Computational Fluid-Structure Interaction of DGB Parachutes in Compressible Fluid Flow

2010 ◽  
Author(s):  
Carlos Pantano-Rubino ◽  
Kostas Karagiozis ◽  
Ramji Kamakoti ◽  
Fehmi Cirak
Keyword(s):  
Adaptive Mesh Refinement ◽  
Compressible Flows ◽  
Large Scale ◽  
Structural Model ◽  
Fluid Model ◽  
Fluid Structure Interaction ◽  
Adaptive Mesh ◽  
Turbulent Wake ◽  
Fluid Structure ◽  
Structure Interaction

This paper describes large-scale simulations of compressible flows over a supersonic disk-gap-band parachute system. An adaptive mesh refinement method is used to resolve the coupled fluid-structure model. The fluid model employs large-eddy simulation to describe the turbulent wakes appearing upstream and downstream of the parachute canopy and the structural model employed a thin-shell finite element solver that allows large canopy deformations by using subdivision finite elements. The fluid-structure interaction is described by a variant of the Ghost-Fluid method. The simulation was carried out at Mach number 1.96 where strong nonlinear coupling between the system of bow shocks, turbulent wake and canopy is observed. It was found that the canopy oscillations were characterized by a breathing type motion due to the strong interaction of the turbulent wake and bow shock upstream of the flexible canopy.

Multi-Scale Fluid-Structure Interaction Simulations Based on Mesoscopic Approaches

2014 ◽  
Author(s):  
Todd H. Weisgraber ◽  
Stuart D. C. Walsh ◽  
Kostas Karazis ◽  
Dennis Gottuso
Keyword(s):  
Turbulent Flows ◽  
Adaptive Mesh Refinement ◽  
Fluid Structure Interaction ◽  
Adaptive Mesh ◽  
Dynamics Modeling ◽  
Spacer Grid ◽  
Fluid Structure ◽  
Structure Interaction ◽  
Numerical Effort ◽  
High Reynolds

Many challenging fluid-structure interaction problems in nuclear engineering remain unresolved because current CFD methodologies are unable to manage the number of computational cells needed and/or the difficulties associated with meshing changing geometries. One of the most promising recent methodologies for fluid dynamics modeling is the lattice-Boltzmann method — an approach that offers significant advantages over classical CFD methodologies by 1) greatly reducing meshing requirements, 2) offering great scalability, and 3) through relative ease of code parallelization. While LBM often requires increased numerical effort compared to other methods, this can be dramatically reduced by combining LBM with Adaptive Mesh Refinement (LB-AMR). This study describes an ongoing collaboration investigating nuclear fuel-assembly spacer grid performance. The LB-AMR method, used to simulate the flow field around a specific spacer grid design, is capable of describing turbulent flows for high Reynolds numbers, revealing rich flow dynamics in good qualitative agreement with experimental results. Prepared by LLNL under Contract DE-AC52-07NA27344.

scholarly journals On the combined flow and structural measurements via Robotic Volumetric PTV

2021 ◽  
Author(s):  
Francesco Mario Antonio Mitrotta ◽  
Jurij Sodja ◽  
Andrea Sciacchitano
Keyword(s):  
Particle Tracking ◽  
Large Scale ◽  
Structural Model ◽  
Fluid Structure Interaction ◽  
Small Scale ◽  
Flexible Plate ◽  
Fluid Structure ◽  
Structure Interaction ◽  
Combined Flow ◽  
Measurement Approach

Abstract This study describes a novel measurement approach for combined flow and structural measurements in wind tunnels using Robotic Volumetric PTV. The measurement approach is based on the application of a particle tracking algorithm on images including flow or structure tracers, where the latter are implemented by means of fiducial markers. The main steps of the measurement procedure comprise the simultaneous acquisition of flow and structure tracers in the same images, the distinction of the tracers leading to separate flow and structure image sets, the application of Lagrangian Particle Tracking and the further post-processing, and recombination of the obtained data. The approach is applied to the fluid-structure interaction between a flexible plate with a span of 1.2 m and a periodic gust. The total measurement volume amounts approximately to 150 liters. A phase-averaged description of the fluid-structure interaction problem is presented, with the focus on the effects of the spatio-temporal averaging of the flow information. The structural displacements obtained from the PTV system are validated against a scanning vibrometer. The phase-averaged displacement of the markers is also analyzed, assessing both the validity of the phase-averaged approach and the physical coherence of their motion with respect to a structural model of the plate. It is found that Robotic Volumetric PTV is suitable for the measurement of large-scale structural displacements, while it should not be used to measure small-scale vibrations. Finally, a visualization of the combined measurement is presented, together with an analysis of the consistency between the measured structure and flow field.

