1 /*****************************************************************************
2  *
3  *  Elmer, A Finite Element Software for Multiphysical Problems
4  *
5  *  Copyright 1st April 1995 - , CSC - IT Center for Science Ltd., Finland
6  *
7  *  This program is free software; you can redistribute it and/or
8  *  modify it under the terms of the GNU General Public License
9  *  as published by the Free Software Foundation; either version 2
10  *  of the License, or (at your option) any later version.
11  *
12  *  This program is distributed in the hope that it will be useful,
13  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
14  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  *  GNU General Public License for more details.
16  *
17  *  You should have received a copy of the GNU General Public License
18  *  along with this program (in file fem/GPL-2); if not, write to the
19  *  Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
20  *  Boston, MA 02110-1301, USA.
21  *
22  *****************************************************************************/
23 
24 /*******************************************************************************
25  *
26  * Definitions for 8 node brick volume element.
27  *
28  *******************************************************************************
29  *
30  *                     Author:       Juha Ruokolainen
31  *
32  *                    Address: CSC - IT Center for Science Ltd.
33  *                                Keilaranta 14, P.O. BOX 405
34  *                                  02101 Espoo, Finland
35  *                                  Tel. +358 0 457 2723
36  *                                Telefax: +358 0 457 2302
37  *                              EMail: Juha.Ruokolainen@csc.fi
38  *
39  *                       Date: 27 Sep 1995
40  *
41  *                Modified by:
42  *
43  *       Date of modification:
44  *
45  ******************************************************************************/
46 
47 #include "../elmerpost.h"
48 #include <elements.h>
49 
50 /*
51  * Isoparametric 20 node volume element.
52  *
53  *                             7------18-------6
54  *                           19|             17|
55  *                           / |             / |
56  *                          4------16-------5  |
57  *                          | 15            |  14
58  *                          |  |            |  |
59  *                         12  |           13  |
60  *                          |  3-----10-----|--2
61  *                          | 11            | 9        w v
62  *                         w|/v             |/         |/
63  *                          0-------8-------1           ---u
64  *                           u
65  *
66  * shape functions:  N  = (1+u u)(1+v v)(1+w w)(u u+v v+w w-2)/8   i = 0..7
67  *                    i       i      i      i    i   i   i
68  *                   N  = (1-u^2)(1+v v)(1+w w)/4     i=8,10,16,18  (u = 0)
69  *                    i              i      i                         i
70  *                   N  = (1+u u)(1-v^2)(1+w w)/4     i=9,11,17,19  (v = 0)
71  *                    i       i             i                         i
72  *                   N  = (1+u u)(1+v v)(1-w^2)/4     i=12,13,14,15 (w = 0)
73  *                    i       i      i                                i
74  *
75  * @/@u              N  =  u (1+v v)(1+w w)(2u u+v v+w w-1)/8      i = 0..7
76  *                    i     i    i      i     i   i   i
77  * @/@u              N  = -2u(1+v v)(1+w w)/4         i=8,10,16,18  (u = 0)
78  *                    i          i      i                             i
79  * @/@u              N  =  u (1-v^2)(1+w w)/4         i=9,11,17,19  (v = 0)
80  *                    i     i           i                             i
81  * @/@u              N  =  u (1+v v)(1-w^2)/4         i=12,13,14,15 (w = 0)
82  *                    i     i    i                                    i
83  *
84  */
85 
86 static double A[20][20],N[20][20];
87 
88 static double NodeU[] = {
89      -1.0,  1.0,  1.0, -1.0, -1.0,  1.0, 1.0, -1.0, 0.0,  1.0,
90       0.0, -1.0, -1.0,  1.0,  1.0, -1.0, 0.0,  1.0, 0.0, -1.0
91    };
92 
93 static double NodeV[] = {
94      -1.0, -1.0,  1.0,  1.0, -1.0, -1.0,  1.0, 1.0, -1.0, 0.0,
95       1.0,  0.0, -1.0, -1.0,  1.0,  1.0, -1.0, 0.0,  1.0, 0.0
96    };
97 
98 static double NodeW[] = {
99      -1.0, -1.0, -1.0, -1.0, 1.0, 1.0, 1.0, 1.0, -1.0, -1.0,
100      -1.0, -1.0,  0.0,  0.0, 0.0, 0.0, 1.0, 1.0,  1.0,  1.0
101    };
102 
103 
104 /*******************************************************************************
105  *
106  *     Name:        elm_20node_brick_triangulate( geometry_t *,element_t * )
107  *
108  *     Purpose:     Triangulate an element. The process also builds up an edge
109  *                  table and adds new nodes to node table. The triangulation
110  *                  and edge table is stored in geometry_t *geom-structure.
