spherical_advection_diffusion_elements.cc
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1// LIC// ====================================================================
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3// LIC// multi-physics finite-element library, available
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25// LIC//====================================================================
26// Non-inline functions for Advection Diffusion elements in a spherical
27// coordinate system
29
30namespace oomph
31{
32 /// 2D Steady Axisymmetric Advection Diffusion elements
33
34 /// Default value for Peclet number
36
37
38 //======================================================================
39 /// Compute element residual Vector and/or element Jacobian matrix
40 ///
41 /// flag=1: compute both
42 /// flag=0: compute only residual Vector
43 ///
44 /// Pure version without hanging nodes
45 //======================================================================
48 Vector<double>& residuals,
49 DenseMatrix<double>& jacobian,
50 DenseMatrix<double>& mass_matrix,
51 unsigned flag)
52 {
53 // Find out how many nodes there are
54 const unsigned n_node = nnode();
55
56 // Get the nodal index at which the unknown is stored
57 const unsigned u_nodal_index = u_index_spherical_adv_diff();
58
59 // Set up memory for the shape and test functions
60 Shape psi(n_node), test(n_node);
61 DShape dpsidx(n_node, 2), dtestdx(n_node, 2);
62
63 // Set the value of n_intpt
64 const unsigned n_intpt = integral_pt()->nweight();
65
66 // Set the Vector to hold local coordinates
68
69 // Get Physical Variables from Element
70 const double scaled_peclet = pe();
71
72 // Get peclet number multiplied by Strouhal number
73 const double scaled_peclet_st = pe_st();
74
75 // Integers used to store the local equation number and local unknown
76 // indices for the residuals and jacobians
77 int local_eqn = 0, local_unknown = 0;
78
79 // Loop over the integration points
80 for (unsigned ipt = 0; ipt < n_intpt; ipt++)
81 {
82 // Assign values of s
83 for (unsigned i = 0; i < 2; i++) s[i] = integral_pt()->knot(ipt, i);
84
85 // Get the integral weight
86 double w = integral_pt()->weight(ipt);
87
88 // Call the derivatives of the shape and test functions
90 ipt, psi, dpsidx, test, dtestdx);
91
92 // Premultiply the weights and the Jacobian
93 double W = w * J;
94
95 // Calculate local values of the solution and its derivatives
96 // Allocate
97 double interpolated_u = 0.0;
98 double dudt = 0.0;
100 Vector<double> interpolated_dudx(2, 0.0);
101
102 // Calculate function value and derivatives:
103 //-----------------------------------------
104 // Loop over nodes
105 for (unsigned l = 0; l < n_node; l++)
106 {
107 // Get the value at the node
108 double u_value = raw_nodal_value(l, u_nodal_index);
109 interpolated_u += u_value * psi(l);
110 dudt += du_dt_spherical_adv_diff(l) * psi(l);
111 // Loop over the two coordinates directions
112 for (unsigned j = 0; j < 2; j++)
113 {
114 interpolated_x[j] += raw_nodal_position(l, j) * psi(l);
115 interpolated_dudx[j] += u_value * dpsidx(l, j);
116 }
117 }
118
119 // Get source function
120 //-------------------
121 double source;
123
124
125 // Get wind
126 //--------
127 Vector<double> wind(3);
129
130 // r is the first position component
131 double r = interpolated_x[0];
132 // theta is the second position component
133 double sin_th = sin(interpolated_x[1]);
134 // dS is the area weighting
135 double dS = r * r * sin_th;
136
137 // TEMPERATURE EQUATION (Neglected viscous dissipation)
138 // Assemble residuals and Jacobian
139 //--------------------------------
140
141 // Loop over the test functions
142 for (unsigned l = 0; l < n_node; l++)
143 {
144 // Set the local equation number
145 local_eqn = nodal_local_eqn(l, u_nodal_index);
146
147 /*IF it's not a boundary condition*/
148 if (local_eqn >= 0)
149 {
150 // Add body force/source term
151 residuals[local_eqn] -=
152 (scaled_peclet_st * dudt + source) * dS * test(l) * W;
153
154 // The Advection Diffusion bit itself
155 residuals[local_eqn] -=
156 // radial terms
157 (dS * interpolated_dudx[0] *
158 (scaled_peclet * wind[0] * test(l) + dtestdx(l, 0)) +
159 // azimuthal terms
160 (sin_th * interpolated_dudx[1] *
161 (r * scaled_peclet * wind[1] * test(l) + dtestdx(l, 1)))) *
162 W;
163
164
