10.15131/shef.data.5364229.v1
Olivier Piller
Sylvan Elhay
Jochen Deuerlein
Angus Simpson
CCWI2017: F41 'Why are Line Search Methods Needed for Hydraulic DDM and PDM Solvers?'
2017
The University of Sheffield
CCWI2017
Steady state modelling
Convergence
Inexact line search method
2017-09-01 15:23:24
article
https://figshare.shef.ac.uk/articles/CCWI2017_F41_Why_are_Line_Search_Methods_Needed_for_Hydraulic_DDM_and_PDM_Solvers_/5364229
It is common that non-convergence problems occur for simulations under normal or abnormal operations. Among the main causes, there are the use of sublinear functions for calculation of the hydraulic steady-state, some derivative issues and an ill-conditioned iteration matrix in the solution method. The objective of this paper is to specify non-convergence cases for existing hydraulic software solutions. The damped Newton solution together with regularization techniques are proposed for ensuring global convergence, whatever the initial solution. Failures of convergence are shown to exist even on small case studies.