111  *
112  *     Parameters:
113  *
114  *         Input:   (geometry_t *) pointer to structure holding triangulation
115  *                  (element_t  *) element to triangulate
116  *
117  *         Output:  (geometry_t *) structure is modified
118  *
119  *   Return value:  FALSE if malloc() fails, TRUE otherwise
120  *
121  ******************************************************************************/
elm_20node_brick_triangulate(geometry_t * geom,element_t * brick)122 static int elm_20node_brick_triangulate( geometry_t *geom,element_t *brick )
123 {
124     element_t quad;
125     int i,j;
126 
127     if ( GlobalOptions.VolumeSides )
128     {
129       int topo[4];
130 
131       quad.DisplayFlag = TRUE;
132       quad.Topology = topo;
133       for( i=0; i<MAX_GROUP_IDS; i++ ) quad.GroupIds[i] = brick->GroupIds[i];
134 
135       for( i=0; i<6; i++ )
136       {
137           for( j=0; j<4; j++ )
138           {
139             quad.Topology[j] = brick->Topology[ElmBrickFace[i][j]];
140           }
141           if ( !elm_4node_quad_triangulate( geom, &quad, brick ) ) return FALSE;
142       }
143     } else {
144       if ( !geo_add_edge( geom, brick->Topology[0],  brick->Topology[8],  brick ) ) return FALSE;
145       if ( !geo_add_edge( geom, brick->Topology[8],  brick->Topology[1],  brick ) ) return FALSE;
146       if ( !geo_add_edge( geom, brick->Topology[1],  brick->Topology[9],  brick ) ) return FALSE;
147       if ( !geo_add_edge( geom, brick->Topology[9],  brick->Topology[2],  brick ) ) return FALSE;
148       if ( !geo_add_edge( geom, brick->Topology[2],  brick->Topology[10], brick ) ) return FALSE;
149       if ( !geo_add_edge( geom, brick->Topology[10], brick->Topology[3],  brick ) ) return FALSE;
150       if ( !geo_add_edge( geom, brick->Topology[3],  brick->Topology[11], brick ) ) return FALSE;
151       if ( !geo_add_edge( geom, brick->Topology[11], brick->Topology[0],  brick ) ) return FALSE;
152       if ( !geo_add_edge( geom, brick->Topology[0],  brick->Topology[12], brick ) ) return FALSE;
153       if ( !geo_add_edge( geom, brick->Topology[12], brick->Topology[4],  brick ) ) return FALSE;
154       if ( !geo_add_edge( geom, brick->Topology[1],  brick->Topology[13], brick ) ) return FALSE;
155       if ( !geo_add_edge( geom, brick->Topology[13], brick->Topology[5],  brick ) ) return FALSE;
156       if ( !geo_add_edge( geom, brick->Topology[2],  brick->Topology[14], brick ) ) return FALSE;
157       if ( !geo_add_edge( geom, brick->Topology[14], brick->Topology[6],  brick ) ) return FALSE;
158       if ( !geo_add_edge( geom, brick->Topology[3],  brick->Topology[15], brick ) ) return FALSE;
159       if ( !geo_add_edge( geom, brick->Topology[15], brick->Topology[7],  brick ) ) return FALSE;
160       if ( !geo_add_edge( geom, brick->Topology[15], brick->Topology[7],  brick ) ) return FALSE;
