- #FREE FDTD FOR FREE#
- #FREE FDTD UPDATE#
- #FREE FDTD SOFTWARE#
- #FREE FDTD LICENSE#
- #FREE FDTD WINDOWS#
#FREE FDTD UPDATE#
One method emulates exciting a geometry at discrete locations by applying a sampled waveform to the field update equation at one or more locations. In practice the cell size will often be smaller than this in order to resolve dimensions and features of the structure to be simulated such as the thickness of a substrate or the length of a wire.Īn excitation may be applied to an FDTD simulation in many different ways. A general rule of thumb sets the minimum resolution, and thus the upper frequency limit, at ten cells per wavelength. The cell size, the dimensions of the small box, is the most important constraint in any FDTD simulation since it determines not only the step size in time, but also the upper frequency limit for the calculation. Each small box shown in the figure represents one FDTD cell. By associating many cell edges with materials, a geometrical structure can be formed within the FDTD grid such as the dielectric sphere shown in Figure 2. Introducing other materials or other configurations is handled in a similar manner and each may be applied to either the electric or magnetic fields depending on the characteristics of the material. By joining numerous end-to-end cell edges defined as perfectly conducting material, a wire can be formed. For example, to add a perfectly conducting wire segment to a cell edge, the equation for computing the electric field can be replaced by simply setting the field to zero since the electric field in a perfect conductor is identically zero. Within the mesh, materials such as conductors or dielectrics can be added by changing the equations for computing the fields at given locations. Each cell will also have three magnetic fields originating on the faces of the cell adjacent to the common node of the electric fields as shown in Figure 1. The electric fields at the other nine edges of the FDTD cell will belong to other, adjacent cells. Each FDTD cell will overlap edges and faces with its neighbors, so by convention each cell will have three electric fields that begin at a common node associated with it.
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Matlab toolboxes to easily handle input and output files ( Downloads).
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#FREE FDTD WINDOWS#
Source codes and various executables for Windows and Linux ( Downloads).User's guides for the various available versions ( Downloads).SimSonic3D : 3D computations on a xyz cartesian mesh.SimSonic2D : 2D computations on a xy cartesian mesh.Currently, the available versions are the following : Dissipation is not taken into account in the versions available on this website. In short, SimSonic models propagation in both fluid and solid media, which can be anisotropic and heterogeneous. The various versions of SimSonic correspond to different characteristics in terms of spatial dimensions and symmetries, but are otherwise based on the same physical model. The objective of this website is to provide researchers/students/teachers involved in ultrasound propagation with mature versions of SimSonic. It is however a very general tool that can be applied to various situations involving ultrasound propagation in fluids and/or solids (biomedical imaging, non-destructive testing, photoacoustic imaging, etc.). So far, SimSonic has been used mostly for research involving ultrasound propagation in bone ( References). Since then, SimSonic has been developed by Emmanuel Bossy, now at Institut Langevin, CNRS- ESPCI ParisTech, Paris, France, and has regularly been enriched with new options and versions. The development of SimSonic was started in 2003 by Emmanuel Bossy during his PhD work at the Laboratoire d'Imagerie Paramétrique (CNRS-University Paris 6) in Paris, France.
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#FREE FDTD FOR FREE#
In exchange for free access to the SimSonic suite, the users are asked to make proper references, in their research publications or any other types of oral or written communications, to and to Bossy et al, JASA 115, 2314-2324, 2004 (see References).
#FREE FDTD LICENSE#
The SimSonic suite consists of several compiled programs and C source codes, free for use, under the GNU GPL license (please see Copyrights). It is intended as a tool for researchers, teachers and students communities.
#FREE FDTD SOFTWARE#
SimSonic is freely available 3rd party software suite for the simulation of ultrasound propagation, based on finite-difference time-domain (FDTD) computations of the elastodynamic equations.