FreeHyTE

The FreeHyTE Project is aimed at creating a unified computer platform for the implementation of hybrid and Trefftz finite element formulations for elliptic, parabolic and hyperbolic (initial) boundary value problems.

The platform takes advantage of the uniform structure of the hybrid formulations regardless of the specific problem that is being solved, to accommodate the solution of physically different problems with minimal coding effort.

The entire computational framework is implemented in the MATLABTM environment. It features an efficient topological description of the mesh, obtained either with a mesh generator developed locally or with a mesh generator built in MATLAB, together with an integrated matrix storage scheme. Data input contains a complete description of the geometry, material properties, initial and boundary conditions and is organised in data structures common to the different finite element formulations. The common mesh generators and data structures enhance the extensibility of the computational platform to new applications since only application specific features need be programmed from scratch. To enable the use of the computational tool by inexperienced analysts, the platform includes all the required pre- and post-processing tools, and features a user-friendly GUI, Developer's Guide, User's and Installation Manuals.

FreeHyTE releases

FreeHyTE is a collection of various pieces of software developed by myself, together with Ildi Cismasiu and a number of MSc students of ours, which are currently in various phases of their development. Beta versions of the applications that are considered to be sufficiently mature are deployed here for third party testing. All modules are open-source and published under a GNU-GPL licence to enable subsequent expansions by external developers.

Since these are Beta versions, they may (will!) present errors, especially on Matlab versions different from mine. Any feedback and error reporting is greatly appreciated! Please e-mail me directly.

FreeHyTE Developer's Manual

FreeHyTE - theoretical bases and developer's manual, CERIS, Instituto Superior TĂ©cnico, Universidade de Lisboa, 2017

Releasing the Beta version 1.2.0 of the direct Boundary Methods solver for 2D Laplace and Helmholtz boundary value problems, subjected to Dirichlet, Neumann and (generalized) Robin boundary conditions. FreeHyTE - direct Boundary Methods offers three types of solvers, namely direct Boundary Element Method, direct Method of Fundamental Solutions and direct Trefftz-Herrera Method. It is the first extension of FreeHyTE into boundary methods. The version is released along with a supporting User's Guide.

File list:

  • FreeHyTE - direct Boundary Methods.zip: ZIP archive containing the source *.m files and examples of applications

  • UsersManual_DBM.pdf: User's Guide

FreeHyTE - direct Boundary Methods is on GitLab! Check it out here and contribute!

Releasing the Beta version 1.3.0 of the displacement-based hybrid-Trefftz finite element solver for transient problems defined on solid (single-phase) media. The version is released along with a supporting MSc Thesis and a User's Guide.


File list:

  • FreeHyTE - Solid Transient.zip: ZIP archive containing the source *.m files

  • UsersManual_SolidTransient: User's Guide

  • Supporting MSc thesis

FreeHyTE - Solid Transient is on GitLab! Check it out here and contribute!

Releasing the Beta version 1.3.2 of the displacement-based hybrid-Trefftz finite element solver for transient problems defined on unsaturated (triphasic) porous media. The version is released along with a supporting PhD Thesis and a User's Guide.


File list:

  • FreeHyTE - Triphasic Transient.zip: ZIP archive containing the source *.m files

  • UsersManual_TriphasicTransient: User's Guide

  • Supporting PhD thesis

FreeHyTE-Triphasic Transient is on GitLab! Check it out here and contribute!

Releasing the Beta version 1.3.3 of the displacement-based hybrid-Trefftz finite element solver for transient problems defined on saturated (biphasic) porous media. The version is released along with a supporting PhD Thesis, an Installation Guide and a User's Guide.


File list:

  • FreeHyTE - Biphasic Transient.mlappinstall: Matlab App installer tested on R2016b

  • FreeHyTE - Biphasic Transient.zip: ZIP archive containing the source *.m files, to be used in alternative to the Apps or if the app installation fails on some Matlab version

  • InstallationManual_BiphasicTransient.pdf: Installation Manual

  • UsersManual_BiphasicTransient: User's Guide

  • Supporting PhD thesis

FreeHyTE-Biphasic Transient is on GitLab! Check it out here and contribute!

Releasing the Beta version 1.2.2 of the temperature-based hybrid-Trefftz finite element solver for transient heat diffusion problems, and non-homogeneous parabolic boundary value problems, in general. The version is released along with a supporting MSc Thesis (in Portuguese), an Installation Guide and and a User's Guide.


