The present study investigates the vibration analysis of cylindrical shells composed of fiber metal laminate (FML) with embedded piezoelectric layers, undergoing fluid-structure interaction (FSI) and resting on a Past...
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The present study investigates the vibration analysis of cylindrical shells composed of fiber metal laminate (FML) with embedded piezoelectric layers, undergoing fluid-structure interaction (FSI) and resting on a Pasternak elastic foundation based on the principles of three-dimensional elasticity theory. Using the state space approach, the equations of motion were derived under simply supported boundary conditions. The natural frequencies of the FML cylindrical shell, accounting for the presence of a moving fluid, were computed by solving the eigenfrequency equations. The study examined the influence of various parameters, including boundary conditions, length-to-radius ratio, fluid type, fluid velocity, circumferential wave number, and radius-to-thickness ratio, on glass-reinforced aluminum laminate (GLARE), aramid-reinforced aluminum laminate (ARALL), and carbon-reinforced aluminum laminate (CARALL). A constant composite/metal volume ratio was assumed. The results obtained were validated by comparing with natural frequency values from the existing literature, confirming the agreement and convergence with previous studies. The results confirm that the highest natural frequency values are assigned to the CARALL, ARALL and GRALE structures in descending order. Furthermore, an increase in fluid flow velocity through the cylindrical shell correlates with a reduction in natural frequency.
Unfitted mesh finite element approximations of immersed incompressible fluid-structure interaction problems which efficiently avoid strong coupling without compromising stability and accuracy are rare in the literatur...
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Unfitted mesh finite element approximations of immersed incompressible fluid-structure interaction problems which efficiently avoid strong coupling without compromising stability and accuracy are rare in the literature. Moreover, most of the existing approaches introduce additional unknowns or are limited by penalty terms which yield ill-conditioning issues. In this paper, we introduce a new unfitted mesh semi-implicit coupling scheme which avoids these issues. To this purpose, we provide a consistent generalization of the projection based semi-implicit coupling paradigm of (Int. J. Num. Meth. Engg., 69(4):794-821, 2007) to the unfitted mesh Nitsche-extended-FEM framework.
In this work, we address the problem of fluid-structure interaction (FSI) with moving structures that may come into contact. We propose a penalization contact algorithm implemented in an unfitted numerical framework d...
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In this work, we address the problem of fluid-structure interaction (FSI) with moving structures that may come into contact. We propose a penalization contact algorithm implemented in an unfitted numerical framework designed to treat large displacements. In the proposed method, the fluid mesh is fixed and the structure meshes are superimposed to it without any constraint on the conformity. Thanks to the Extended Finite Element Method (XFEM), we can treat discontinuities of the fluid solution on the mesh elements intersecting the structure. The coupling conditions at the fluid-structure interface are enforced via a discontinuous Galerkin mortaring technique, which is a penalization method that ensures the consistency of the scheme with the underlining problem. Concerning the contact problem, we consider a frictionless contact model in a master/slave approach. By considering the coupled FSI-contact problem, we perform some numerical tests to assess the sensitivity of the proposed method with respect to the discretization and contact parameters and we show some examples in the case of contact between a flexible body and a rigid wall and between two deformable structures.
The present numerical study explores the performance of fluid-structure interaction (FSI) in a microchannel with an oscillating elastic wall. A two-dimensional (2D) Computational fluid Dynamics (CFD) simulation was pe...
