http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
3차원 오일러 방정식의 계산 효율성 증대를 위한 Adaptive Wavelet 기법의 적용
조동욱(D.U. Jo),박경현(K.H. Park),강형민(H.M. Kang),이도형(D.H. Lee) 한국전산유체공학회 2014 한국전산유체공학회지 Vol.19 No.2
The adaptive wavelet method is studied for the enhancement of computational efficiency of three-dimensional flows. For implementation of the method for three-dimensional Euler equation, wavelet decomposition process is introduced based on the previous two-dimensional adaptive wavelet method. The order of numerical accuracy of an original solver is preserved by applying modified thresholding value. In order to assess the efficiency of the proposed algorithm, the method is applied to the computation of flow field around ONERA-M6 wing in transonic regime with 4th and 6th order interpolating polynomial respectively. Through the application, it is confirmed that the three-dimensional adaptive wavelet method can reduce the computational time while conserving the numerical accuracy of an original solver.
추력과 효율 향상을 위한 AUV Double Hydrofoil의 모션 최적설계
소현규(H.K. So),조태현(T.H. Jo),이용한(Y.H. Lee),김진산(J.S. Kim),한준희(J.H. Han),구본찬(B.C. Koo),이도형(D.H. Lee) 한국전산유체공학회 2016 한국전산유체공학회지 Vol.21 No.1
While most AUV researches have concerned about single hydrofoil, practical AUV’s are generally operated with multiple hydrofoils. Double hydrofoil study attempts to evaluate thrust and efficiency with various flapping motions, and carries out design optimization using parametric analysis. Flow patterns such as vortex shedding and wake-body interaction are carefully investigated during design variable sensitivity analysis. The purpose of this design optimization is to find out the optimal motion that yields maximum thrust and efficiency. The design optimization employes several techniques such as table of orthogonal arrays, Kriging method, ANOVA analysis and MGA. Throughout this research, it is possible to find the optimal values of heaving ratio, heaving shift and pitch shift: Heaving ratio 0.950, heaving shift 23.120˚ and pitch shift 89.991˚ are found to be optimal values in double hydrofoil motions. Thrust and efficiency are 16.7% and 35.1% higher than existing AUV that did not consider nonlinear dependency of motion parameters. This results may offer an effective framework that is applicable to various AUV motion analyses and designs.