If you are working in ultrasound imaging, the below links will be very useful for your project or research

The k-wave toolbox:http://www.k-wave.org/

The FieldII Toolbox:https://field-ii.dk/

The CREANUIS Toolbox: https://www.creatis.insa-lyon.fr/site7/en/CREANUIS

The MUST Toolbox: https://www.biomecardio.com/MUST/

The Ultrasound Toolbox:https://www.ustb.no/

Simulation of Ultrasound signals on a 3D Brain model using K-Wave MATLAB toolbox: https://github.com/ManuelPalermo/BrainUltrasoundSimulation

FAST is an open-source cross-platform framework with the main goal of making it easier to do high-performance processing and visualization of medical images on heterogeneous systems utilizing both multi-core CPUs and GPUs. To achieve this, FAST use modern C++, OpenCL and OpenGL: https://github.com/smistad/FAST:

Open Source Software Defined Ultrasound Processing for Real-Time Applications:https://github.com/IFL-CAMP/supra

Ultrasim is an interactive, menu-oriented simulator for finding the sound field from transducers, primarily for medical ultrasound, but it can also be used for sonar and even loudspeakers:https://www.mn.uio.no/ifi/english/research/groups/dsb/resources/software/ultrasim/

The DREAM (Discrete REpresentation Array Modelling) toolbox is a free open source toolbox, for both Matlab and Octave , for simulating acoustic fields radiated from common ultrasonic transducer types and arbitrarily complicated ultrasonic transducers arrays. The toolbox is also provided with a user-friendly GUI (Matlab only):http://www.signal.uu.se/Toolbox/dream/index.shtml

FOCUS is a free cross-platform ultrasound simulation tool that quickly and accurately calculates pressure fields generated by single transducers and phased arrays. It claims better accuracy and speed than other simulation tools:https://www.egr.msu.edu/~fultras-web/index.php