The genus Episymploce Bey-Bienko,1950 from China is reviewed.Eight new species are illustrated.The habitus and male genitalia of these new species are described.
This paper aims to tackle the calculation efficiency problem raised in the cavitation-flow simulation of the aviation centrifugal pump due to the fading-away interface resulting from the dissipation of numerics used i...This paper aims to tackle the calculation efficiency problem raised in the cavitation-flow simulation of the aviation centrifugal pump due to the fading-away interface resulting from the dissipation of numerics used in the phase-change control equation for unstructured-grid multiphase flow,and due to the limitation of flow time-step in whole flow regimes,the control equation of vapor–liquid two-phase flow considering cavitation mass transport is established firstly,modifying the momentum equation by introducing the surface tension,and adding the artificial convective flow to the phase equation to solve the numerical dissipation problem.Secondly,in consideration of the local time step principle and based on the multi-dimensional general limiter algorithm with explicit solutions under the OpenFOAM platform,a solution method of steady-state VOF (Volume of Fluid) model considering cavitation two-phase change is constructed,and the feasibility of this method is verified by NACA hydrofoil and NASA flat plate inducer.Finally,based on the platform developed,the cavitation performance of an aviation centrifugal pump inducer is analyzed.The research results show that the error of the calculated cavitation pressure distribution for NACA hydrofoil between the simulation test and the experimental-test is less than 5%,and the maximum error of calculated cavitation number at pump head dropping for NASA high-speed flat plate inducer between the simulation test and the experimental-test is 2.1%.The cavitation area observed in the simulation test is the same as that obtained in the high-speed photography test.Based on the OpenFOAM simulation method,the position of pump head dropping of the fuel centrifugal pump can be accurately captured.The error of the calculated cavitation number at pump head dropping between the simulation test and the experimental test is about 3.7%,showing high calculation accuracy.展开更多
A new species, Hemithyrsocera hemiptera sp. nov., is described from Southwest China, based on its shortened tegmina, and the lack of hind wings, including the illustrations of its habitus and male genitalia. A key to ...A new species, Hemithyrsocera hemiptera sp. nov., is described from Southwest China, based on its shortened tegmina, and the lack of hind wings, including the illustrations of its habitus and male genitalia. A key to the Chinese species of the genus is provided. The type material is deposited in Shanghai Entomological Museum(SEM), Chinese Academy of Sciences(CAS).展开更多
The book, Cockroaches of Southeastern China, wrote by Xianwei Liu, Weibing Zhu, Li Dai and Hanqiang Wang, was published in 2017.In this book,the cockroachs fauna of the Southern China was observed,occupied Shandong, A...The book, Cockroaches of Southeastern China, wrote by Xianwei Liu, Weibing Zhu, Li Dai and Hanqiang Wang, was published in 2017.In this book,the cockroachs fauna of the Southern China was observed,occupied Shandong, Anhui,Jiangsu, Shanghai, Zhejiang, Fujian, Jiangxi, Taiwan, Guangdong and Hainan Provinces.展开更多
基金sponsored by the Science-Technology Basic Condition Platform from the Ministry of Science and Technology of People’s Republic of China(2005DKA21402)
文摘The genus Episymploce Bey-Bienko,1950 from China is reviewed.Eight new species are illustrated.The habitus and male genitalia of these new species are described.
基金supported by the National Science and Technology Major Project, China (No. J2019-V-0016-0111)the Aviation Engine and Gas Turbine Basic Science Center Project, China (No. P2022-B-V-003-001)+3 种基金the Defense Industrial Technology Development Program, China (No. JCKY2022607C002)the AECC Industry University Cooperation Project, China (No. HFZL2022CXY013)the National Natural Science Foundation of China (No. 52372396)the Key R&D Project in Shaanxi Province, China (No. 2021GXLH-01-16)。
文摘This paper aims to tackle the calculation efficiency problem raised in the cavitation-flow simulation of the aviation centrifugal pump due to the fading-away interface resulting from the dissipation of numerics used in the phase-change control equation for unstructured-grid multiphase flow,and due to the limitation of flow time-step in whole flow regimes,the control equation of vapor–liquid two-phase flow considering cavitation mass transport is established firstly,modifying the momentum equation by introducing the surface tension,and adding the artificial convective flow to the phase equation to solve the numerical dissipation problem.Secondly,in consideration of the local time step principle and based on the multi-dimensional general limiter algorithm with explicit solutions under the OpenFOAM platform,a solution method of steady-state VOF (Volume of Fluid) model considering cavitation two-phase change is constructed,and the feasibility of this method is verified by NACA hydrofoil and NASA flat plate inducer.Finally,based on the platform developed,the cavitation performance of an aviation centrifugal pump inducer is analyzed.The research results show that the error of the calculated cavitation pressure distribution for NACA hydrofoil between the simulation test and the experimental-test is less than 5%,and the maximum error of calculated cavitation number at pump head dropping for NASA high-speed flat plate inducer between the simulation test and the experimental-test is 2.1%.The cavitation area observed in the simulation test is the same as that obtained in the high-speed photography test.Based on the OpenFOAM simulation method,the position of pump head dropping of the fuel centrifugal pump can be accurately captured.The error of the calculated cavitation number at pump head dropping between the simulation test and the experimental test is about 3.7%,showing high calculation accuracy.
基金sponsored by the Science-technology basic condition platform from The Ministry of Science and Technology of People’s Republic of China(2005DKA21402)
文摘A new species, Hemithyrsocera hemiptera sp. nov., is described from Southwest China, based on its shortened tegmina, and the lack of hind wings, including the illustrations of its habitus and male genitalia. A key to the Chinese species of the genus is provided. The type material is deposited in Shanghai Entomological Museum(SEM), Chinese Academy of Sciences(CAS).
文摘The book, Cockroaches of Southeastern China, wrote by Xianwei Liu, Weibing Zhu, Li Dai and Hanqiang Wang, was published in 2017.In this book,the cockroachs fauna of the Southern China was observed,occupied Shandong, Anhui,Jiangsu, Shanghai, Zhejiang, Fujian, Jiangxi, Taiwan, Guangdong and Hainan Provinces.
