A modified nonlinear sub-grid scale model for large eddy simulation with application to rotating turbulent channel flows Phys. Fluids 24, 075113 (2012) Scaling range of velocity and passive scalar spectra in grid turbulence Phys. Fluids 24, 075101 (2012) On Lagrangian single-particle statistics Phys. Fluids 24, 055102 (2012) The length distribution of streamline segments in homogeneous isotropic decaying turbulence Phys. Fluids 24, 045104 (2012) Conditional vorticity budget of coherent and incoherent flow contributions in fully developed homogeneous isotropic turbulence Phys. Fluids 24, 035108 (2012) Additional information on Phys. Fluids

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The high-resolution direct numerical simulations (DNSs) of incompressible turbulence with numbers of grid points up to 4096 3 have been executed on the Earth Simulator (ES). The DNSs are based on the Fourier spectral method, so that the equation for mass conservation is accurately solved. In DNS based on the spectral method, most of the computation time is consumed in calculating the three-dimensional (3D) FastFourier Transform (FFT), which requires huge-scale global data transfer and has been the major stumbling block that has prevented truly high-performance computing. By implementing new methods to efficiently perform the 3D-FFT on the ES, we have achieved DNS at 16.4 Tflops on 2048 3 grid points. The DNS yields an energy spectrum exhibiting a wide inertial subrange, in contrast to previous DNSs with lower resolutions, and therefore provides valuable data for the study of the universal features of turbulence at large Reynolds number. *

The statistics of energy transfer is studied by using the data of a series of high-resolution direct numerical simulations of incompressible homogeneous turbulence in a periodic box with the Taylor micro-scale Reynolds number R and grid points up to approximately 1130 and 4096 3 , respectively. The data show that the energy transfer T across the wave number k is highly intermittent and the skewness S and flatness F of T increase with k approximately as S / ðkLÞ S , F / ðkLÞ F in the inertial subrange, where S $ 2=3, F $ 1 and L the characteristic length scale of energy containing eddies. The comparison between the statistics of T, the energy dissipation rate and its average r over a domain of scale r shows that T is less intermittent than , while there is a certain similarity between the probability distribution functions of T and r .

This paper deals with merging control of vehicles with inter-vehicle communication on highways, which would greatly contribute to increase safety and decrease traffic congestion. Algorithms for merging control of vehicles using a concept of a virtual vehicle and for inter-vehicle communication for the control are presented. A virtual vehicle is generated b y mapping a vehicle on a lane onto another lane, in order to enable longitudinal control between a vehicle on a main lane and one on a sub lane to make smooth merging. The inter-vehicle communication is essential in the merging control algorithm, because the generation of the virtual vehicle requires the inter-vehicle communication. The data transmission algorithm in the communication consists of an intra-platoon algorithm and an inter-platoon one. The former is featured by provision of the interruption detective gaps that allow to reduce transmission delay caused by collision, and the latter is featured by data transmission only between lead vehicles. The simulation resultsshow the efficiency of the data transmission and the feasibility of merging control using the data transmission algorithm. When a platoon consists of ten vehicles, the transmission rate is tree times as eficient as the conventional algorithm and it is suficient for the merging control.