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Lip and diffuser are two important parts of S-shaped inlet, which are difficult to balance in the optimization design of S-shaped inlet. This paper presents an optimization method for S-shaped inlet. Firstly, the parametric models of the lip and the diffuser are established. Combining with automatic mesh generation technology, numerical simulation and genetic algorithm, an optimization platform of s-shaped inlet design based on Isight is established. Aiming at the design of inlet for an unmanned aerial vehicle (UAV), compared with the prototype, the total pressure recovery coefficient of the optimized inlet obtained by this optimization method is increased by 1.5%, and the steady-state circumferential distortion is reduced by 58.6%. The wind tunnel experiment is carried out to obtain the aerodynamic performance of the inlet, and the experimental results are in good agreement with the numerical simulation results.

An adaptive mesh refinement (AMR) technique based on nodal linked-list data structure for lattice Boltzmann method (LBM) is proposed in this paper. It makes connections between nodal linked-list data structure which is hierarchical and LBM calculation to retain the simplicity of LBM. Based on uniform meshes, the adaptive algorithm refines the meshes by constructing the linked-list of nodes and levels for mesh levels refined. In the nodal linked-list data structure, the relationships for nodal neighbors and upper and lower level indexes of nodes are appointed to help implement the LBM process in the different mesh levels. To guarantee precise transmission of flow field information and numerical stability in the different mesh levels, the average interpolation for temporal and spatial space is used, which chimes in with the accuracy of LBM itself. To verify the present method, flows over square cylinder at Re=30 and circle cylinder at Re=200 are carried out.