Data Transfer Schemes in Rotorcraft Fluid-Structure Interaction Predictions

For a CFD (computation fluid dynamics)/CSD (computational structural dynamics) coupling, appropriate data exchange strategy is required for the successful operation of the coupling computation, due to fundamental differences between CFD and CSD analyses. This study aims at evaluating various data transfer schemes of a loose CFD/CSD coupling algorithm to validate the higher harmonic control aeroacoustic rotor test (HART) data in descending flight. Three different data transfer methods in relation to the time domain airloads are considered. The first (method 1) uses random data selection matched with the timewise resolution of the CSD analysis whereas the last (method 2) adopts a harmonic filter to the original signals in CFD and CSD analyses. The second (method 3) is a mixture of the two methods. All methods lead to convergent solutions after a few cycles of coupling iterations are marched. The final converged solutions for each of the data transfer methods are correlated with the measured HART data. It is found that both method 1 and method 2 exhibit nearly identical results on airloads and blade motions leading to excellent correlations with the measured data while the agreement is less satisfactory with method 3. The reason of the discrepancy is identified and discussed illustrating CFD-/CSD-coupled aeromechanics predictions.

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Study on Data Transfer Methods for Fluid-Structure Interaction Analysis

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.255-260.3579 ◽

2011 ◽

Vol 255-260 ◽

pp. 3579-3583

Author(s):

Bo Su ◽

Ruo Jun Qian ◽

Xiang Ke Han

Keyword(s):

Data Exchange ◽

Data Transfer ◽

Interaction Analysis ◽

Fluid Structure Interaction ◽

Induced Response ◽

Response Analysis ◽

Fluid Structure ◽

Structure Interaction ◽

Compactly Supported ◽

Transfer Method

The data transfer method for fluid structure interaction analysis using compactly supported radial based function (CRBF-FSI) is studied. It builds transfer matrix for data exchange and makes fluid and structure mesh use different shape and density unrestrictedly. Example of data exchange on 3D interface is studied. The efficient and the accurate of CRBF-FSI method are analyzed and also the influence of different compactly-supported radius is studied. The results show that CRBF-FSI method is suitable for FSI data transfer on complicated interface if compactly-supported radius is properly chosen. It has a bright future in practical use such as wind-induced response analysis in Wind Engineering.

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Effects of higher harmonic control on rotor performance and control loads

Journal of Aircraft ◽

10.2514/3.46166 ◽

1992 ◽

Vol 29 (3) ◽

pp. 336-342 ◽

Cited By ~ 13

Author(s):

Khanh Nguyen ◽

Inderjit Chopra

Keyword(s):

Harmonic Control ◽

Higher Harmonic Control ◽

Higher Harmonic ◽

And Control

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Approximate Degree Reduction of NURBS Curves and Surfaces: An Integrated Approach

4th Flexible Assembly Conference ◽

10.1115/detc1994-0368 ◽

1994 ◽

Author(s):

Srinivasa P. Varanasi ◽

Athamaram H. Soni

Keyword(s):

Shape Control ◽

Data Exchange ◽

Data Transfer ◽

Integrated Approach ◽

Free Form ◽

Aircraft Industry ◽

Trimmed Surfaces ◽

Curves And Surfaces ◽

High Degree ◽

Boundary Curves

Abstract Data exchange between different CAD systems usually requires conversion between different representations of free-form curves and surfaces. Also, trimmed surfaces give rise to high degree boundary curves. Accurate conversion of these forms becomes necessary for reliable data transfer. Also important is the issue of shape control, specially in the aircraft industry. The objective of this paper is to investigate conversion methods and effect of shape control on the design and choice of such methods.

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JCAMP-DX for NMR

Applied Spectroscopy ◽

10.1366/0003702934067874 ◽

1993 ◽

Vol 47 (8) ◽

pp. 1093-1099 ◽

Cited By ~ 29

Author(s):

Antony N. Davies ◽

Peter Lampen

Keyword(s):

Spectral Data ◽

Data Exchange ◽

Data Transfer ◽

Nmr Imaging ◽

Successful Implementation ◽

Independent Data ◽

Imaging Data ◽

Loss Of Information ◽

Storage Media ◽

Different Origin

Following the development and publication of the JCAMP-DX protocol 4.24 and its successful implementation in the field of infrared spectroscopy, data exchange without loss of information, between systems of different origin and internal format, has become a reality. The benefits of this system-independent data transfer standard have been recognized by workers in other areas who have expressed a wish for an equivalent, compatible standard in their own fields. This publication details a protocol for the exchange of Nuclear Magnetic Resonance (NMR) spectral data without any loss of information and in a format that is compatible with all storage media and computer systems. The protocol detailed below is designed for spectral data transfer, and its use for NMR imaging data transfer has not as yet been investigated.

