Models comparison of CO2/water system in predicting dynamic and interfacial properties
(0) The geological CO2 storage in deep saline aquifers technology has been widely concerned as the most potential way to reduce emissions.For geological CO2 storage in deep saline aquifers,the migration of the stored supercritical CO2 and the interfacial properties between fluids in reservoir are important factors affecting the storage efficiency and capacity.Molecular dynamic simulation has been widely used to study the dynamic and interfacial properties of CO2/water system.The molecular structure and force field parameters are important to the accuracy of simulations,although there are many potential energy models for CO2/water,single model often has high accuracy only for a specific characteristic.It is necessary to find or develop a combined potential energy model that can describe the dynamic and interfacial properties with high accuracy simultaneously.In this study,a comprehensive comparison of the quality of different CO2/water force fields in predicting dynamic and interfacial properties is conducted.The models here we selected include seven different CO2 models(three rigid models and four flexible models)and three flexible water models.As a result,it was found that rigid CO2 model performs better than its flexible version in density,but has little difference in self-diffusion.The flexible model Zhu can give more accurate simulation results in density because of its smaller bond constants.The rigid model TraPPE is the best predictor of the self-diffusion coefficient,followed are TraPPE-flex and Zhu models.The accuracy of interfacial properties depends more on which water model was adopted,and it shows the F3C water model is the best choice within water models selected.Based on all simulation results,the Zhu-F3C model can accurately predict the dynamic and interfacial properties of the CO2/water system simultaneously.
molecular dynamic simulation geological CO2 storage self-diffusion interfacial tension
Wenfeng HU Cong CHEN Weizhong LI
Key Laboratory of Ocean Energy Utilization and Energy Conservation of Ministry of Education,Dalian University of Technology,Dalian 116024,P.R.China;School of Energy and Power Engineering,Dalian University of Technology,Dalian 116024,P.R.China
国际会议
武汉
英文
180-189
2018-08-21（万方平台首次上网日期，不代表论文的发表时间）