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The present article describes the combination of the correlation based transition model of Menter et al. with the Detached Eddy Simulation (DES) and Delayed Detached Eddy Simulation (DDES) methodology. The interaction between transition model and DES or DDES method was investigated by T3A test case. The grid sensitivity of the combined methodology is discussed and the resolution is given. Then, the simulation of flow over foil of medium thick at stall angle was performed. The combined methodology produce results that have better agreement with experiment comparing to RANS transition model or fully turbulent DES/DDES alone. And the DDES based combined model shows a better agreement with experiment in the simulation of trailing edge separation comparing to DES based combined model.

Applying common surrogate models to problems have numerous output variables is computational expensive, since the number of surrogate models should be constructed equals to the number of output variables. This paper presents an efficient strategy to solve this problem. For that, snapshot Proper Orthogonal Decomposition (POD) is used to extract a few main basis modes from certain number of samples. The predicted result of a large-scale output problem comes from the linear superposition of these basis modes. Common surrogate models just need to predict the coefficients for these basis modes. Through this strategy, The Mach numbers at 36864 points around an airfoil are predicted by just constructing 12 kriging surrogate models. The predicted Mach number distributions fit with the CFD results very well, that proves the efficiency of this strategy.

The aerodynamic shape optimization design system was established in this paper. In the system, the RANS equation was used for solving the flowing; the free form deformation (FFD) method was used for the geometry parameterization, and the genetic algorithm was used for the optimization search. For the reducing of the time cost, the Kriging model was used for the surrogate model instead of the CFD simulation during the optimization design. The aerodynamic shape design of a swept wing was presented which used the system, and the result indicated that the 14% drag coefficient was reduced at the cruise conditions, which proved the validity of the system.

In this paper, a multi-objective optimal planning design model including net cost, loss of capacity and pollutant emission in a life cycle was presented for a stand-alone microgrid system with diesel generators, wind turbine generators, photovoltaic generation and lead-acid battery. In this model, the two coordinated operational strategies between diesel generators and battery, the dispatching method for diesel generators, and the reserve capacity were considered. The type and capacity of distributed generation units were selected as the optimal variables. The optimal allocation of distributed generation units and battery for an island microgrid system was carried out under the different combination objectives and control strategies by the self-developed software (Planning Design System for Microgrid, PDMG).

This paper studied the suspension characteristics of ginkgo, and designed a cleaning machine of ginkgo as well. At the same time, the effects of feeding speed, the wind speed and the angle of wind outlet on the performance of the equipment were analyzed, and a mathematical model was established. By taking multi-objective optimization method and response surface method, this paper obtained the conclusion that the best combination conditions of cleaning equipment of ginkgo: the feeding speed was 270.86kg/h, the wind speed was 9.25m/s, and the angle of wind outlet was 17°. Then the cleaning equipment reached the best performance: the loss rate was 1.20%, while the cleaning rate was 95.21%.