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Emergency Gate Vibration of the Pipe-Turbine Model

Shock and Vibration ◽

10.1155/2000/406976 ◽

2000 ◽

Vol 7 (1) ◽

pp. 3-13 ◽

Cited By ~ 1

Author(s):

Andrej Predin ◽

Roman Klasinc

Keyword(s):

Data Transfer ◽

Guide Vane ◽

Natural Vibrations ◽

Vibration Behavior ◽

Kaplan Turbine ◽

Gate Opening ◽

Horizontal Shaft ◽

Dynamic Similitude ◽

The Moment ◽

The Time Domain

The vibration behavior of an emergency gate situated on a horizontal-shaft Kaplan turbine is studied. The analysis and transfer of the dynamic movements of the gate are quite complex. In particular the behavior is examined of the emergency gate for the case when the power unit is disconnected from the system or there is a breakdown of the guide vane system at the moment when the maximal head and capacity are achieved. Experimental-numerical methods both in the time domain and in the frequency domain are employed. Natural vibrations characterize a first zone, corresponding to relatively small gate openings. As the gate opening increases, the vibration behavior of the gate becomes increasingly dependent on the swirl pulsations in the draft tube of the turbine. Finally, the data transfer from the model to the prototype by use of the dynamic similitude law is discussed.

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Using Mobile Elements as Dynamic Bridges in Sparse Wireless Sensor Networks

Research and Development on Information and Communication Technology ◽

10.32913/mic-ict-research.v3.n11.309 ◽

2014 ◽

pp. 107

Author(s):

Hoang Dang Hai ◽

Thorsten Strufe ◽

Pham Thieu Nga ◽

Hoang Hong Ngoc ◽

Nguyen Anh Son ◽

...

Keyword(s):

Wireless Sensor Networks ◽

Sensor Networks ◽

Data Exchange ◽

Data Transfer ◽

Mobile Elements ◽

Sensor Nodes ◽

Pollution Monitoring ◽

Wireless Sensor ◽

Mobile Nodes ◽

Road Distance

Sparse Wireless Sensor Networks using several mobile nodes and a small number of static sensor nodes have been widely used for many applications, especially for traffic-generated pollution monitoring. This paper proposes a method for data collection and forwarding using Mobile Elements (MEs), which are moving on predefined trajectories in contrast to previous works that use a mixture of MEsand static nodes. In our method, MEscan be used as data collector as well as dynamic bridges for data transfer. We design the trajectories in such a way, that they completely cover the deployed area and data will be gradually forwarded from outermost trajectories to the center whenever a pair of MEs contacts each other on an overlapping road distance of respective trajectories. The method is based on direction-oriented level and weight assignment. We analyze the contact opportunity for data exchange while MEs move. The method has been successfully tested for traffic pollution monitoring in an urban area.

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A fluid-structure interaction analysis of the human aortic arch under inertial load

10.32920/ryerson.14653443.v1 ◽

2021 ◽

Author(s):

Jonathan M Zalger

Keyword(s):

Mass Flow ◽

Data Transfer ◽

Interaction Analysis ◽

Fluid Structure Interaction ◽

Longitudinal Axis ◽

Tissue Response ◽

Upper Body ◽

Inertial Load ◽

Fluid Structure ◽

Structure Interaction

Presented is an investigation into the use of numerical methods for modelling the effects of inertial load on the human cardiovascular system. An anatomically correct geometry was developed based on three-dimensional computed tomography (CT) data and independent meshes were created for the solid and fluid regimes. These domains were simulated using independent solvers and subsequently coupled using an intermediate data transfer alogrithm. At the inlet of the arch, a pulsatile velocity boundary condition was enforced replicating the cardiac cycle. Time invariant, resistive boundary conditions were used at all outlets and a linear isotropic constitutive model was used for tissue response. Verification was conducted by comparing simulation results at standard earth gravity (9.81 m/s²) with published values for velocity, mass flow rate, deformation, and qualitative flow behaviour. The presented fluid-structure interaction (FSI) model shows strong agreement with accepted normal values. Inertial load was then applied along the longitudinal axis of the arch in multiples of standard gravity to a maximum of 8+Gz. This load increased arch flow velocities, and reduced mass flow in the ascending brachiocephalic and carotid arteries. Blood flow from the arch to the upper body and brain ceased near 8+Gz. Although the presented results are preliminary, the feasibility of such an analysis has been successfully demonstrated.

