adding von Mises stress routine + post_process to output

Author: mcarcana

src/common/m_variables_conversion.fpp

@@ -1032,6 +1032,14 @@ contains
                             qK_prim_vf(i)%sf(j, k, l) = qK_cons_vf(i)%sf(j, k, l)/rho_K
                         end do
                     end if
+#ifndef POST_PROCESS
+                    ! to save von Mises stress instead of elastic internal energy
+                    qK_prim_vf(xiend+1)%sf(j, k, l) = sqrt((3/2)*qK_prim_vf(1)%sf(j, k, l)**2 + &
+                                            2*qK_prim_vf(2)%sf(j, k, l)**2 + qK_prim_vf(3)%sf(j, k, l)**2 + &
+                                            2*qK_prim_vf(4)%sf(j, k, l)**2 + 2*qK_prim_vf(5)%sf(j, k, l)**2 + &
+                                            qK_prim_vf(6)%sf(j, k, l)**2)
+#endif
+                   end if
 
                     !$acc loop seq
                     do i = advxb, advxe

src/post_process/m_start_up.f90

@@ -385,6 +385,11 @@ subroutine s_save_data(t_step, varname, pres, c, H)
                     write (varname, '(A,I0)') 'xi', i
                     call s_write_variable_to_formatted_database_file(varname, t_step)
                 end if
+                if (prim_vars_wrt) then
+                    q_sf = q_prim_vf(xiend+1)%sf(j, k, l)
+                    write (varname, '(A,I0)') 'vonMises'
+                    call s_write_variable_to_formatted_database_file(varname, t_step)
+                end if
                 varname(:) = ' '
             end do
         end if