161       if ( !geo_add_edge( geom, brick->Topology[4],  brick->Topology[16], brick ) ) return FALSE;
162       if ( !geo_add_edge( geom, brick->Topology[16], brick->Topology[5],  brick ) ) return FALSE;
163       if ( !geo_add_edge( geom, brick->Topology[5],  brick->Topology[17], brick ) ) return FALSE;
164       if ( !geo_add_edge( geom, brick->Topology[17], brick->Topology[6],  brick ) ) return FALSE;
165       if ( !geo_add_edge( geom, brick->Topology[6],  brick->Topology[18], brick ) ) return FALSE;
166       if ( !geo_add_edge( geom, brick->Topology[18], brick->Topology[7],  brick ) ) return FALSE;
167       if ( !geo_add_edge( geom, brick->Topology[7],  brick->Topology[19], brick ) ) return FALSE;
168       if ( !geo_add_edge( geom, brick->Topology[19], brick->Topology[4],  brick ) ) return FALSE;
169     }
170 
171     return TRUE;
172 }
173 
174 /*******************************************************************************
175  *
176  *     Name:        elm_20node_brick_shape_functions( )
177  *
178  *     Purpose:     Initialize element shape function array. Internal only.
179  *
180  *     Parameters:
181  *
182  *         Input:   Global (filewise) variables NodeU,NodeV,NodeW
183  *
184  *         Output:  Global (filewise) variable N[8][8], will contain
185  *                  shape function coefficients
186  *
187  *   Return value:  void
188  *
189  ******************************************************************************/
elm_20node_brick_shape_functions()190 static void elm_20node_brick_shape_functions()
191 {
192      double u,v,w;
193      int i,j;
194 
195      for( i=0; i<20; i++ )
196      {
197          u = NodeU[i];
198          v = NodeV[i];
199          w = NodeW[i];
200 
201          A[i][0]  = 1;
202          A[i][1]  = u;
203          A[i][2]  = v;
204          A[i][3]  = w;
205          A[i][4]  = u*v;
206          A[i][5]  = u*w;
207          A[i][6]  = v*w;
208          A[i][7]  = u*v*w;
209          A[i][8]  = u*u;
210          A[i][9]  = v*v;
211          A[i][10] = w*w;
212          A[i][11] = u*u*v;
213          A[i][12] = u*u*w;
214          A[i][13] = u*v*v;
215          A[i][14] = u*w*w;
216          A[i][15] = v*v*w;
217          A[i][16] = v*w*w;
218          A[i][17] = u*u*v*w;
219          A[i][18] = u*v*v*w;
220          A[i][19] = u*v*w*w;
221      }
222 
223      lu_mtrinv( (double *)A,20 );
224 
225      for( i=0; i<20; i++ )
226         for( j=0; j<20; j++ ) N[i][j] = A[j][i];
227 }
228 
229 /*******************************************************************************
230  *
231  *     Name:        elm_20node_brick_fvalue( double *,double,double,double )
232  *
233  *     Purpose:     return value of a quantity given on nodes at point (u,v,w)
234  *                  Use trough (element_type_t *) structure.
