Preliminary development and validation of the thermal–hydraulic module for ADS system analysis code

• A thermal–hydraulic module for the ADS system analysis code was developed based on the fluid network technology. • The EBR-II benchmarks SHRT-17 and SHRT-45R were simulated to preliminarily validate the performance of the developed code. • The code enables comprehensive modeling of the primary system and supports transient thermal–hydraulic and safety analysis. To address the design and safety analysis requirements of China initiative Accelerator Driven System (CiADS), it is essential to develop a specialized system analysis code with independent intellectual property rights. Given the subcritical operation characteristics of the Accelerator Driven Subcritical System (ADS), this paper aims to preliminarily develop and validate the thermal–hydraulic module of the ADS system analysis code, facilitating comprehensive and flexible modeling of the primary thermal–hydraulic system through fluid network technology. To effectively solve the computational model, appropriate numerical methods were selected based on the specific characteristics of each individual model. Preliminary validation was conducted using the Experimental Breeder Reactor II (EBR-II) benchmark, including both protected and unprotected loss-of-flow transients, SHRT-17 and SHRT-45R. The results demonstrated reasonable agreement between the calculated and experimental values in terms of magnitude and trends, confirming the accuracy of the computational model. It is preliminary indicated that the code possesses the capability for transient thermal–hydraulic and safety analysis of the primary system, laying a solid foundation for the future development of a more comprehensive ADS system analysis code.