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In this paper, an entropy analysis and design optimization methodology is combined with multi-objective airfoil shape optimization to demonstrate the impact of entropy generation on aerodynamic designs. Model equations for the calculation of the local entropy generation rate in turbulent flows are presented by extending the Reynolds-averaging procedure to the entropy balance equation. We use the CST parametric method to model the airfoil configuration and combine the CFD solver with multi-objective optimization algorithm respectively, to compute aerodynamics quantities such as lift-drag ratio and entropy generation rate. We obtain the optimized airfoils that maximize lift-drag ratios and minimize entropy generation rates as optimization objectives. Moreover, the present method is compared with the traditional method. From the multi-objective solutions, a designer can select a set of airfoil shapes with low relative entropy generation, small actuation cost, and improved aerodynamic performance at the design conditions. The optimized results unfold that, the proposed method is capable of realizing better performance in practical aerodynamic optimization, with the features of strong global convergence and improved aerodynamic performance in the increase of lift-drag ratio and the decrease of entropy generation rate, compared with the initial population. [ABSTRACT FROM AUTHOR]

Aero-train is a new transportation with high speed and low energy consumption is based on the wing-in-ground effect(WIG). The Aero-train concept proposed Tohoku University in Japan in the first place and the relevant research carried out the support of the Japanese government. In this paper, the aerodynamic optimization design of LA203A is carried out by using genetic algorithm and numerical simulation method, the simulation analysis ground effect optimized airfoil, the influence of the ground clearance and the attack angle on the drag, lift and lift drag ratio of the -train and the aerodynamic characteristic is improved . CFD technology to the aerodynamic characteristic of AERO-1 with wings and optimized wings and the flow field characteristics around the front and rear wing, the aerodynamic characteristics of Aero-train with optimized wing, the wind tunnel test was in Jilin University. The lift-drag ratio of optimized airfoil which optimized by genetic algorithm method is 26% higher than the airfoil. The provides theoretical basis for the analysis of wing-in-ground effect and the research Aero-train. [ABSTRACT FROM AUTHOR]

This paper proposes that an elite selection is applied to the parent population before it is directly added into the combined population, as is done in the original NSGA-II method. This modification can better avoid the algorithm's premature convergence to local optimums, and better globally explore the sample space. An analytical test problem with many local optimums is solved using the improved method. The result is compared with those of several other optimization methods. The improvements of the proposed modification are confirmed. Then the improved NSGA-II method is used to find the optimum element positions and deflection angles of the landing configuration of a multi-element airfoil, to maximize the lift coefficient. The optimal result is close to that from the original NSGA-II, while the optimum is achieved with fewer iterations. This satisfactory result shows that the improved optimization method is feasible and efficient for practical use. [ABSTRACT FROM AUTHOR]

The work in this paper is based on the optimization software, using the exactly optimization technique. The hypersonic aerodynamic performance is calculated by numerically solving the Euler equations and the maximum surface heat flux is calculated by solving the Fay-Riddell equation. To test our method, the CTV is optimized. The Spaceship reentry capsule has been optimized as a particular instance. This research work can be as the groundwork for the reentry capsule optimization. [ABSTRACT FROM AUTHOR]

An optimization design model for blades of horizontal axis wind turbines has been presented in this paper, which takes the maximum of annual energy output as the design objective. And the probability of wind speed distribution has been taken into account. The PROPID program is used to get the baseline of blade with a better performance firstly, and then the genetic algorithm is used to optimize the baseline. In order to get a smooth blade figuration, a 5th order Bezier curve is used to fit through the control points. Using the developed optimization method, the blades of a 600kW wind turbine were designed. Compared with the initial blades, the designed shows obvious advantages, which verifies the effectiveness of the optimization method. [ABSTRACT FROM AUTHOR]