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Rain-wind induced vibrations are a vibration phenomenon that occurs when rain and wind act simultaneously on cables, hangars and ropes. The vibration phenomena may induce oscillations with large amplitudes, thus the fatigue of construction elements is possible. The paper presents a possible fluid-mechanical interpretation of rain-wind induced vibrations. Based on this interpretation a mechanical model is deduced, in order to enable numerical investigations. In order to account for the unsteady aerodynamics a hybrid method is used, which records the lift and drag coefficients as well as the distributions of pressure and shear stress from experiments in the wind tunnel. The complex system of nonlinear differential equations is analysed concerning the stability of solutions. The limits between numerical and experimental investigations are shown using the example of the equilibrium positions of the rivulets for various angles of incidence. [ABSTRACT FROM AUTHOR]

An one-dimensional hybrid model of RF discharge in low-temperature argon plasma is presented in our paper. The hybrid model consists of two parts—particle model which simulates fast electrons while fluid model simulates slow electrons and positive argon ions. In the particle model the positions and velocities of fast electrons are calculated by means of deterministic Verlet algorithm while the collision processes are treated by the stochastic way. For the solution of fluid equations, for slow electrons and positive argon ions, the Scharfetter-Gummel exponential algorithm was used. Typical results of our calculations presented in this paper are total RF current and RF voltage waveforms on the planar substrate immersed into argon plasma. The next results which can be found here are the ion, electron and displacement current waveforms on the substrate. Especially, the knowledge of waveform of the ion current is very important for experimental physicists during the deposition of thin films. [ABSTRACT FROM AUTHOR]