This paper presents a discrete sliding mode observer (DSMO) for state estimation of a class of a second order underactuated system. The estimated states are used to implement the discrete sliding mode control (DSMC). Modified Bartoszewicz’s reaching law is used to synthesize a DSMC. A partially filled liquid container motion coupled with liquid slosh constitutes a class of second order underact...

Time-resolved variations of the ion velocity distribution function (IVDF) are measured in the cylindrical Hall thruster using a novel heterodyne method based on the laser-induced fluorescence technique. This method consists in inducing modulations of the discharge plasma at frequencies that enable the coupling to the breathing mode. Using a harmonic decomposition of the IVDF, one can extract ea...

Violent fluid motions, high speed marine vehicles and Computational Fluid Dynamics (CFD) are selected as main topics. Violent fluid motions deal with green water on deck, sloshing and slamming. Slamming involves many physical effects. When analyzing slamming, one must always have the structural reaction in mind. This necessitates that hydroelastic effects are considered. Many hydrodynamic pheno...

A numerical method for the simulation of three-dimensional incompressible twophase flows is presented. The proposed algorithm combines an implicit pressure stabilized finite element method for the solution of incompressible two-phase flow problems with a level set method implemented with a quadrature-free Discontinuous Galerkin (DG) method [1]. The use of a fast contouring algorithm [2] permits...

Abstract Sloshing is the violent motion of a resonant fluid in moving tank. When moves and interacts with tank, dynamic pressure from such an interaction can cause large deformations tank walls structure. In this study, 3D numerical simulation was carried out five variations LNG ship model: prismatic, rectangular, tube, spherical, new model filling ratio 25%. Forced oscillation roll f = 1.04 Hz...

This study investigates the effect of nonlinear strengths sloshing on damping performance side-mounted perforated baffles and discusses influence resonance characteristics flow. The model score is adopted to evaluate strength water sloshing. A microscopic a volume-averaged macroscopic are established simulate flow in two-dimensional (2D) tank with baffles. In addition, series experimental tests...

Abstract In this paper, a nonlinear reduced-order model based on neural networks is introduced in order to vertical sloshing presence of Rayleigh–Taylor instability the free surface for use fluid–structure interaction simulations. A box partially filled with water, representative wing tank, first set harmonic motion via controlled electrodynamic shaker. Accelerometers and load cells at interfac...

Chandra X-ray observations revealed the presence of cold fronts – sharp contact discontinuities between gas regions with different temperatures and densities – in the centers of many, if not most, relaxed clusters with cool cores. We use high-resolution simulations of idealized cluster mergers to address the origin of such fronts. Typical observed gas density and temperature profiles are used a...

Abstract All aircraft are subject to a range of loading throughout ground and flight operations, which ultimately define the sizing weight structure. Active passive loads alleviation technologies provide an approach reduce dynamic arising from atmospheric gusts turbulence, leading more fuel-efficient designs. Within H2020 SLOWD project, fuel sloshing is being considered as method for alleviatin...