Gas libraries contain blocks for the gas domain, organized into elements, sources, and sensors. Connect these blocks together just as you would assemble a physical system. Use these blocks, along with the blocks from other Foundation libraries and the add-on products, to model multidomain physical systems.
The Utilities library contains the Gas Properties (G) block, which lets you specify the gas properties in the connected circuit. This block provides the following levels of idealization: perfect gas, semiperfect gas, and real gas. For more information, see Modeling Gas Systems.