Performance comparison of Newton and Newton-GMRES methods in 3-D flow analysis

Yıldızlar, Buket
Because of CPU time problems, an alternative to Newton’s method is investigated in order to make a flow analysis in a 3-D Supersonic Nozzle. Calculation and forming of the Jacobian matrix get harder as the system gets larger. On the contrary, Newton-GMRES approach does not require direct access to the Jacobian matrix. Due to the fact that it provides a dramatic decrease in CPU time, Newton-GMRES method is examined. To compare their performance on a supersonic nozzle, 3-D Euler Equations are solved with Newton’s and Newton-GMRES methods respectively. A parametric study is conducted for Newton-GMRES method to find the optimal solution with respect to CPU times elapsed. In order to analyse Newton-GMRES method’s behavior on larger systems, different test cases are generated. The code is developed for Newton-GMRES method with Fortran77.


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Citation Formats
B. Yıldızlar, “Performance comparison of Newton and Newton-GMRES methods in 3-D flow analysis,” M.S. - Master of Science, Middle East Technical University, 2014.