235  *
236  *     Parameters:
237  *
238  *         Input:  (double *) quantity values at nodes
239  *                 (double,double,double) point where values are evaluated
240  *
241  *         Output:  none
242  *
243  *   Return value:  quantity value
244  *
245  ******************************************************************************/
elm_20node_brick_fvalue(double * F,double u,double v,double w)246 static double elm_20node_brick_fvalue(double *F,double u,double v,double w)
247 {
248      double R=0.0,uv=u*v,uw=u*w,vw=v*w,uvw=u*v*w,uu=u*u,vv=v*v,ww=w*w,
249                   uuv=uu*v,uuw=uu*w,uvv=u*vv,uww=u*ww,vvw=vv*w,vww=v*ww,
250                   uuvw=uu*vw,uvvw=vv*uw,uvww=uv*ww;
251      int i;
252 
253      for( i=0; i<20; i++ )
254      {
255          R += F[i]*( N[i][0]       +
256                      N[i][1]*u     +
257                      N[i][2]*v     +
258                      N[i][3]*w     +
259                      N[i][4]*uv    +
260                      N[i][5]*uw    +
261                      N[i][6]*vw    +
262                      N[i][7]*uvw   +
263                      N[i][8]*uu    +
264                      N[i][9]*vv    +
265                      N[i][10]*ww   +
266                      N[i][11]*uuv  +
267                      N[i][12]*uuw  +
268                      N[i][13]*uvv  +
269                      N[i][14]*uww  +
270                      N[i][15]*vvw  +
271                      N[i][16]*vww  +
272                      N[i][17]*uuvw +
273                      N[i][18]*uvvw +
274                      N[i][19]*uvww );
275      }
276 
277      return R;
278 }
279 
280 /*******************************************************************************
281  *
282  *     Name:        elm_20node_brick_dndu_fvalue( double *,double,double,double )
283  *
284  *     Purpose:     return value of a first partial derivate in (v) of a
285  *                  quantity given on nodes at point (u,v).
286  *                  Use trough (element_type_t *) structure.
287  *
288  *
289  *     Parameters:
290  *
291  *         Input:  (double *) quantity values at nodes
292  *                 (double u,double v,double w) point where values are evaluated
293  *
294  *         Output:  none
295  *
296  *   Return value:  quantity value
297  *
298  ******************************************************************************/
elm_20node_brick_dndu_fvalue(double * F,double u,double v,double w)299 static double elm_20node_brick_dndu_fvalue(double *F,double u,double v,double w)
300 {
301      double R=0.0,vw=v*w,u2=2*u,u2v=u2*v,u2w=u2*w,vv=v*v,ww=w*w,u2vw=u2*vw,vvw=vv*w,vww=v*ww;
302      int i;
303 
304      for( i=0; i<20; i++ )
305      {
306          R += F[i]*( N[i][1]       +
307                      N[i][4]*v     +
308                      N[i][5]*w     +
309                      N[i][7]*vw    +
310                      N[i][8]*u2    +
311                      N[i][11]*u2v  +
312                      N[i][12]*u2w  +
313                      N[i][13]*vv   +
314                      N[i][14]*ww   +
315                      N[i][17]*u2vw +
316                      N[i][18]*vvw  +
317                      N[i][19]*vww  );
318      }
319 
320      return R;
321 }
322 /*******************************************************************************
323  *
324  *     Name:        elm_20node_brick_dndv_fvalue( double *,double,double,double )
325  *
326  *     Purpose:     return value of a first partial derivate in (v) of a
327  *                  quantity given on nodes at point (u,v,w).
328  *                  Use trough (element_type_t *) structure.
329  *
330  *
331  *     Parameters:
332  *
333  *         Input:  (double *) quantity values at nodes
334  *                 (double u,double v,double w) point where values are evaluated
335  *
336  *         Output:  none
337  *
338  *   Return value:  quantity value
339  *
340  ******************************************************************************/
elm_20node_brick_dndv_fvalue(double * F,double u,double v,double w)341 static double elm_20node_brick_dndv_fvalue(double *F,double u,double v,double w)
342 {
343      double R=0.0,uw=u*w,v2=2*v,uu=u*u,uv2=u*v2,v2w=v2*w,ww=w*w,uuw=uu*w,uv2w=uw*v2,uww=u*ww;
344      int i;
345 
346      for( i=0; i<20; i++ )
347      {
348          R += F[i]*( N[i][2]       +
349                      N[i][4]*u     +
350                      N[i][6]*w     +
351                      N[i][7]*uw    +
352                      N[i][9]*v2    +
353                      N[i][11]*uu   +
354                      N[i][13]*uv2  +
355                      N[i][15]*v2w  +
356                      N[i][16]*ww   +
357                      N[i][17]*uuw  +
358                      N[i][18]*uv2w +
359                      N[i][19]*uww  );
360      }
361 
362      return R;
363 }
364 
365 /*******************************************************************************
366  *
367  *     Name:        elm_20node_brick_dndw_fvalue( double *,double,double,double )
368  *
369  *     Purpose:     return value of a first partial derivate in (w) of a
370  *                  quantity given on nodes at point (u,v,w)
371  *                  Use trough (element_type_t *) structure.
