In contrast to conventional nozzles, special-purpose nozzles are often characterized by unconventional geometric configurations or are designed to operate under specific and complex inlet conditions. These unique features not only increase the dimensionality of the nozzle design space, but also significantly complicate the coupling mechanisms between nozzle geometry and the overall engine operating conditions. For conventional nozzles, the primary influence on overall engine performance is typically limited to variations in throat and exit areas. However, in the case of special-purpose nozzles, geometric parameters have a more intricate impact on the engine operating point. Additionally, the performance behavior of special-purpose nozzles under nonstandard inlet conditions diverges notably from that of conventional configurations, rendering it inappropriate to analyze engines equipped with such nozzles using conventional nozzle performance characteristics (Zhang 2005). Hence, the development of a coupled simulation model that integrates special-purpose nozzle behavior with complete engine system dynamics is essential for accurately evaluating their influence on overall engine performance.