165 // Calculate the jacobian
166 //-----------------------
167 if (flag)
168 {
169 // Loop over the velocity shape functions again
170 for (unsigned l2 = 0; l2 < n_node; l2++)
171 {
172 // Set the number of the unknown
173 local_unknown = nodal_local_eqn(l2, u_nodal_index);
174
175 // If at a non-zero degree of freedom add in the entry
176 if (local_unknown >= 0)
177 {
178 // Mass matrix term
179 jacobian(local_eqn, local_unknown) -=
180 scaled_peclet_st * test(l) * psi(l2) *
181 node_pt(l2)->time_stepper_pt()->weight(1, 0) * dS * W;
182
183 // add the mass matrix term
184 if (flag == 2)
185 {
186 mass_matrix(local_eqn, local_unknown) +=
187 scaled_peclet_st * test(l) * psi(l2) * dS * W;
188 }
189
190 // Assemble Jacobian term
191 jacobian(local_eqn, local_unknown) -=
192 // radial terms
193 (dS * dpsidx(l2, 0) *
194 (scaled_peclet * wind[0] * test(l) + dtestdx(l, 0)) +
195 // azimuthal terms
196 (sin_th * dpsidx(l2, 1) *
197 (r * scaled_peclet * wind[1] * test(l) + dtestdx(l, 1)))) *
198 W;
199 }
200 }
201 }
202 }
203 }
204
205
206 } // End of loop over integration points
207 }
208
209
210 //======================================================================
211 /// Self-test: Return 0 for OK
212 //======================================================================
213 // template <unsigned DIM>
215 {
216 bool passed = true;
217
218 // Check lower-level stuff
219 if (FiniteElement::self_test() != 0)
220 {
221 passed = false;
222 }
223
224 // Return verdict
225 if (passed)
226 {
227 return 0;
228 }
229 else
230 {
231 return 1;
232 }
233 }
234
235
236 //======================================================================
237 /// Output function:
238 ///
239 /// r,z,u,w_r,w_z
240 ///
241 /// nplot points in each coordinate direction
242 //======================================================================
244 const unsigned& nplot)
245 {
246 // Vector of local coordinates
247 Vector<double> s(2);
248
249 // Tecplot header info
250 outfile << tecplot_zone_string(nplot);
251
252 // Loop over plot points
253 unsigned num_plot_points = nplot_points(nplot);
254 for (unsigned iplot = 0; iplot < num_plot_points; iplot++)
255 {
256 // Get local coordinates of plot point
257 get_s_plot(iplot, nplot, s);
258
259 // Get Eulerian coordinate of plot point
260 Vector<double> x(2);
261 interpolated_x(s, x);
262
263 for (unsigned i = 0; i < 2; i++)
264 {
265 outfile << x[i] << " ";
266 }
267
268 // Convert to Cartesians
269 outfile << x[0] * sin(x[1]) << " " << x[0] * cos(x[1]) << " ";
270 // Output concentration
271 outfile << this->interpolated_u_spherical_adv_diff(s) << " ";
272
273 // Get the wind
274 Vector<double> wind(2);
275 // Dummy ipt argument needed... ?
276 unsigned ipt = 0;
277 get_wind_spherical_adv_diff(ipt, s, x, wind);
278 for (unsigned i = 0; i < 2; i++)
279 {
280 outfile << wind[i] << " ";
281 }
282 outfile << std::endl;
283 }
284
285 // Write tecplot footer (e.g. FE connectivity lists)
286 write_tecplot_zone_footer(outfile, nplot);
287 }
288
289
290 //======================================================================
291 /// C-style output function:
292 ///
293 /// r,z,u
294 ///
295 /// nplot points in each coordinate direction
296 //======================================================================
297 // template <unsigned DIM>
299 const unsigned& nplot)
300 {
301 // Vector of local coordinates
302 Vector<double> s(2);
303
304 // Tecplot header info
305 fprintf(file_pt, "%s", tecplot_zone_string(nplot).c_str());
306
307 // Loop over plot points
308 unsigned num_plot_points = nplot_points(nplot);
309 for (unsigned iplot = 0; iplot < num_plot_points; iplot++)
310 {
311 // Get local coordinates of plot point
312 get_s_plot(iplot, nplot, s);
313
314 for (unsigned i = 0; i < 2; i++)
315 {
316 fprintf(file_pt, "%g ", interpolated_x(s, i));
317 }
318 // Write Cartesian coordinates
319 double r = interpolated_x(s, 0);
320 double theta = interpolated_x(s, 1);
321 fprintf(file_pt, "%g %g ", r * sin(theta), r * cos(theta));
322
323 fprintf(file_pt, "%g \n", interpolated_u_spherical_adv_diff(s));
324 }
325
326 // Write tecplot footer (e.g. FE connectivity lists)
327 write_tecplot_zone_footer(file_pt, nplot);
328 }
329
330 //======================================================================
331 /// Output exact solution
332 ///
333 /// Solution is provided via function pointer.
