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In this paper, a Reynolds number increase transition from self-oscillations close to single-frequency ones to the temporally chaotic regime in the flow in a cylindrical channel driven by a spatially periodic force with four half-periods is experimentally investigated. The parameter ε proportional to the mean rate of the kinetic energy dissipation in unit mass per unit time associated with perturbations in the fluid is used as a basic characteristic of self-oscillations. The Reynolds number dependence ε(Re) for single frequency self-oscillations is considered theoretically. [ABSTRACT FROM AUTHOR]

The advent of user-friendly in-flight process diagnostic tools has significantly improved our understanding of thermal spray processes. This paper examines the critical attributes of these diagnostic measurements and the applicability of the nondimensional group parameters as a mapping strategy for data visualization. Specifically, first-order process maps (process-particle interactions) have been addressed by converting the temperature ( T)-velocity ( V) of particles obtained via diagnostics into nondimensional group parameters [Melting Index (MI)-Reynolds number (Re)]. This approach provides an improved description of the thermal and kinetic energy of particles and allows for cross comparison of diagnostic data within a given process for different materials, comparison of a single material across different thermal spray processes, and detailed assessment of the melting behavior through recourse to analysis of the distributions. An additional group parameter, Oxidation Index (OI), has been applied to relatively track the oxidation extent of metallic particles under different operating conditions. [ABSTRACT FROM AUTHOR]

Abstract.: In present paper we recall the canonical Taylor-Green vortex problem solved by in-house implementation of the novel CABARET numerical scheme in weakly compressible formulation. The simulations were carried out on the sequence of refined grids with 643, 1283, 2563 cells at various Reynolds numbers corresponding to both laminar ( Re =100,280) and turbulent ( Re =1600,4000) vortex decay scenarios. The features of the numerical method are discussed in terms of the kinetic energy dissipation rate and integral enstrophy curves, temporal evolution of the spanwise vorticity, energy spectra and spatial correlation functions.Graphical abstract: [ABSTRACT FROM AUTHOR]