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Drilling Riser Disconnection Challenges in Ultra-Deep Water

Volume 1: Offshore Technology ◽

10.1115/omae2018-77115 ◽

2018 ◽

Author(s):

Alexandre Diezel ◽

Germain Venero ◽

Victor Gomes ◽

Leandro Muniz ◽

Rafael Fachini ◽

...

Keyword(s):

Good Representation ◽

Regular Wave ◽

Computational Simulations ◽

Successful Operation ◽

Dynamic Positioning System ◽

Drilling Rig ◽

Wave Approach ◽

Short Period ◽

Drilling Operations ◽

The Time Domain

With the extension of the offshore drilling operations to water depths of 10,000 ft and beyond, the technical challenges involved also increased considerably. In this context, the management of the riser integrity through the application of computational simulations is capital to a safe and successful operation — particularly in harsh environments. One of the main challenges associated with keeping the system under safe limits is the recoil behavior in case of a disconnection from the well. The risk that an emergency disconnect procedure can take place during the campaign is imminent, either due to failure of the dynamic positioning system or due to extreme weather in such environments. Recent work [1] in the field of drilling riser dynamic analysis has shown that the recoil behavior of the riser after a disconnection from the bottom can be one of the main drivers of the level of top tension applied. Tension fluctuations can be very large as the vessel heaves, especially in ultra-deep waters where the average level of top tension is already very high. In order to be successful, a safe disconnection must ensure that the applied top tension is sufficient for the Lower Marine Riser Package (LMRP) to lift over the Blow-Out Preventer (BOP) with no risk of interference between the two. This tension should also not exceed a range in which the riser will not buckle due to its own recoil, that the telescopic joint will not collapse and transfer undesirable loads onto the drilling rig or that the tensioning lines will not compress. A good representation of such behavior in computational simulations is therefore very relevant to planning of the drilling campaign. A case study is presented herein, in which a recoil analysis was performed for a water depth of 11,483ft (3,500m). Numerical simulations using a finite element based methodology are applied for solving the transient problem of the riser disconnection in the time domain using a regular wave approach. A detailed hydro-pneumatic tensioning system model is incorporated to properly capture the effect of the anti-recoil valve closure and tension variations relevant during the disconnection. A reduction of conservativism is applied for the regular wave approach, where the maximum vessel heave likely to happen in every 50 waves is applied instead of the usual maximum in 1000 waves approach. ISO/TR 13624-2 [4] states that using the most probable maximum heave in 1000 waves is considered very conservative, as the event of the disconnection takes place in a very short period of time. The challenges inherent to such an extreme site are presented and conclusions are drawn on the influence of the overall level of top tension in the recoil behavior.

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On Vessel Motion Induced Vortex-Induced Vibrations of a Steel Lazy Wave Riser

10.1115/omae2021-60371 ◽

2021 ◽

Author(s):

Decao Yin

Keyword(s):

Vortex Shedding ◽

Time Domain ◽

Oscillatory Flow ◽

Domain Model ◽

Time Varying ◽

Structure Interaction ◽

Response Characteristics ◽

Vortex Induced Vibrations ◽

The Time Domain ◽

Vessel Motion

Abstract Deepwater steel lazy wave risers (SLWR) subject to vessel motion will be exposed to time-varying oscillatory flow, vortices could be generated and the cyclic vortex shedding force causes the structure vibrate, such fluid-structure interaction is called vortex-induced vibrations (VIV). To investigate VIV on a riser with non-linear structures under vessel motion and oscillatory flows, time domain approaches are needed. In this study, a time-domain approach is used to simulate a full-scale SLWR. Two cases with simplified riser top motions are simulated numerically. By using default input parameters to the time domain approach, the key oscillatory flow induced VIV response characteristics such as response frequency, curvature and displacements are examined and discussed. More accurate VIV prediction could be achieved by using realistic hydrodynamic inputs into the time domain model.

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