Future fuel cell driven aircraft configurations can be one way to achieve a significant reduction of emissions and contribute to the sustainability of aviation systems to meet the climate targets set by the European Union. However, even modern fuel cells still generate a lush amount of waste heat while producing the needed electricity for the propulsion system. Conventional aircraft cooling takes place in heat exchangers that are exposed to the outer flow field and thus increase the overall drag of the aircraft. To avoid additional drag, the Cluster of Excellence SE²A – subproject B4.1 develops thin-walled skin heat exchangers that are capable of dissipating the fuel cell waste heat while maintaining or even decreasing the aircrafts overall drag. The feasibility of such heat exchangers is numerically investigated. The three fields (outer aerodynamic flow, heat exchanger structure and the one-phase cooling channel flow) are discretized (FVM, FEM) and coupled using a partitioned approach based on different combinations of Dirichlet, Neumann and Robin boundary conditions. Due to their different time scales, the structure is simulated transiently while the fluid domains can be considered stationary as already shown for cooling channel structures in [1, 2]. Due to the low structural heat capacity the design cases are mainly quasi-steady states. The simulation approach stops as soon as the structure’s temperature field reaches its stationary state. The goal of the study presented is to determine the most computational efficient coupling method while providing sufficient simulation stability and to evaluate the influence of simulation parameters such as the coupling time step size and the used relaxation scheme for the partitioned approach. This knowledge will be used in following computationally very expensive simulations of complex configurations to save time and thus computing power.