Optimization of Vibration Reduction in a Helicopter Blade With 2 Way Fluid-Structure Interaction

2018 ◽  
Author(s):  
Mürüvvet Sinem Sicim ◽  
Metin Orhan Kaya
Keyword(s):  
Cantilever Beam ◽  
Fiber Orientation ◽  
Structural Model ◽  
Fiber Composite ◽  
Vibration Reduction ◽  
Fluid Structure Interaction ◽  
Fluid Structure ◽  
Helicopter Blade ◽  
Structure Interaction ◽  
Blade Model

The main goal of this study is the optimization of vibration reduction on helicopter blade by using macro fiber composite (MFC) actuator under pressure loading. Due to unsteady aerodynamic conditions, vibration occurs mainly on the rotor blade during forward flight and hover. High level of vibration effects fatigue life of components, flight envelope, pleasant for passengers and crew. In this study, the vibration reduction phenomenon on helicopter blade is investigated. 3D helicopter blade model is used to perform the aeroelastic behavior of a helicopter blade. Blade design is created by Spaceclaim and finite element analysis is conducted by ANSYS 19.0. Generated model are solved via Fluent by using two-way fluid-solid coupling analysis, then the analyzed results (all aerodynamic loads) are directly transferred to the structural model. Mechanical results (displacement etc.) are also handed over to the Fluent analysis by helping fluid-structure interaction interface. Modal and harmonic analysis are performed after FSI analysis. Shark 120 unmanned helicopter blade model is used with NACA 23012 airfoil. The baseline of the blade structure consists of D spar made of unidirectional Glass Fiber Reinforced Polymer +45°/−45° GFRP skin. MFC, which was developed by NASA’s Langley Research Center for the shaping of aerospace structures, is applied on both upper and lower surfaces of the blade to reduce the amplitude in the twist mode resonant frequency. D33 effect is important for elongation and to observe twist motion. To foresee the behavior of the MFC, thermo-elasticity analogy approach is applied to the model. Therefore, piezoelectric voltage actuation is applied as a temperature change on ANSYS. The thermal analogy is validated by using static behavior of cantilever beam with distributed induced strain actuators. Results for cantilever beam are compared to experimental results and ADINA code results existing in the literature. The effects of fiber orientation of MFC actuator and applied voltage on vibration reduction on helicopter blade are represented. The study shows that torsion mode determines the optimum placement of actuators. Fiber orientation of the MFC has few and limited influences on results. Additionally, the voltage applied on MFC has strong effects on the results and they must be selected according to applied model.

Study on Similar Skills of Dynamic Model Test Concerning Fluid-Structure Interaction for Water-Conveyance Tunnel in Soft Soil

2010 ◽  
Vol 29-32 ◽  
pp. 1458-1463 ◽  
Author(s):  
Jin Yun Liu ◽  
Jian Yun Chen
Keyword(s):  
Numerical Simulation ◽  
Model Test ◽  
Structural Model ◽  
Soft Soil ◽  
Fluid Structure Interaction ◽  
Similar Relationship ◽  
Fluid Structure ◽  
Structure Interaction ◽  
Water Conveyance ◽  
Water Conveyance Tunnel

Three basic types of similar relationship between the prototype and the model for dynamic structural model test and dynamic destructive model test were proposed in corresponding literatures. At the time the situation where various similar relationships are applicable and the technique to ensure similarity for the different goal was discussed. Here the numerical simulation of model test of water-conveyance tunnel concerning fluid-structure interaction in soft soil is studied. Based on economy and practicability of selective material for model test, the similar relationship and the technique are proposed, which are validated through the example. The results of numerical simulation show: under the specific conditions, data of the model test can completely transfer to those of the prototype by use of this type of similar skill, and get more useful information. Some new ideas are introduced to keep the similarity of the hydro-structure structures.

Sign in / Sign up

Export Citation Format

Share Document