Abstract: The skin heat exchanger cleverly utilizes the vast external atmosphere as an immense heat sink, and efficiently dissipating the heat generated by the electronic devices housed within an aircraft. This heat dissipation process occurs primarily through convective heat transfer, a method that not only significantly reduces the aircraft's energy consumption but also helps to minimize its overall weight. By adopting this approach, the skin heat exchanger stands as a testament to a highly innovative, low-energy, and passive heat transfer technique that does not require active intervention or external power sources. To delve deeper into its potential applications within a specific aircraft, a meticulous process was carried out. A precise flow field calculation model was first established, with advanced 3D modeling techniques and mesh partitioning being leveraged to capture every intricate detail of the aircraft's external surface. Being armed with the commercial CFD （Computational Fluid Dynamics) software ANSYS Fluent, a numerical simulation of the aircraft's external flow field characteristics was conducted. The convective heat transfer coefficient for the aircraft's outer wall, a crucial parameter for understanding and predicting heat transfer efficiencies, was accurately obtained by this simulation. With this invaluable coefficient in hand, a structural model of the skin heat exchanger was then developed. Its heat transfer performance was meticulously evaluated and analyzed, with the obtained convective heat transfer coefficient being used as the thermal boundary condition. It was ensured by this approach that the model was grounded in reality, reflecting the actual heat transfer dynamics that would occur in a real-world application. Through this rigorous and detailed analysis, a comprehensive understanding of the skin heat exchanger's performance and potential benefits within the aircraft could be gained.