발전용 저압터빈 최종단 블레이드의 정적 유체-구조 연계해석

Abstract

Key Words: Fluid-Structure Coupled Analysis(유체-구조연계해석), Low-Pressure Turbine(저압터빈), SweptbackWing(후퇴익), NASA Rotor 37초록: 본논문에서는, 운전조건에서의저압최종단블레이드에대하여약결합유체-구조연계해석기법을이용한해석이수행되었다. 저압터빈최종단에대한해석이전에경계조건에대한검증을위하여15도후퇴익과NASARotor 37을대상으로예비해석이수행되었다. 각각의해석결과들을기존문헌들과비교하였다. 15도후퇴익에대한안정상태와불안정상태에서동적FSI해석이수행되었다. 해석결과변위가일정한안정상태에비하여고속에서는0.05 초만에발산하는결과를산출하였다. NASA Rotor 37의정상상태해석결과를바탕으로정적·동적FSI해석을수행하여뒷전의변형크기에대하여정적FSI 결과와동적FSI간의차이가있음을확인하였다. 저압최종단블레이드의형상측정및동특성시험을바탕으로해석모델을생성하였다. 이를바탕으로, 운전조건에서저압최종단블레이드에대한정적유체-구조연계해석을성공적으로수행하였다.Abstract: In this study, a loosely coupled fluid-structure interaction (FSI) analysis was conducted for a low-pressure(LP) final-stage rotor blade. Preliminary FSI analyses of a 15° sweptback wing and a NASA Rotor 37 compressorblade were performed for verifying the boundary conditions. The results were compared with the established literaturesfor each model. The FSI analysis of the 15° sweptback wing was carried out under both stable and unstableconditions. The excessive deformation of the wing was observed within 0.05 s under the unstable condition which ishigher than the divergence speed of a wing compared with the stable condition. On the basis of the results of asteady-state study, an unsteady state FSI analysis was conducted for a NASA Rotor 37. Different deformations wereobserved at trailing edge of the blade in the static FSI and dynamic FSI analysis. A 3D FE model of a LP rotor wasgenerated from the span-wise section data. In order to develop a reasonable model, an impact test was performed andcompared to the FE model. Using this FE model, the steady-state FSI analysis was performed successfully.