334 /// Plot at a given number of plot points.
335 ///
336 /// r,z,u_exact
337 //======================================================================
338 // template <unsigned DIM>
340 std::ostream& outfile,
341 const unsigned& nplot,
343 {
344 // Vector of local coordinates
345 Vector<double> s(2);
346
347 // Vector for coordintes
348 Vector<double> x(2);
349
350 // Tecplot header info
351 outfile << tecplot_zone_string(nplot);
352
353 // Exact solution Vector (here a scalar)
354 Vector<double> exact_soln(1);
355
356 // Loop over plot points
357 unsigned num_plot_points = nplot_points(nplot);
358 for (unsigned iplot = 0; iplot < num_plot_points; iplot++)
359 {
360 // Get local coordinates of plot point
361 get_s_plot(iplot, nplot, s);
362
363 // Get x position as Vector
364 interpolated_x(s, x);
365
366 // Get exact solution at this point
367 (*exact_soln_pt)(x, exact_soln);
368
369 // Output x,y,...,u_exact
370 for (unsigned i = 0; i < 2; i++)
371 {
372 outfile << x[i] << " ";
373 }
374 outfile << exact_soln[0] << std::endl;
375 }
376
377 // Write tecplot footer (e.g. FE connectivity lists)
378 write_tecplot_zone_footer(outfile, nplot);
379 }
380
381
382 //======================================================================
383 /// Validate against exact solution
384 ///
385 /// Solution is provided via function pointer.
386 /// Plot error at a given number of plot points.
387 ///
388 //======================================================================
389 // template <unsigned DIM>
391 std::ostream& outfile,
393 double& error,
394 double& norm)
395 {
396 // Initialise
397 error = 0.0;
398 norm = 0.0;
399
400 // Vector of local coordinates
401 Vector<double> s(2);
402
403 // Vector for coordintes
404 Vector<double> x(2);
405
406 // Find out how many nodes there are in the element
407 unsigned n_node = nnode();
408
409 Shape psi(n_node);
410
411 // Set the value of n_intpt
412 unsigned n_intpt = integral_pt()->nweight();
413
414 // Tecplot header info
415 outfile << "ZONE" << std::endl;
416
417 // Exact solution Vector (here a scalar)
418 Vector<double> exact_soln(1);
419
420 // Loop over the integration points
421 for (unsigned ipt = 0; ipt < n_intpt; ipt++)
422 {
423 // Assign values of s
424 for (unsigned i = 0; i < 2; i++)
425 {
426 s[i] = integral_pt()->knot(ipt, i);
427 }
428
429 // Get the integral weight
430 double w = integral_pt()->weight(ipt);
431
432 // Get jacobian of mapping
433 double J = J_eulerian(s);
434
435 // Premultiply the weights and the Jacobian
436 double W = w * J;
437
438 // Get x position as Vector
439 interpolated_x(s, x);
440
441 // Get FE function value
443
444 // Get exact solution at this point
445 (*exact_soln_pt)(x, exact_soln);
446
447 // Output x,y,...,error
448 for (unsigned i = 0; i < 2; i++)
449 {
450 outfile << x[i] << " ";
451 }
452 outfile << exact_soln[0] << " " << exact_soln[0] - u_fe << std::endl;
453
454 // Add to error and norm
455 norm += exact_soln[0] * exact_soln[0] * W;
456 error += (exact_soln[0] - u_fe) * (exact_soln[0] - u_fe) * W;
457 }
458 }
459
460
461 //======================================================================
462 // Set the data for the number of Variables at each node
463 //======================================================================
464 template<unsigned NNODE_1D>
466 1;
467
468 //====================================================================
469 // Force build of templates
470 //====================================================================
471
475
476
477} // namespace oomph
static char t char * s
Definition: cfortran.h:568
cstr elem_len * i
Definition: cfortran.h:603
A Class for the derivatives of shape functions The class design is essentially the same as Shape,...
Definition: shape.h:278
TimeStepper *& time_stepper_pt()
Return the pointer to the timestepper.
Definition: nodes.h:238
virtual double J_eulerian(const Vector< double > &s) const
Return the Jacobian of mapping from local to global coordinates at local position s.
Definition: elements.cc:4103
Integral *const & integral_pt() const
Return the pointer to the integration scheme (const version)
Definition: elements.h:1963
virtual std::string tecplot_zone_string(const unsigned &nplot) const
Return string for tecplot zone header (when plotting nplot points in each "coordinate direction")
Definition: elements.h:3161
virtual double interpolated_x(const Vector< double > &s, const unsigned &i) const
Return FE interpolated coordinate x[i] at local coordinate s.
