http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
- 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
- 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
RISS 인기검색어
- 검색키워드
- 저자 : Zhigui Ren (검색결과 2 건)
- 무료
- 기관 내 무료
- 유료
-
Haoran Sun,Zhigui Ren,Junli Wang,Weifeng Wei,Yongyong Liang,Minghao Feng 대한기계학회 2021 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.35 No.6
The bucket shape of a hydraulic excavator influences its excavating performance and is determined by its shape line. In this study, the inner surface line projected on the symmetrical plane of the bucket was adopted as the bucket shape line, and the value ranges of the main parameters for the shape line were investigated. By considering the centre of the arc at the bucket bottom as the origin, the Cartesian coordinate system was established, and the integrated equation of the bucket line was derived based on the geometric constraints related to the shape line. A general optimisation model of the bucket line was established using the integrated equation. The effects of four design variables on the optimisation goal were determined using the bucket of a 21 T excavator as an example, and the optimal shape line of the bucket was obtained using a genetic algorithm. The results indicated that the cutting angle decreased by 9.92 % in comparison with that before optimisation, which was beneficial in decreasing the digging resistance. Additionally, the aspect ratio decreased by 5.75 %, thereby reducing the bucket weight. Thus, the integrated expression and the optimisation of shape lines provide a general method and theoretical basis for optimising the bucket shape.
-
Junli Wang,Jinyang Li,Shuai Lei,Zhigui Ren,Yayin He 한국항공우주학회 2022 International Journal of Aeronautical and Space Sc Vol.23 No.2
To explore the geometric nonlinearity of high-aspect-ratio wing due to large deformation, the aerodynamics were solved by Navier–Stokes governing equation based on the loose coupling method of CFD/CSD. Considering the large displacement stiffness matrix of wing structure, the Newton–Raphson method is used to solve the nonlinear elastic deformation of the structure. A geometrically nonlinear static aeroelastic coupling calculation program is developed. During the coupling process, an improved elastic approximation method was used to update the aerodynamic mesh, and the data exchange on the coupling interface was realized by a fixed-volume interpolation method. The reliability of the proposed method was verified by HIRENASD wing model. Finally, the effects of geometric nonlinear static aeroelasticity on longitudinal aerodynamic characteristics and stability of swept wing with high aspect ratio at different angles of attack are studied using this method. The results show that the lift direction of a high-aspect-ratio wing is significantly deformed under the influence of aerodynamic loads. The effective angle of attack of the wing decreases with the whole deformation, and the degree of decrease increases from the root to the tip. The significant flexural and torsional deformation will change the lift coefficient and drag coefficient of the wing and reduce the margin of the static stability of the wing.
연관 검색어 추천
이 검색어로 많이 본 자료
활용도 높은 자료