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The present numerical study explores the performance of fluid-structure interaction (FSI) in a microchannel with an oscillating elastic wall. A two-dimensional (2D) Computational fluid Dynamics (CFD) simulation was performed to investigate the influence of the elastic wall's frequency and amplitude on fluid flow behavior, pressure drop, and heat transfer enhancement. The FSI governing equations were solved using the Arbitrary Lagrangian-Eulerian (ALE) method. The results indicated that the Nusselt number (Nu) decreases as oscillation frequency increases. In contrast, the Nu increased linearly with the oscillation amplitude. Additionally, the Prandtl number (Pr) showed an insignificant influence on the Nu number for the studied operating range. An optimal operating condition was identified for the microchannel with an oscillating wall, achieving a spatial average Nu number of 16.796 compared to 14.577 for a simple microchannel channel, representing a 15.23 %% enhancement in heat transfer. A correlation is derived for the spatial average Nu number as a function of the Reynolds number (Re), Strouhal number (St), Pr, and vibration amplitude ratio, providing a valuable tool for designing and optimizing microchannel systems with FSI. Finally, the Maxwell boundary conditions are incorporated into the simulation of a microchannel with a vibrating upper wall to evaluate the slip conditions.
Transcatheter aortic valve replacement (TAVR) strongly depends on the calcification patterns, which may lead to a malapposition of the stented valve and complication onsets in terms of structure kinematics and paraval...
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Transcatheter aortic valve replacement (TAVR) strongly depends on the calcification patterns, which may lead to a malapposition of the stented valve and complication onsets in terms of structure kinematics and paravalvular leakage (PVL). From one anatomical-resembling model of the aortic root, six configurations with different calcific deposits were built. TAVR fluid-structure interaction simulations predicted different outcomes for the different calcifications patterns in terms of the final valve configuration in the implantation site and the PVL estimations. In particular models with deposits along the cups coaptation resulted in mild PVL, while those with deposits along the attachment line in moderate PVL.
A computational method of fluid-structure coupling is implemented to predict the fatigue response of a high-pressure turbine blade. Two coupling levels, herein referred to as a "fully coupled" and "deco...
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A computational method of fluid-structure coupling is implemented to predict the fatigue response of a high-pressure turbine blade. Two coupling levels, herein referred to as a "fully coupled" and "decoupled" methods are implemented to investigate the influence of multi-physics interaction on the 3 D stress state and fatigue response of a turbine blade. In the fully-coupled approach, the solutions of the fluid-flow and the solid-domain finite element problem are obtained concurrently, while in the decoupled approach, the independently computed aerodynamic forces are unilaterally transferred as boundary conditions in the subsequent finite element solution. In both cases, a three-dimensional unsteady stator-rotor aerodynamic configuration is modelled to depict a forced-vibration loading of high-cycle failure mode. Also analyzed is the low-cycle phenomenon which arises due to the mean stresses of the rotational load of the rotating turbine wheel. The coupling between the fluid and solid domains (fully-coupled approach) provides a form of damping which reduces the amplitude of fluctuation of the stress history, as opposed to the decoupled case with a resultant higher amplitude stress fluctuation. While the stress amplitude is higher in the decoupled case, the fatigue life-limiting condition is found to be significantly influenced by the higher mean stresses in the fully-coupled method. The differences between the two approaches are further explained considering three key fatigue parameters;mean stress, multiaxiality stress state and the stress ratio factors. The study shows that the influence of the coupling between the fluid and structures domain is an important factor in estimating the fatigue stress history.
In this paper, a new take on the concept of an active subspace for reducing the dimension of the design parameter space in a multidisciplinary analysis and optimization (MDAO) problem is proposed. The new approach is ...
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In this paper, a new take on the concept of an active subspace for reducing the dimension of the design parameter space in a multidisciplinary analysis and optimization (MDAO) problem is proposed. The new approach is intertwined with the concepts of adaptive parameter sampling, projection-based model order reduction, and a database of linear, projection-based reduced-order models equipped with interpolation on matrix manifolds, in order to construct an efficient computational framework for MDAO. The framework is fully developed for MDAO problems with linearized fluid-structure interaction constraints. It is applied to the aeroelastic tailoring, under flutter constraints, of two different flight systems: a flexible configuration of NASA's Common Research Model;and NASA's Aeroelastic Research Wing #2 (ARW-2). The obtained results illustrate the feasibility of the computational framework for realistic MDAO problems and highlight the benefits of the new approach for constructing an active subspace in both terms of solution optimality and wall-clock time reduction.