372  *
373  *
374  *     Parameters:
375  *
376  *         Input:  (double *) quantity values at nodes
377  *                 (double u,double v,double w) point where values are evaluated
378  *
379  *         Output:  none
380  *
381  *   Return value:  quantity value
382  *
383  ******************************************************************************/
elm_20node_brick_dndw_fvalue(double * F,double u,double v,double w)384 static double elm_20node_brick_dndw_fvalue(double *F,double u,double v,double w)
385 {
386      double R=0.0,uv=u*v,w2=2*w,uu=u*u,uw2=u*w2,vv=v*v,vw2=v*w2,uuv=uu*v,uvv=u*vv,uvw2=uv*w2;
387      int i;
388 
389      for( i=0; i<20; i++ )
390      {
391          R += F[i]*( N[i][3]       +
392                      N[i][5]*u     +
393                      N[i][6]*v     +
394                      N[i][7]*uv    +
395                      N[i][10]*w2   +
396                      N[i][12]*uu   +
397                      N[i][14]*uw2  +
398                      N[i][15]*vv   +
399                      N[i][16]*vw2  +
400                      N[i][17]*uuv  +
401                      N[i][18]*uvv  +
402                      N[i][19]*uvw2 );
403      }
404 
405      return R;
406 }
407 
408 
409 /*******************************************************************************
410  *
411  *     Name:        elm_20node_brick_point_inside(
412  *                         double *nx,double *ny,double *nz,
413  *                         double px, double py, double pz,
414  *                         double *u,double *v,double *w )
415  *
416  *     Purpose:     Find if point (px,py,pz) is inside the element, and return
417  *                  element coordinates of the point.
418  *
419  *     Parameters:
420  *
421  *         Input:   (double *) nx,ny,nz node coordinates
422  *                  (double) px,py,pz point to consider
423  *
424  *         Output:  (double *) u,v,w point in element coordinates if inside
425  *
426  *   Return value:  in/out status
427  *
428  * NOTES: TODO: FIX THIS
429  *        trivial for this one...
430  *
431  ******************************************************************************/
elm_20node_brick_point_inside(double * nx,double * ny,double * nz,double px,double py,double pz,double * u,double * v,double * w)432 int elm_20node_brick_point_inside
433    (
434                  double *nx, double *ny, double *nz,
435         double px, double py, double pz, double *u,double *v,double *w
436    )
437 {
438     return elm_8node_brick_point_inside( nx,ny,nz,px,py,pz,u,v,w );
439 }
440 
441 /*******************************************************************************
442  *
443  *     Name:        elm_20node_brick_isoline
444  *
445  *     Purpose:     Extract a iso line from triangle with given threshold
446  *
447  *     Parameters:
448  *
449  *         Input:   (double) K, contour threshold
450  *                  (double *) F, contour quantity
451  *                  (double *) C, color quantity
452  *                  (double *) X,Y,Z vertex coords.