File list:

  • FreeHyTE - Transient Heat (2016).mlappinstall: Matlab App installer tested on R2016a

  • FreeHyTE - Transient Heat.zip: ZIP archive containing the source *.m files, to be used in alternative to the Apps or if the app installation fails on some Matlab version

  • InstallationManual_TransientHeat.pdf: Installation Manual

  • UsersManual_TransientHeat.pdf: User's Guide

FreeHyTE-Transient Heat is on GitHub! Check it out here and contribute!

Releasing the Beta version 1.2.1 of the stress-based hybrid-Trefftz finite element solver for elastostatic plane stress and plane strain structural problems. The version is released along with a supporting MSc Thesis (in Portuguese), an Installation Guide and and a User's Guide.


File list:

  • FreeHyTE - Structural HTS.mlappinstall: Matlab App installer tested on R2014b, R2015a and R2016a

  • FreeHyTE - Structural HTS.zip: ZIP archive containing the source *.m files, to be used in alternative to the Apps or if the app installation fails on some Matlab version

  • InstallationManual_StructHTS.pdf: Installation Manual

  • UsersManual_StructHTS.pdf: User's Guide

Releasing the Beta version 1.2.2 of the displacement-based hybrid-Trefftz finite element solver for elastostatic plane stress and plane strain structural problems. The version is released along with a supporting MSc Thesis (in Portuguese), an Installation Guide and and a User's Guide.

Because of legacy issues with the resizing and resolution of the GUIs, version 1.2.2 is only compatible with Matlab versions posterior to 2013b. A legacy version of the mlappinstall file, compatible with Matlab 2012 and 2013 was maintained (with its old, HYBRIS name), but it runs version 1.1.


File list:

  • HYBRIS - Structural HTD (2012).mlappinstall: Matlab App installer tested on R2012b and R2013a

  • FreeHyTE - Structural HTD (2016).mlappinstall: Matlab App installer tested on R2014b, R2015a and R2016a

  • FreeHyTE - Structural HTD.zip: ZIP archive containing the source *.m files, to be used in alternative to the Apps or if the app installation fails on some Matlab version

  • InstallationManual_StructHTD.pdf: Installation Manual

  • UsersManual_StructHTD.pdf: User's Guide

FreeHyTE-Structural HTD is on GitHub! Check it out here and contribute!

Releasing the Beta version 1.2.3 of the temperature-based hybrid-Trefftz finite element solver for steady-state heat conduction problems in 2D. The version is released along with a supporting MSc Thesis (in Portuguese), an Installation Guide and and a User's Guide.


Because of legacy issues with the resizing and resolution of the GUIs, version 1.2.3 is only compatible with Matlab versions posterior to 2013b. A legacy version of the mlappinstall file, compatible with Matlab 2012 was maintained (with its old, HYBRIS name), but it runs version 1.1.


File list:

  • HYBRIS - Heat HTTE (2012).mlappinstall: Matlab App installer tested on R2012b and R2013a

  • FreeHyTE - Heat HTTE (2016).mlappinstall: Matlab App installer tested on R2014b, R2015a and R2016a

  • FreeHyTE - Heat HTTE.zip: ZIP archive containing the source *.m files, to be used in alternative to the Apps or if the app installation fails on some Matlab version

  • InstallationManual_HeatHTTE.pdf: Installation Manual

  • UsersManual_HeatHTTE.pdf: User's Guide

FreeHyTE-HTTE is on GitHub! Check it out here and contribute!

Releasing the Beta version 1.2.1 of the hybrid-Trefftz finite element solver for non-homogeneous hyperbolic boundary value problems. The version is released along with the supporting theoretical paper and three video tutorials on how to install and use it.


Because of legacy issues with the resizing and resolution of the GUIs, version 1.2.1 is only compatible with Matlab versions posterior to 2013b. A legacy version of the mlappinstall file, compatible with Matlab 2012 was maintained (with its old, HYBRIS name), but it runs version 1.1.


File list:

  • HYBRIS - Hyperbolic BVP (2012).mlappinstall: Matlab App installer tested on R2012b

  • FreeHyTE - Hyperbolic BVP (2016).mlappinstall: Matlab App installer tested on R2014b, R2015a and R2016a

  • FreeHyTE - Hyperbolic BVP.zip: ZIP archive containing the source *.m files, to be used in alternative to the Apps or if the app installation fails on some Matlab version

  • Unpacking_Guide.mp4: video guide on unpacking the zip archive. For a guide on installing Matlab Apps, see this link

  • GUI_GUIDE_P1(2).mp4: video guides on using the program