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At present, expert scoring is mainly used to evaluate the air combat control ability, which is not accurate enough to effectively achieve the desired effect. In order to evaluate air battle managers’ air combat control ability more scientifically and accurately, using eye-tracking technology, a quantitative evaluation model is established based on eye movement indicators. Specifically, the air combat control ability was comprehensively assessed using the GRA-TOPSIS method based on the EW-CRITIC combination weighting. The model innovatively uses eye movement indicators as a vital evaluation basis. Firstly, it puts forth a comprehensive evaluation method by combining GRA with TOPSIS methods, using the EW and CRITIC methods for combined weighting, and giving full play to the advantages of various evaluation methods. Secondly, it not only effectively copes with the problem that the traditional evaluation method is deeply affected by subjectivity but also creatively provides a reasonable means for future training evaluation of air battle managers. Finally, the effectiveness and feasibility of the evaluation model are verified through case analysis.

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The method of oscillating-foil energy extraction can be used to extract kinetic energy from the surrounding flow by a combined pitching and heaving motion of the foil. In order to improve the efficiency of energy extraction, a slotted foil with an active deflecting trailing-edge flap—inspired by the structure of the tail edge of bird wings—is designed. In this study, the unsteady Reynolds-averaged Navier–Stokes equation is solved to investigate the energy extraction performance of an oscillating foil at a Reynolds number of 5.0 × 105. In the numerical simulation, the dynamic overset mesh technology is used in order to ensure the accuracy and convergence of numerical solution. The effect of the deflecting motion of trailing-edge flaps on the efficiency of energy extraction is studied at a range of oscillating frequencies. In addition, the flow control mechanisms of slots on the oscillating foil are revealed by comparing the flow fields of the slotted foil and the NACA0015 foil. The result shows that active deflecting trailing-edge flaps can improve the efficiency of energy extraction over a wide range of oscillation frequencies. The active deflection of trailing-edge flaps increases the energy extraction efficiency of oscillating foils by 21.1% relative to conventional foils under a specific operating condition of oscillating frequency f* = 0.18. A detailed analysis of the flow fields indicates that the slot on the foil can suppress flow separation, while it has a negative effect on the attachment of leading-edge vortices. The deflecting trailing-edge flap enhances the heaving force. Therefore, the energy output and the efficiency of the oscillating foil are enhanced especially at the operating conditions of the oscillating foil without leading-edge vortex shedding.

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