Analytical solution for vibration analysis of orthotropic and FGM submerged cylindrical shell containing a surface crack of variable angular orientation is presented in this work. The governing equations in terms of t...
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Analytical solution for vibration analysis of orthotropic and FGM submerged cylindrical shell containing a surface crack of variable angular orientation is presented in this work. The governing equations in terms of transverse deflection of cracked-submerged shell have been derived using classical shell theory. The fluid forces associated with its inertial effects are added in the governing differential equation to incorporate the fluid-structure interaction effect. The line spring model (LSM) is used to formulate the crack coefficients to accommodate the effect of crack in the governing equation. Furthermore, the governing equation is solved using Donell-Mushtari-Vlasov (DMV) theory to get the fundamental frequency. The results are presented for frequency by giving the input parameters as crack length, crack orientation, and shell's physical properties such as radius, thickness, and length of the *** by Wei-Chau Xie
Purpose The purpose of this exhaustive experimental study is to investigate the fluid-structure interaction in the flexible membrane wings over a range of angles of attack for various Reynolds numbers. Design/methodol...
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Purpose The purpose of this exhaustive experimental study is to investigate the fluid-structure interaction in the flexible membrane wings over a range of angles of attack for various Reynolds numbers. Design/methodology/approach In this paper, an experimental study on fluid-structure interaction of flexible membrane wings was presented at Reynolds numbers of 2.5 x 10(4), 5 x 10(4) and 7.5 x 10(4). In the experimental studies, flow visualization, velocity and deformation measurements for flexible membrane wings were performed by the smoke-wire technique, multichannel constant temperature anemometer and digital image correlation system, respectively. All experimental results were combined and fluid-structure interaction was discussed. Findings In the flexible wings with the higher aspect ratio, higher vibration modes were noticed because the leading-edge separation was dominant at lower angles of attack. As both Reynolds number and the aspect ratio increased, the maximum membrane deformations increased and the vibrations became visible, secondary vibration modes were observed with growing the leading-edge vortices at moderate angles of attack. Moreover, in the graphs of the spectral analysis of the membrane displacement and the velocity;the dominant frequencies coincided because of the interaction of the flow over the wings and the membrane deformations. Originality/value Unlike available literature, obtained results were presented comparatively using the sketches of the smoke-wire photographs with deformation measurement or turbulence statistics from the velocity measurements. In this study, fluid-structure interaction and leading-edge vortices of membrane wings were investigated in detail with increasing both Reynolds number and the aspect ratio.
In this paper, the modelling strategies of fluid-structure interaction impact simulation between amphibious aircraft float structure and water are investigated. fluid-structure interaction in the form of constant velo...
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In this paper, the modelling strategies of fluid-structure interaction impact simulation between amphibious aircraft float structure and water are investigated. fluid-structure interaction in the form of constant velocity hydrodynamic impact was numerically modelled using finite element software by employing the coupled Eulerian-Lagrangian method. Four types of modelling strategies of the float, i.e., (1) full shell, (2) full solid, (3) multi-stage multi-scale, and (4) concurrent multi-scale modelling, are implemented and compared to obtain the most accurate model to obtain stress distribution on the float structure components. The modelling procedure and the advantages and disadvantages of each strategy are discussed comprehensively. The results show that the simulation using the structure modelled as shell elements is the most accurate strategy to obtain stress distribution on the float structure components while the solid elements model is the worst since the stresses predicted by using this model is lower than that of the shell elements model, especially when insufficient elements in the thickness direction is used. The multi-stage multi-scale in terms of shell-to-solid sub-modelling can be an alternative strategy since the results are similar to that using the shell geometry model. The concurrent multi-scale modelling, on the other hand, predicts acceptable stress values with a reasonable computational resource while maintaining computational accuracy and efficiency.
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