文件
gprMax/docs/source/comparisons_analytical.rst
2017-01-26 17:19:40 +00:00

46 行
2.3 KiB
ReStructuredText

**********************
Analytical comparisons
**********************
This section presents comparisons between analytical solutions and modelled solutions using gprMax.
Hertzian dipole in free space
=============================
:download:`hertzian_dipole_fs.in <../../tests/models_basic/hertzian_dipole_fs/hertzian_dipole_fs.in>`
This example is of a Hertzian dipole, i.e. an additive source (electric current density), in free space.
.. literalinclude:: ../../tests/models_basic/hertzian_dipole_fs/hertzian_dipole_fs.in
:language: none
:linenos:
The function ``hertzian_dipole_fs``, which can be found in the ``analytical_solutions`` module in the ``tests`` sub-package, computes the analytical solution.
Results
-------
:numref:`hertzian_dipole_fs_results` shows the time history of the electric and magnetic field components of the modelled and analytical solutions. The responses completely overlap one another due to their similarity. Therefore, :numref:`hertzian_dipole_fs_results_diffs` shows the percentage differences between the modelled and analytical solutions.
.. _hertzian_dipole_fs_results:
.. figure:: ../../tests/models_basic/hertzian_dipole_fs_analytical/hertzian_dipole_fs_analytical.png
:width: 600 px
Time history of the electric and magnetic field components of the modelled and analytical solutions ('Ref', in this case, indicates solution calculated from theory).
.. _hertzian_dipole_fs_results_diffs:
.. figure:: ../../tests/models_basic/hertzian_dipole_fs_analytical/hertzian_dipole_fs_analytical_diffs.png
:width: 600 px
Percentage differences between the modelled and analytical solutions.
The match between the analytical and numerically modelled solutions is excellent. The maximum difference is approximately 1%, which is observed in the Ez field component (the same direction as the Hertzian dipole source). The other electric field components exhibit maximum differences of approximately 0.5%, and the magnetic field components 0.25%.
Half-wave dipole in free space
==============================
See the :ref:`section on antenna example models <example-wire-dipole>` for the simulated s11 parameter and input impedance of a half-wave dipole antenna in free space. The resonant frequency and input impedance from the model agree very well with the theoretical predictions for a half-wave dipole antenna.