Abstract: The lead-bismuth-cooled fast reactor (LFR) employs lead-bismuth eutectic alloy as the reactor coolant, which is characterized by a high boiling point and chemical stability. It also offers outstanding safety advantages such as favorable neutronic properties and strong natural circulation capability. As such, it has been selected by the Generation IV International Forum (GIF) as one of the priority reactor types for development. Due to the large number of fuel assemblies and the geometrically complex core structure of the LFR, directly applying traditional computational fluid dynamics (CFD) methods to construct a high-fidelity geometric model of the entire core and generate control volume meshes for simulation would result in extremely high computational resource demands. To address this challenge, the Nuclear Thermal-Hydraulics Laboratory (NuTHeL) at Xi’an Jiaotong University has developed the CorTAF series of full-core three-dimensional thermal-hydraulic analysis codes based on an open-source CFD platform. These codes are capable of subchannel-level resolution and adaptable to various reactor types. In particular, CorTAF-LBE has been specifically tailored to the structural features of LFR cores. It enables high-fidelity coupled simulations of flow and heat transfer between fuel rods and coolant under limited computational resources. This makes it possible to accurately capture key thermal-hydraulic parameters under complex core operating conditions, thereby supporting structural optimization and safety margin assessment. NuTHeL has carried out extensive code verification and model improvement efforts based on experimental data and international benchmark problems. This has enabled CorTAF-LBE to perform core safety analyses under various accident conditions and to support cross-scale coupling calculations among multiple systems. For example, by embedding a flow blockage module, the code can reveal the characteristics of non-uniform temperature distribution induced by local blockages and assess the mitigating effects of inter-wrapper flow on thermal accumulation. It also elucidates the transient evolution of thermal stratification in the upper plenum at different shutdown stages, as well as the fine-scale distribution of surface thermal stresses in key locations and their impact on structural integrity. This paper introduces the fundamental principles, code framework, and typical applications of CorTAF-LBE, summarizes the team's previous research achievements, and provides an outlook for future work.