kelvin.c

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/*
%M This modules contains the KELVIN material sub-class methods and 
   definitions
%a Joao Luiz Elias Campos.
%d September 2nd, 1998.
%r $Id: kelvin.c,v 1.1 2004/06/22 05:29:59 joaoluiz Exp $
%w (C) COPYRIGHT 1995-1996, Eduardo Nobre Lages.
   (C) COPYRIGHT 1997-1999, Joao Luiz Elias Campos.
   All Rights Reserved
   Duplication of this program or any part thereof without the express
   written consent of the author is prohibited.

   Modificacao: 28/04/2005    Alexandre A. Del Savio
     Foram substituídas todas as alocações dinâmicas feitas com malloc 
     por calloc.

*/

/*
** ------------------------------------------------------------------------
** Global variables and symbols:
*/
#include <stdio.h>
#include <stdlib.h>

#include "load.h"
#include "elm.h"
#include "material.h"
#include "node.h"
#include "rio.h"


/* Parent method
 */
void MaterialDensity( sMaterial *, double * );


/*
** ------------------------------------------------------------------------
** Local variables and symbols:
*/

/*
%T KELVIN material data definition
*/
typedef struct _isodata
{
 double E;             /* Young modulos       */
 double Nu;            /* Poisson coefficient */
 double N;             /* Viscosity parameter */
} sKelvinData;


/*
** ------------------------------------------------------------------------
** Local functions:
*/


/*
** ------------------------------------------------------------------------
** Subclass methods:
*/
static void KelvinNew        ( int, sMaterial ** );
static void KelvinFree       ( sMaterial * );
static void KelvinRead       ( sMaterial * );
static void KelvinEParameter ( sMaterial *, double * );
static void KelvinNuParameter( sMaterial *, double * );
static void KelvinCMatrix    ( sMaterial *, double [6][6] );
static void KelvinTimeStep   ( sMaterial *, double * );


/*
%F This method allocates memory for a KELVIN material and fills its 
   data with the specific values.
%i Material label (number)
%o Material descriptor.
*/
static void KelvinNew( int label, sMaterial **mat )
{
 sKelvinData *data = 0L;

/* Get memory for the material descriptor
 */
 (*mat) = (sMaterial *)calloc(1, sizeof(sMaterial));

/* Get memory for the KELVIN material data
 */
 data = (sKelvinData *)calloc(1, sizeof(sKelvinData));

/* Fill KELVIN material data
 */
 data->E  = 0.0;
 data->Nu = 0.0;
 data->N  = 0.0;

/* Fill material descriptor
 */
 (*mat)->type  = KELVIN;
 (*mat)->label = label;
 (*mat)->Gamma = 0.0;
 (*mat)->data  = (void *)data;

/* Add to the material list
 */
 MatList[label-1] = (*mat);

} /* End of KelvinNew */


/*
%F This method frees the KELVIN material data for a given material.
%i Material descriptor.
*/
static void KelvinFree( sMaterial *mat )
{
 sKelvinData *data = 0L;

/* Get KELVIN material data
 */
 data = (sKelvinData *)mat->data;

/* Release allocated memory
 */
 free( data );

/* Reset material data
 */
 mat->data = 0L;

} /* End of KelvinFree */


/*
%F This method reads the KELVIN material information.
%i Material descriptor.
*/
static void KelvinRead( sMaterial *mat )
{
 sKelvinData *data = 0L;
 double       e, nu, n;

/* Get the material data
 */
 data = (sKelvinData *)mat->data;

/* Read the material parameters
 */
 fscanf( nf, "%lf %lf %lf", &e, &nu, &n );

/* Fill material information
 */
 data->E  = e;
 data->Nu = nu;
 data->N  = n;

} /* End of KelvinRead */


/*
%F
*/
static void KelvinEParameter( sMaterial *mat, double *e )
{
 sKelvinData *data = 0L;

/* Get material descriptor
 */ 
 data = (sKelvinData *)mat->data;

/* Get Young modules parameters
 */
 (*e) = data->E;

} /* End of KelvinEParameter */


/*
%F
*/
static void KelvinNuParameter( sMaterial *mat, double *nu )
{
 sKelvinData *data = 0L;

/* Get material descriptor
 */ 
 data = (sKelvinData *)mat->data;

/* Get Poisson coefficient parameters
 */
 (*nu) = data->Nu;

} /* End of KelvinNuParameter */


/*
%F This function computes the material constitutive matrix
*/
static void KelvinCMatrix( sMaterial *mat, double cm[6][6] )
{
 int          i, j;
 sKelvinData *data = 0L;
 double       e, nu;

/* Intialize matrix
 */
 for( i = 0; i < 6; i++ )
  for( j = 0; j < 6; j++ )
   cm[i][j] = 0.0;

/* Get material descriptor
 */
 data = (sKelvinData *)mat->data;

/* Get element parameters
 */
 e  = data->E;
 nu = data->Nu;

/* Compute matrix elements
 */
 if( NDof == 3 )
 {
  cm[0][0] =
  cm[1][1] =
  cm[2][2] =  e*(nu*nu-1.0) / (nu*(nu+nu*nu)+nu*(nu*nu+nu)+nu*nu-1.0);
  cm[1][0] =
  cm[2][0] =
  cm[0][1] =
  cm[2][1] =
  cm[0][2] =
  cm[1][2] = -e*(nu*nu+nu) / (nu*(nu+nu*nu)+nu*(nu*nu+nu)+nu*nu-1.0);
  cm[3][3] =
  cm[4][4] =
  cm[5][5] = (e * e) / (e + e * (1.0 + 2.0 * nu));
 }
 else
 {
  cm[0][0] = cm[1][1] = (e * (1.0 - nu)) / ((1.0 + nu) * (1.0 - (2.0 * nu)));
  cm[0][1] = cm[1][0] = (e * nu) / ((1.0 + nu) * (1.0 - (2.0 * nu)));
  cm[2][2] = e / (2.0 * (1.0 + nu));
 }
 
} /* End of KelvinCMatrix */


/*
%F
*/
static void KelvinTimeStep( sMaterial *mat, double *dt )
{
 sKelvinData *data = 0L;
 double       e, nu, n;

/* Get material data
 */
 data = (sKelvinData *)mat->data;

/* Get material parameters
 */
 e  = data->E;
 nu = data->Nu;
 n  = data->N;

/* Compute time step
 */
 (*dt) = 2.0 * n * ((1.0 + nu) / e);

} /* End of KelvinTimeStep */


/*
** ------------------------------------------------------------------------
** Public functions:
*/

/*
%F This function initializes the sub-class "KELVIN".
*/
void KelvinInit( void );
void KelvinInit( void )
{
/* Initialize KELVIN material sub-class
 */
 MatClass[KELVIN].new       = KelvinNew;
 MatClass[KELVIN].free      = KelvinFree;
 MatClass[KELVIN].read      = KelvinRead;
 MatClass[KELVIN].epar      = KelvinEParameter;
 MatClass[KELVIN].nupar     = KelvinNuParameter;
 MatClass[KELVIN].cmatrix   = KelvinCMatrix;
 MatClass[KELVIN].updatestr = 0L;
 MatClass[KELVIN].updatepar = 0L;
 MatClass[KELVIN].timestep  = KelvinTimeStep;
 MatClass[KELVIN].density   = MaterialDensity;
 MatClass[KELVIN].vstrain   = 0L;
 
 
} /* End of KelvinInit */


/* =======================================================  End of File  */

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