由于气动加热、热沉紧缺等问题，民用超声速运输机的环控系统和热管理系统面临着严峻的挑战。而目前对于民用运输机环控系统的研究主要针对亚声速民机，对超声速民机关注不足，亟需针对超声速民机环控系统展开深入研究。综合考虑超声速飞行时可用热沉特性，提出了一种集成在燃油热管理系统中、具有热沉模式切换功能的新型环控系统，并对环控系统和燃油热管理系统进行热力学建模仿真。在典型飞行任务剖面下进行仿真分析，该系统可以满足超声速巡航、减速下降阶段客舱供气温度不大于18℃、燃油温度不大于150℃等关键热安全边界条件。巡航阶段设计航时增长或燃油初始温度升高时，仅使用燃油热沉可能导致系统热航时小于设计航时，此时切换模式引入冲压空气热沉可使系统热航时增加。减速下降阶段需同时使用燃油和冲压空气热沉，此时热航时受到燃油温度限制和供气温度限制的共同约束，调控循环燃油流量和冲压空气流量可延长热航时。双热沉模式切换策略平衡了热安全性与经济性，为超声速民机综合热管理系统设计提供了理论支撑与工程优化路径。

Aerodynamic heating and heat sink scarcity pose critical challenges for the environmental control system (ECS) and thermal management systems of civil supersonic transports. Current research on ECS primarily focuses on subsonic aircraft, with insufficient attention to supersonic configurations, necessitating dedicated investigations into supersonic civil aircraft ECS. Considering the available heat sinks on the aircraft during supersonic flight, this study proposes a ECS integrated into the fuel thermal management system with heat sink mode switching function. Thermodynamic modeling and simulation were con-ducted for the systems. Simulation analysis under typical flight mission profiles demonstrated that this integrated system sat-isfies critical thermal safety boundary conditions, including maintaining cabin supply air temperature below 18°C and fuel temperature under 150°C during supersonic cruise and deceleration descent phases. The research reveals that when the de-sign endurance increases during cruise phase or initial fuel temperature rises, relying solely on fuel heat sinks may result in system thermal endurance falling below design requirements. Switching to ram air heat sink mode in such scenarios can ex-tend thermal endurance. During deceleration descent, simultaneous utilization of both fuel and ram air heat sinks becomes necessary, where thermal endurance becomes co-constrained by fuel temperature limits and supply air temperature require-ments. Regulating the recirculating fuel flow rate and ram air flow rate proves effective in prolonging thermal endurance under these dual constraints. The dual-heat sink mode switching strategy balances thermal safety and economy, providing theoretical support and engineering optimization pathways for the design of integrated thermal management systems in supersonic civil aircraft.