%-------------------------------------------------------------------------------
% UF Sparse Matrix Collection, Tim Davis
% http://www.cise.ufl.edu/research/sparse/matrices/Janna/Fault_639
% name: Janna/Fault_639
% [contact mechanics for model of a faulted gas reservoir]
% id: 2543
% date: 2011
% author: C. Janna, M. Ferronato
% ed: T. Davis
% fields: name title A id date author ed kind Zeros notes
% kind: structural problem
%-------------------------------------------------------------------------------
% notes:
% Authors: Carlo Janna and Massimiliano Ferronato                 
%                                                                 
% Symmetric Positive Definite Matrix                              
% # equations:  638802                                            
% # non-zeroes: 28614564                                          
% Problem description: contact mechanics                          
%                                                                 
% The matrix Fault_639 is obtained from a structural problem      
% discretizing a faulted gas reservoir with tetrahedral Finite    
% Elements and triangular Interface Elements.  The Interface      
% Elements are used with a Penalty formulation to simulate the    
% faults behaviour.  The problem arises from a 3D discretization  
% with three displacement unknowns associated to each node of the 
% grid.  Some further information may be found in the following   
% papers:                                                         
%                                                                 
% 1) M. Ferronato, G. Gambolati, C. Janna, P. Teatini. "Numerical 
% modelling of regional faults in land subsidence prediction above
% gas/oil reservoirs", International Journal for Numerical and    
% Analytical Methods in Geomechanics, 32, pp. 633-657, 2008.      
%                                                                 
% 2) M. Ferronato, C. Janna, G. Gambolati. "Mixed constraint      
% preconditioning in computational contact mechanics", Computer   
% Methods in Applied Mechanics and Engineering, 197, pp.          
% 3922-3931, 2008.                                                
%                                                                 
% 3) C. Janna, M. Ferronato, G. Gambolati. "Multilevel incomplete 
% factorizations for the iterative solution of non-linear FE      
% problems". International Journal for Numerical Methods in       
% Engineering, 80, pp. 651-670, 2009.                             
%                                                                 
% 4) C. Janna, M. Ferronato, G. Gambolati. "A Block FSAI-ILU      
% parallel preconditioner for symmetric positive definite linear  
% systems". SIAM Journal on Scientific Computing, 32, pp.         
% 2468-2484, 2010.                                                
%-------------------------------------------------------------------------------
