http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Le Qi,Jianxing Zhou,Pengcheng Jin,Mingming Wang,Yongzheng Su,Hengyu Zhou,Guochun Liu,Lirui Song 대한기계학회 2023 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.37 No.9
In this paper, a rib layout optimization method that can efficiently reduce the radiated noise of gearboxes is proposed. Taking the secondary gearbox as the research object, the radiated noise of the housing is calculated using the FEM/BEM method, the process of determining the region with the maximum acoustic contribution is illustrated, and a topology optimization model that can reduce the air noise on the field points of the gearbox is established with the surface normal velocity of the region as the optimization target. The method is applied to add new noise reduction ribs on the surface of the gearbox. The results show that after combining the topology optimization with the acoustic contribution analysis, the sound pressure in the area with the highest sound pressure on the gearbox sound field is significantly reduced by adding new noise reduction ribs according to the optimization results.
Le Qi,Quanwei Cui,Cheng Wang,Xueyan Sun,Janxing Zhou,Pengcheng Jin,Guochun Liu,Lirui Song 대한기계학회 2023 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.37 No.12
In this paper, a simplified acoustic optimization method is proposed to replace the sound power with the maximum normal velocity of the surface as a direct target, a topological optimization model of the variable density method is established to reduce the acoustic radiation of the structure, and the relationship between the form of damping distribution and the acoustic radiation is investigated. The complex modulus model is used to describe the viscoelastic material intrinsic relationship of the damping layer. The effects of different excitation frequencies on the topology optimization results are discussed. The radiated noise is simulated using the finite element method and the boundary element method. Five plates are fabricated according to the damping layer layout for different single-frequency excitations. Modal and acoustic experiments are carried out to validate the proposed method. The numerical and experimental results show that there is a significant reduction in the sound pressure level (SPL).
Jiangbo He,Hua-Jie Zhu,Gui-Fen Luo,Guang-Ming Liu,Yan Li,Hao Chen,Shaopeng Chen,Xin Lu,Guochun Zhou,Yong-Xian Cheng 대한화학회 2010 Bulletin of the Korean Chemical Society Vol.31 No.8
The whole plant of Euphorbia helioscopia is an important traditional Chinese medicine. Fom its BuOH soluble extract,one new lactam (1), three new terpenoids (2-4) including a new naturally occurring compound, and three known compounds were isolated. Their structures were identified by spectroscopic evidences. In particular, the absolute configurations of side chain of compounds 1 and 2 were determined using computational methods.
He, Jiang-Bo,Zhu, Hua-Jie,Luo, Gui-Fen,Liu, Guang-Ming,Chen, Hao,Li, Yan,Chen, Shaopeng,Lu, Xin,Zhou, Guochun,Cheng, Yong-Xian Korean Chemical Society 2010 Bulletin of the Korean Chemical Society Vol.31 No.8
The whole plant of Euphorbia helioscopia is an important traditional Chinese medicine. Fom its BuOH soluble extract, one new lactam (1), three new terpenoids (2-4) including a new naturally occurring compound, and three known compounds were isolated. Their structures were identified by spectroscopic evidences. In particular, the absolute configurations of side chain of compounds 1 and 2 were determined using computational methods.