Turbulence kinetic energies in confined vortex flows have been studied. The studies were based on the experiments performed in a vortex chamber. In the experiments, a Laser Doppler Anemometry (LDA) was used to perform...Turbulence kinetic energies in confined vortex flows have been studied. The studies were based on the experiments performed in a vortex chamber. In the experiments, a Laser Doppler Anemometry (LDA) was used to perform flow measurements inside the vortex chamber, which provided the data for the kinetic energy analysis. The studies concentrated on the influences of the contraction ratio and the inlet air flow rate on the kinetic energy, and analyzed the characteristics of the kinetic energy in the confined vortex flows, including the distributions of the tangential component, radial component and total turbulence kinetic energy. In the paper, both the experimental techniques and the experimental results were presented. Based on a similarity analysis and the experimental data, an empirical scaling formula was proposed so that the tangential component of the turbulence kinetic energy was dependent only on the parameter of the contraction ratio.展开更多
To investigate the nature of the Ψ（3770） resonance and to measure the cross section for e^＋e^-→DD, a cross-section scan data sample, distributed among 41 center-of-mass energy points from 3.73 to 3.89 GeV, was ta...To investigate the nature of the Ψ（3770） resonance and to measure the cross section for e^＋e^-→DD, a cross-section scan data sample, distributed among 41 center-of-mass energy points from 3.73 to 3.89 GeV, was taken with the BESIII detector operated at the BEPCII collider in the year 2010. By analyzing the large angle Bhabha scattering events, we measure the integrated luminosity of the data sample at each center-of-mass energy point. The total integrated luminosity of the data sample is 76.16±0.04±0.61 pb^-1, where the first uncertainty is statistical and the second systematic.展开更多
文摘Turbulence kinetic energies in confined vortex flows have been studied. The studies were based on the experiments performed in a vortex chamber. In the experiments, a Laser Doppler Anemometry (LDA) was used to perform flow measurements inside the vortex chamber, which provided the data for the kinetic energy analysis. The studies concentrated on the influences of the contraction ratio and the inlet air flow rate on the kinetic energy, and analyzed the characteristics of the kinetic energy in the confined vortex flows, including the distributions of the tangential component, radial component and total turbulence kinetic energy. In the paper, both the experimental techniques and the experimental results were presented. Based on a similarity analysis and the experimental data, an empirical scaling formula was proposed so that the tangential component of the turbulence kinetic energy was dependent only on the parameter of the contraction ratio.
基金Supported by National Key Basic Research Program of China(2015CB856700)National Natural Science Foundation of China(NSFC)(11235011,11335008,11425524,11625523,11635010)+13 种基金the Chinese Academy of Sciences(CAS)Large-Scale Scientific Facility Programthe CAS Center for Excellence in Particle Physics(CCEPP)Joint Large-Scale Scientific Facility Funds of the NSFCCAS(U1332201,U1532257,U1532258)CAS Key Research Program of Frontier Sciences(QYZDJ-SSW-SLH003,QYZDJ-SSW-SLH040)100 Talents Program of CASNational 1000 Talents Program of China,INPACShanghai Key Laboratory for Particle Physics and Cosmology,German Research Foundation DFG under Contracts Nos.Collaborative Research Center CRC 1044,FOR 2359Istituto Nazionale di Fisica Nucleare,Italy,Koninklijke Nederlandse Akademie van Wetenschappen(KNAW)(530-4CDP03)Ministry of Development of Turkey(DPT2006K-120470)National Science and Technology fundThe Swedish Research Council,U.S.Department of Energy(DEFG02-05ER41374,DE-SC-0010118,DE-SC-0010504,DE-SC-0012069)University of Groningen(RuG)and the Helmholtzzentrum fuer Schwerionenforschung GmbH(GSI)Darmstadt,WCU Program of National Research Foundation of Korea(R32-2008-000-10155-0)
文摘To investigate the nature of the Ψ（3770） resonance and to measure the cross section for e^＋e^-→DD, a cross-section scan data sample, distributed among 41 center-of-mass energy points from 3.73 to 3.89 GeV, was taken with the BESIII detector operated at the BEPCII collider in the year 2010. By analyzing the large angle Bhabha scattering events, we measure the integrated luminosity of the data sample at each center-of-mass energy point. The total integrated luminosity of the data sample is 76.16±0.04±0.61 pb^-1, where the first uncertainty is statistical and the second systematic.
