Optimisation of Reservoir Flooding Using a Fast Simulator: The Capacitance Resistance Method
CHAU, Hao Tuan, LAM, Thanh Thai, VU, Luan Vuong Kinh
Engineering Honours, 2015
Australian School of Petroleum
University of Adelaide
Capacitance resistance model (CRM) has been known as a new concept and a fast simulator to predict the reservoir performance. Two mainly important advantages of CRM are requiring less input data and using analytical solutions that advantageously reduce time consuming and complexity of calculations. Additionally, CRM is an applicable method for predicting production rate, quantifying the well connectivity between injectors and producers and optimizing injection schemes to improve ultimate recovery.
Currently, single-phase CRM has some limitations. It neglects the water/oil saturation changes; excluding the pressure equation. This makes single-phase CRM only valid in mature waterflood. Therefore, two-phase CRM has been implemented and developed recently to solve the problem. Basically, two-phase CRM (coupled CRM) resolves both pressure and saturation equations, which helps to validate model parameters such as connectivity, time constant and saturation. In addition, the two-phase CRM is able to apply in both mature and immature waterflood. It improves the accuracy and reliability in oil rate prediction.
The methodology of our report is to develop analytical solutions of both single and coupled CRM. After history matching with production and injection data from ECLIPSE, a new model was built up based on coupled CRM to validate the application of both models. When the validation of both models was confirmed, the prediction and optimization stages were processed and integrated with fractional flow model to predict the ultimate oil recovery. Finally, sensitivity analysis was carried out to test the effects of reservoir properties of new coupled CRM.
This report concludes that the coupled CRM had a better result in predicting oil production rate in both immature and immature waterflood. It also demonstrates that fractional flow model obtained from coupled CRM is accurate to predict oil production rate in both immature and mature waterflood. Coupled CRM was capable to optimize injection scheme and yield the ultimate oil recovery.