An integrated co-dact and adaptive analytical jacobian (Aaj) method for efficient and robust modeling of complex combustion chemistry

An adaptive analytical Jacobian (AAJ) method has been developed by integrating the correlated dynamic adaptive chemistry and transport (CO-DACT) method with an analytical Jacobian method for efficient and stable chemical integrations. The CO-DACT method can produce locally reduced chemiscal kinetics on-the-fly with negligible computational cost even for a large chemical kinetic model. Based on the locally reduced chemical kinetics, the analytical Jacobian method with sparse matrix solver is applied to integrate the ordinary differential equation (ODE) system with a reduced Jacobian matrix. The performances of the proposed AAJ method are compared with a benchmarked hybrid multi-timescale (HMTS) method. The results show that the AAJ method is accurate and stable. It and can accelerate the overall computation with much larger integration time steps.