, this work constructs a total of 6 \(\times\) 6 \(\times\) 6 = 216 scenarios. As the water injection rate varies simultaneously with the CO\({}_{2}\) injection rate, this work selects the CO\({}_{2}\) injection rate as one feature, and the period and water-gas ratio as the other two features. Figure 8: Gas oil ratio of the production in the WAG and CO\({}_{2}\) flooding. The cumulative oil production, CO\({}_{2}\) storage amount, and CO\({}_{2}\) storage efficiency of the 216 scenarios are simulated by CMG, and the results are detailed in Supporting Information. To elucidate more clearly the influence of CO\({}_{2}\)-WAG parameters on production, the cumulative oil production, CO\({}_{2}\) storage amount, and CO\({}_{2}\) storage efficiency of different cycle schemes (#85, #97, #103), different fluid injection rate schemes (#49, #121, #193), and different water-gas ratio schemes (#85, #87, #89) are compared by the single variable method, and the results are shown in Figures 9-11. As shown in Figure 9, the influence of the cycle on oil production is relatively small. When the CO\({}_{2}\)-WAG cycle is relatively shorter, the cumulative oil production is higher. When the cycle is 8 years, the cumulative oil production starts to decline significantly, because in this case, the frequency of alternating water and carbon dioxide is low, similar to a small period of water flooding and gas flooding. The influence of the cycle on CO\({}_{2}\) storage is relatively large, both in terms of CO\({}_{2}\) storage amount and CO\({}_{2}\) storage efficiency. Throughout the production process, CO\({}_{2}\) storage amount and CO\({}_{2}\) storage efficiency fluctuate due to the alternate injection of water and CO\({}_{2}\). At the end of the process, the CO\({}_{2}\) storage amount and CO\({}_{2}\) storage efficiency decrease with the cycle. As shown in Figure 10, the injection rate has a greater impact on oil production. As the injection rate increases, cumulative oil production also increases, but the CO\({}_{2}\) storage efficiency decreases. This is because more CO\({}_{2}\) will return to the surface from production wells as output gas when the CO\({}_{2}\) injection rate increases. Therefore, when optimizing the CO\({}_{2}\)-WAG extraction scheme in the oilfield, the injection rate cannot be increased arbitrarily. The processing capacity of gas treatment stations in the oilfield needs to be considered. When CO\({}_{2}\) output is too fast, some CO\({}_{2}\) will not be recovered and treated in time. CO\({}_{2}\) will escape into the atmosphere, which may cause environmental issues and aggravate the greenhouse effect. It also causes waste of CO\({}_{2}\) gas resources and economic loss to the oilfield.