T-MATS is an open-source Simulink library for use in modeling and simulation of thermodynamic systems. It provides a user friendly graphical MATLAB/Simulink-compatible toolbox along with tools to increase ease of model creation. It also includes a generic nonlinear solver that allows the designer to ensure that all conservation equations are respected at every time step.

Sample Simulation Architecture for a dynamic system.
The software has two main parts: a library of Simulink Blocks and a set of implementation scripts. The library consists of iterative solvers, generic model creation blocks, generic thermodynamic system blocks, and simple control logic blocks. The toolset includes scripts that auto-generate portions of the Simulink script to increase the user friendly aspect of the software.

The software features generic object-oriented building blocks representing a variety of thermodynamic and controls components. To use T-MATS, the user selects Simulink Blocks from the block library and simply drags them into the model. A built-in solver automatically scales to the appropriate number of state variables and uses a nonlinear optimization algorithm to solve the system at each point in time. Based on how the user has constructed the system, the simulation can return either steady-state results or operate in a transient manner. A number of pre-built examples are packaged with the software to allow users to quickly begin building their own models.

The simulation package is written in the industry-standard MATLAB/Simulink v2012b from MathWorks. It can be downloaded from: https://github.com/nasa/T-MATS/releases .

This work was done by Jeffryes Chapman, Ten-Huei Guo, Ryan May, Thomas Lavelle, and Jonathan Litt of Glenn Research Center.

Inquiries concerning rights for the commercial use of this invention should be addressed to NASA Glenn Research Center, Innovative Partnerships Office, Attn: Steven Fedor, Mail Stop 4–8, 21000 Brookpark Road, Cleveland, Ohio 44135. Refer to LEW-19165-1.