plate.cc File Reference

#include "generic.h"
#include "shell.h"
#include "meshes/rectangular_quadmesh.h"

Classes
class	FlatPlate
	Flat plate in x-y plane. More...
class	FlatPlateMesh< ELEMENT >
class	PlateProblem< ELEMENT >

Namespaces
	Global_Physical_Variables
	Global variables.

Functions
double &	Global_Physical_Variables::external_pressure ()
	Access function to value of external pressure. More...
void	Global_Physical_Variables::press_load (const Vector< double > &xi, const Vector< double > &x, const Vector< double > &N, Vector< double > &load)
	Load function: Perturbation pressure to force non-axisymmetric deformation. More...
int	main (int argc, char *argv[])
	Driver. More...

Variables
double	Global_Physical_Variables::Prescribed_z = 0.0
	Prescribed position of control point. More...

Function Documentation

main()

int main	(	int argc	,
		char *	argv[]
	)

Driver.

(pow(0.05,3)/12.0) << " "

{
 
 //Store command line arguments
 CommandLineArgs::setup(argc,argv);
 
 //Length of domain
 double L_x=10.0;
 double L_y=1.0;
 
 //Set up the problem
 PlateProblem<StorableShapeSolidElement<DiagHermiteShellElement> >
  problem(10,3,L_x,L_y);
 
 ofstream some_file;
 char filename[100];
 
 // Label for output
 DocInfo doc_info;
 
 // Output directory
 doc_info.set_directory("RESLT");
 
 //Open an output trace file
 sprintf(filename,"%s/trace.dat",doc_info.directory().c_str());
 ofstream trace_file(filename);
 trace_file << "VARIABLES=\"p_e_x_t\",\"z_ctrl\"" << std::endl;
 trace_file << "ZONE" << std::endl;
 
 //Gradually deflect the plate by decreasing the value of the prescribed
 //position 
 unsigned nstep=2;
 for(unsigned i=0;i<nstep;i++)
  {
   
   // Increase displacement
   Global_Physical_Variables::Prescribed_z -= 0.1;
   
   // Solve
   problem.newton_solve();   
   
   
   // Calculate exact solution for `string under tension' (applicable for
   // small wall thickness and pinned ends)
   
   // The tangent of the angle beta
   double tanbeta =-2.0*Global_Physical_Variables::Prescribed_z/L_x;
   
   double exact_pressure = 0.0;
   //If the plate has deformed, calculate the pressure required
   if(tanbeta!=0)
    {
     
     //Calculate the opening angle alpha
     double alpha = 2.0*atan(2.0*tanbeta/(1.0-tanbeta*tanbeta));
 
      // Jump back onto the main branch if alpha>180 degrees
     if (alpha<0) alpha+=2.0*MathematicalConstants::Pi;
     
     // Green strain:
     double gamma=0.5*(0.25*alpha*alpha/(sin(0.5*alpha)*sin(0.5*alpha))-1.0);
     
     //Calculate the exact pressure
     exact_pressure=Global_Physical_Variables::H*
      (Global_Physical_Variables::Sigma0+gamma)*alpha/L_x;
    } 
   
 
   //Output the pressure 
   trace_file 
    << Global_Physical_Variables::external_pressure() << " " 
    << Global_Physical_Variables::Prescribed_z  << " " 
    << exact_pressure << " "
    << std::endl;
   
   
   //Output the shape 
   sprintf(filename,"%s/plate%i.dat",doc_info.directory().c_str(),
           doc_info.number());
   some_file.open(filename);
   problem.mesh_pt()->output(some_file,15);
//    for (unsigned e=0;e<nelem;e++)
//     {
//      mesh_pt()->finite_element_pt(e)->output(some_file,15);
//     }
   some_file.close();
   
   // Increment counter for output files
   doc_info.number()++;
   
  }
 
 //Close the trace file
 trace_file.close();
 
}

References alpha, Eigen::bfloat16_impl::atan(), oomph::DocInfo::directory(), Global_Physical_Variables::external_pressure(), MergeRestartFiles::filename, mathsFunc::gamma(), Global_Physical_Variables::H, i, Global_Parameters::L_x, Global_Parameters::L_y, oomph::DocInfo::number(), BiharmonicTestFunctions2::Pi, Global_Physical_Variables::Prescribed_z, problem, oomph::DocInfo::set_directory(), Flag_definition::setup(), Global_Physical_Variables::Sigma0, and sin().