Definition: elements.cc:3962
int nodal_local_eqn(const unsigned &n, const unsigned &i) const
Return the local equation number corresponding to the i-th value at the n-th local node.
Definition: elements.h:1432
unsigned nnode() const
Return the number of nodes.
Definition: elements.h:2210
void(* SteadyExactSolutionFctPt)(const Vector< double > &, Vector< double > &)
Function pointer for function that computes vector-valued steady "exact solution" as .
Definition: elements.h:1759
virtual void get_s_plot(const unsigned &i, const unsigned &nplot, Vector< double > &s, const bool &shifted_to_interior=false) const
Get cector of local coordinates of plot point i (when plotting nplot points in each "coordinate direc...
Definition: elements.h:3148
virtual unsigned nplot_points(const unsigned &nplot) const
Return total number of plot points (when plotting nplot points in each "coordinate direction")
Definition: elements.h:3186
Node *& node_pt(const unsigned &n)
Return a pointer to the local node n.
Definition: elements.h:2175
double raw_nodal_value(const unsigned &n, const unsigned &i) const
Return the i-th value stored at local node n but do NOT take hanging nodes into account.
Definition: elements.h:2576
double raw_nodal_position(const unsigned &n, const unsigned &i) const
Return the i-th coordinate at local node n. Do not use the hanging node representation....
Definition: elements.cc:1686
virtual void write_tecplot_zone_footer(std::ostream &outfile, const unsigned &nplot) const
Add tecplot zone "footer" to output stream (when plotting nplot points in each "coordinate direction"...
Definition: elements.h:3174
virtual unsigned self_test()
Self-test: Check inversion of element & do self-test for GeneralisedElement. Return 0 if OK.
Definition: elements.cc:4440
virtual double knot(const unsigned &i, const unsigned &j) const =0
Return local coordinate s[j] of i-th integration point.
virtual unsigned nweight() const =0
Return the number of integration points of the scheme.
virtual double weight(const unsigned &i) const =0
Return weight of i-th integration point.
//////////////////////////////////////////////////////////////////////// ////////////////////////////...
A Class for shape functions. In simple cases, the shape functions have only one index that can be tho...
Definition: shape.h:76
virtual void get_source_spherical_adv_diff(const unsigned &ipt, const Vector< double > &x, double &source) const
Get source term at (Eulerian) position x. This function is virtual to allow overloading in multi-phys...
double interpolated_u_spherical_adv_diff(const Vector< double > &s) const
Return FE representation of function value u(s) at local coordinate s.
virtual double dshape_and_dtest_eulerian_at_knot_spherical_adv_diff(const unsigned &ipt, Shape &psi, DShape &dpsidx, Shape &test, DShape &dtestdx) const =0
Shape/test functions and derivs w.r.t. to global coords at integration point ipt; return Jacobian of ...
void output_fct(std::ostream &outfile, const unsigned &nplot, FiniteElement::SteadyExactSolutionFctPt exact_soln_pt)
Output exact soln: r,z,u_exact at nplot^2 plot points.
void output(std::ostream &outfile)
Output with default number of plot points.
double du_dt_spherical_adv_diff(const unsigned &n) const
du/dt at local node n. Uses suitably interpolated value for hanging nodes.
const double & pe_st() const
Peclet number multiplied by Strouhal number.
void compute_error(std::ostream &outfile, FiniteElement::SteadyExactSolutionFctPt exact_soln_pt, double &error, double &norm)
Get error against and norm of exact solution.
virtual unsigned u_index_spherical_adv_diff() const
Return the index at which the unknown value is stored. The default value, 0, is appropriate for singl...
static double Default_peclet_number
Static default value for the Peclet number.
virtual void fill_in_generic_residual_contribution_spherical_adv_diff(Vector< double > &residuals, DenseMatrix< double > &jacobian, DenseMatrix< double > &mass_matrix, unsigned flag)
Add the element's contribution to its residual vector only (if flag=and/or element Jacobian matrix.
virtual void get_wind_spherical_adv_diff(const unsigned &ipt, const Vector< double > &s, const Vector< double > &x, Vector< double > &wind) const
Get wind at (Eulerian) position x and/or local coordinate s. This function is virtual to allow overlo...
virtual double weight(const unsigned &i, const unsigned &j) const
Access function for j-th weight for the i-th derivative.
Definition: timesteppers.h:594
//////////////////////////////////////////////////////////////////// ////////////////////////////////...