mwang@watmath.UUCP (mwang) (05/08/84)
_U_N_I_V_E_R_S_I_T_Y _O_F _W_A_T_E_R_L_O_O _D_e_p_a_r_t_m_e_n_t _o_f _C_o_m_p_u_t_e_r _S_c_i_e_n_c_e _j_o_i_n_t_l_y _w_i_t_h _D_e_p_a_r_t_m_e_n_t _o_f _E_l_e_c_t_r_i_c_a_l _E_n_g_i_n_e_e_r_i_n_g Presents a Numerical Analysis Seminar on Multirate Integration Methods, Theory and Implementation with Dr. Stig Skelboe Institute of Datalog, University of Copenhagen, Copenhagen N, Denmark DATE: Monday, May 14 and Tuesday, May 15, 1984 at 3:30 PM ROOM: MC 6091A ABSTRACT In the simulation of many physical systems, the solu- tion components can be separated in two or more groups with widely varying rate of change. Classical discret- ization methods use the same mesh for the discretiza- tion of all parts of a system while multirate methods adapt the mesh for each sub-system to the rate of change of the variables describing that particular sub-system. This paper presents multirate integration formulas for stiff systems of ordinary differential equations. The multirate formulas are based on backward differentia- tion formulas, and the principles of an experimental implementation are discussed. The absolute stability properties are analyzed using a 2x2 linear test equa- tion system, and finally an example is given demon- strating the performance of the experimental implemen- tation. For further information please contact Prof. P. Bryant at ext. 3370. May 8, 1984