The purpose of this study was to investigate the flow characteristics and cooling performance for the heavy turbine blade with different shapes. Research was focused on the numerical study on forced convective heat transfer coefficients for three different blades with base, tip, and hole. Thus, selected local locations for various temperature distributions were shown in the flow domain. Final temperature on the local surface of blades was compared with three different blades. According to the results of velocity and temperature distributions in the fluid domain, the blade with holes had the best convective cooling performance with higher 13-16% average heat transfer coefficient than the other two blades. Apparent vortex at the tip of tip and hole blade caused the stable temperature drop. According to the calculations of local convective heat transfer coefficient between blade surface and atmosphere in the blade, approximately 18% of heat transfer coefficient at hole was higher than the base blade and 7% at hole blade was higher than the base blade. Lowest cooling performance existed at the center position of all three blades.

In this research, the design optimization of a composite sandwich has been performed for using as an airplane wing skin. Automated analysis framework for aero-structure interaction is used for calculating load data on the wing. For automated analysis framework, FLUENT is used for computational fluid dynamics (CFD) analysis. CFD mesh is generated automatically by using parametric modeling of CATIA and GAMBIT. A computational structure mechanics (CSM) mesh is generated automatically by the parametric method of the CATIA and visual basic script of NASTRAN-FX. The structure is analyzed by ABAQUS. Composite sandwich optimization is performed by NASTRAN SOL200. Design variables are thicknesses of the sandwich core and composite skin panel plies. The objective is to minimize the weight of the wing and constraints are applied for wing tip displacement, global failure index and local failure indexes.

A fully coupled thermo-mechanical model is adopted to study the temperature distribution and the material deformation in friction stir welding(FSW) process. Rotational speed is most important parameters in this research. Three dimension results under different process parameters were presented. Result indicate that the maximum temperature is lower than the melting point of the welding material. The higher temperature gradient occurs in the leading side of the workpiece. The maximum temperature can be increased with increasing the tool angular velocity, rpm in the current numerical modeling. In this research ABAQUS Ver.6.7 is to analyze a fully coupled thermo-mechanical model. ALE(Arbitrary Lagrangian-Eulerian) finite element formulation is used for the large deformation in FSW process and using the Mass scaling for the analysis time efficiency.

In this paper, design optimization of C-frame of a precision drilling and autorivet machine has been performed. The machine, Autoriveter has been developed by Korea Aerospace Industry (KAI), For current autoriveter, it is hard to achieve high efficiency because of heavy weight of the machine. In this paper, we suggest new structure of the current C-frame, a part of autoriveter, by optimization. The result of the study can give much profit for mass-production of the machine.