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 : Liuyuan Zhao (검색결과 3 건)
- 무료
- 기관 내 무료
- 유료
-
Kuanjun Wang,Hongwei Li,Kanmin Shen,Zhigang Shan,Weida Ni,Liuyuan Zhao,Hongyu Wang 대한토목학회 2023 KSCE Journal of Civil Engineering Vol.27 No.6
The interaction between the pipeline and the surrounding soil is a critical factor in thebuckling analysis of the pipeline operating at high temperatures and pressures. The heatingpipeline alters the temperature and induces excess pore pressure in the surrounding soil,which in turn affects the mechanical properties of the soil. Therefore, a comprehensiveunderstanding of the thermo-mechanical response of the soil surrounding the pipeline duringoperation and shutdown is essential. To address this issue, this study developed a temperaturecontrolledpipe model test device that simulates the heating and cooling cycle of the pipe andthe temperature field and pore pressure response of the surrounding kaolin clay. The testresults showed that the soil temperature at the closest location to the pipe (0.1D) reached apeak value of approximately 48.7°C when the pipe was heated from 12.5°C to 55°C. Thepeak temperature decreased with increasing distance, reaching 22.5°C at 0.875D. Heattransfer analysis using ABAQUS software revealed that the influence range of the pipeline onthe soil temperature field during the heating cycle was about 2D. Additionally, a parametricstudy focused on the thermal conductivity (λsoil) of kaolin, and the best-fit value wasdetermined to be 0.6 W/(m·°C). The excess pore pressures were generated in the kaolinsurrounding the pipes during the heating cycle, and negative pore pressures were observedafter cooling cycle. Furthermore, a theoretical solution for calculating the thermally inducedpore pressure was derived, and preliminary verification showed good agreement between thetheoretically computed and experimentally measured results. These findings provide valuableinsights into the thermo-mechanical response of the soil surrounding pipelines duringoperation and shutdown, which can improve the design and safety of oil and gas pipelines.
-
Influences of Bridge Group on Thermal and Mechanical Properties of Epoxy Resins
Liu Yuan,Zhao Jun,Liu Ai-Qin,Liu Xiao-Qing,Luo Jun 한국고분자학회 2020 폴리머 Vol.44 No.4
In order to obtain thermosetting epoxy resin, it is the prerequisite condition that the epoxy precursor must contain at least two epoxy groups. Thus, bridge group is needed to link the epoxy groups, and naturally, the chemical structure of the bridge group may also influence the thermomechanical performances of the cured epoxy resin. However, literature about the effects of bridge group on properties of cured epoxy is seldom published. To fill the gap, three model epoxy monomers containing different bridge groups have been synthesized from 4,4"-dihydroxydiphenyl, 1,1-bis(4- hydroxyphenyl)cyclohexane and bisphenol A in this work. After chemical structure confirmation, all of the monomers are cured by methylhexahydrophthalic anhydride (HMMPA), and the properties of the obtained cured network are evaluated by differential scanning calorimetry (DSC), dynamic thermomechanical analysis (DMA), tensile test and scanning electron microscope (SEM). The results show that bulky bridge group can effectively increase the glass transition temperature, enhance the tensile strength, and enlarge elongation at break of the cured epoxy resin.
-
Liu Yuan,Yang Huiyuan,Zhao Yaoyao Fiona,Zheng Guolei 한국CDE학회 2022 Journal of computational design and engineering Vol.9 No.1
With the rapid advancement of the multimaterial additive manufacturing (AM) technology, the heterogeneous lattice structures (HLSs) comprising the multiphase materials with gradual variations have become feasible and accessible to the industry. However, the multimaterial AM capabilities have far outpaced the modeling capability of design systems to model and thus design novel HLSs. To further expand the design space for the utilization of AM technology, this paper proposes a method for modeling HLS with complex geometries and smooth material transitions. The geometric modeling and material modeling problems are formulated in a rigorous and computationally effective manner. The geometric complexity of HLS is significantly reduced by a semi-analytical unit cell decomposition strategy that is applied to split HLS into material units: struts and connectors. The smooth material transitions of the connector associated with multimaterial struts are realized by interpolating the discrete material property values defined at control points using a multiquadric radial basis function network.
연관 검색어 추천
이 검색어로 많이 본 자료
활용도 높은 자료
