Eventos Anais de eventos
ENCIT 2016
16th Brazilian Congress of Thermal Sciences and Engineering
EVALUATION OF THE DUAL-TIME STEP TECHNIQUE COUPLED WITH MINIMAL GAIN MARCHING SCHEME
Submission Author:
Renan de Souza Teixeira , RJ
Co-Authors:
Leonardo Santos de Brito Alves
Presenter: Renan de Souza Teixeira
doi://10.26678/ABCM.ENCIT2016.CIT2016-0475
Abstract
Reference solutions are quite important in many engineering applications. Stability analysis, initial conditions for unsteady problems and reference states for numerical sponge zones are some examples. Recently, the minimal gain marching scheme was developed to generate reference solutions for any type of unstable problem. This method consists to modify the original numerical scheme coefficients such a way that absolute numerical gain is smaller than one for the required frequency spectra. This approach allows the respective disturbance group amplitude decay given enough time. However, these ideas were applied and obtained for implicit schemes. An alternative is the dual-time step technique. This method modifies the original transient evolution of the governing equations. It creates a pseudo-time which any numerical scheme can be used without affecting the physical-time. This is done by introducing in the governing equations another physical-time derivative that minimal gain scheme can be used while the original scheme becomes a pseudo-time derivative. A physical-time accurate solution is then generated upon convergence towards pseudo-time steady-state in each physical-time step. The present paper will discuss the efficient implementation of the dual-time step coupled with minimal gain marching scheme. Different problems will be investigated to evaluate the convergence process of the coupled method and compared with damping methods available in the literature.
Keywords
Dual-time step technique, Steady-state flows, Numerical analysis, Damping Schemes, Dual-time step technique, Steady-state flows, Numerical analysis, Damping Schemes, Dual-time step technique, Steady-state flows, Numerical analysis, Damping Schemes
