Download of Trishear3D 6.9 for Mac was on the developer's website when we last checked. We cannot confirm if there is a free download of this app available.
Please check the Mac app with an antivirus before launch as it is downloaded from the developer's website, and we cannot ensure that it is safe. This free Mac app is an intellectual property of Nestor Cardozo. The software lies within Education Tools, more precisely Science.
From the developer:
Trishear3D is a program to run three-dimensional forward trishear models. Trishear3D uses the pseudo3D and true 3D algorithms of Cristallini and Allmendinger (2001), and Cristallini et al. (2004), respectively.
Trishear3D is freeware, but only for academic purposes. If you want to use the program for consulting, please contact me.
You may want to check out more software for Mac, such as Trapcode Particular, Xfoil or DesignWorks Professional, which might be similar to Trishear3D.