453  *
454  *         Output:  (line_t *)  place to store the line
455  *
456  *   Return value:  number of lines generated (0,...,144)
457  *
458  ******************************************************************************/
elm_20node_brick_isoline(double K,double * F,double * C,double * X,double * Y,double * Z,line_t * Line)459 static int elm_20node_brick_isoline
460   (
461      double K, double *F, double *C,double *X,double *Y,double *Z,line_t *Line
462   )
463 {
464     double f[8],c[8],x[8],y[8],z[8];
465 
466     int i, j, k, n=0, above=0;
467 
468     for( i=0; i<20; i++ ) above += F[i]>K;
469     if ( above == 0 || above == 20 ) return 0;
470 
471     for( i=0; i<6; i++ )
472     {
473         for( j=0; j<8; j++ )
474         {
475             k = ElmBrickFace[i][j];
476             f[j] = F[k];
477             c[j] = C[k];
478             x[j] = X[k];
479             y[j] = Y[k];
480             z[j] = Z[k];
481         }
482         n += elm_8node_quad_isoline( K,f,c,x,y,z,&Line[n] );
483     }
484 
485     return n;
486 }
487 
488 
489 /*******************************************************************************
490  *
491  *     Name:        elm_20node_brick_isosurface(
492  *                         double *nx,double *ny,double *nz,
493  *                         double px, double py, double pz,
494  *                         double *u,double *v,double *w )
495  *
496  *     Purpose:     Find if point (px,py,pz) is inside the element, and return
497  *                  element coordinates of the point.
498  *
499  *     Parameters:
500  *
501  *         Input:   (double *) nx,ny,nz node coordinates
502  *                  (double) px,py,pz point to consider
503  *
504  *         Output:  (double *) u,v,w point in element coordinates if inside
505  *
506  *   Return value:  in/out status
507  *
508  * NOTES: TODO: FIX THIS
509  *
510  ******************************************************************************/
elm_20node_brick_isosurface(double K,double * F,double * C,double * X,double * Y,double * Z,double * U,double * V,double * W,polygon_t * Polygon)511 int elm_20node_brick_isosurface
512    (
513        double  K,double *F,double *C,
514        double *X,double *Y,double *Z,
515        double *U,double *V,double *W,
516        polygon_t *Polygon
517    )
518 {
519     double f[8],c[8],x[8],y[8],z[8],u[8],v[8],w[8];
520     int i,j,k, n=0, above = 0;
521 
522     for( i=0; i<20; i++ ) above += F[i]>K;
523     if ( above == 0 || above == 20 ) return 0;
524 
525     n += elm_8node_brick_isosurface( K,F,C,X,Y,Z,U,V,W,Polygon );
526     return n;
527 }
528 
529 
530 /******************************************************************************
531  *
532  *     Name:        elm_20node_brick_initialize( )
533  *
534  *     Purpose:     Register the element type
535  *
536  *     Parameters:
537  *
538  *         Input:  (char *) description of the element
539  *                 (int)    numeric code for the element
540  *
541  *         Output:  Global list of element types is modified
542  *
543  *   Return value:  malloc() success
544  *
545  ******************************************************************************/
elm_20node_brick_initialize()546 int elm_20node_brick_initialize()
547 {
548      static char *Name = "ELM_20NODE_BRICK";
549 
550      element_type_t ElementDef;
551 
552      elm_20node_brick_shape_functions();
553 
554      ElementDef.ElementName = Name;
555      ElementDef.ElementCode = 820;
556 
557      ElementDef.NumberOfNodes = 20;
558 
559      ElementDef.NodeU = NodeU;
560      ElementDef.NodeV = NodeV;
561      ElementDef.NodeW = NodeW;
562 
563      ElementDef.PartialU = (double (*)())elm_20node_brick_dndu_fvalue;
564      ElementDef.PartialV = (double (*)())elm_20node_brick_dndv_fvalue;
565      ElementDef.PartialW = (double (*)())elm_20node_brick_dndw_fvalue;
566 
567      ElementDef.FunctionValue = (double (*)())elm_20node_brick_fvalue;
568      ElementDef.Triangulate   = (int (*)())elm_20node_brick_triangulate;
569      ElementDef.PointInside   = (int (*)())elm_20node_brick_point_inside;
570      ElementDef.IsoLine       = (int (*)())elm_20node_brick_isoline;
571      ElementDef.IsoSurface    = (int (*)())elm_20node_brick_isosurface;
572 
573      return elm_add_element_type( &ElementDef ) ;
574 }
575