A dynamic model of the Gas Turbine-Modular Helium Reactor core has been developed using the Simulink simulation program. The Simulink model utilizes a space-independent neutronics (point-kinetics) model along with a space-dependent heat transfer model of the core to simulate the short time reactor transients. The core model employs unique capabilities of the Simulink program to implement a user-friendly fully interactive environment to perform a variety of reactor transient scenarios.