Готові списки джерел за темами / Langrangian approach

Добірка наукової літератури з теми "Langrangian approach"

Автор: Grafiati
Опубліковано: 14 березня 2023

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Статті в журналах з теми "Langrangian approach"

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Lai, Chun-Ta, Gabriel Katul, David Ellsworth, and Ram Oren. "Modelling Vegetation-Atmosphere Co2 Exchange By A Coupled Eulerian-Langrangian Approach." Boundary-Layer Meteorology 95, no. 1 (April 2000): 91–122. http://dx.doi.org/10.1023/a:1002473906184.

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2

COTE, J. "A Lagrange multiplier approach for the metric terms of semi-Langrangian models on the sphere." Quarterly Journal of the Royal Meteorological Society 114, no. 483 (July 15, 1988): 1347–52. http://dx.doi.org/10.1256/smsqj.48309.

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3

Gług, Maciej, and Jarosław Wąs. "Modeling of oil spill spreading disasters using combination of Langrangian discrete particle algorithm with Cellular Automata approach." Ocean Engineering 156 (May 2018): 396–405. http://dx.doi.org/10.1016/j.oceaneng.2018.01.029.

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4

Minh Thanh, Vu, Sigit P. Santosa, Djarot Widagdo, and Ichsan Setya Putra. "Steel Plate Behavior under Blast Loading-Numerical Approach Using LS-DYNA." Applied Mechanics and Materials 842 (June 2016): 200–207. http://dx.doi.org/10.4028/www.scientific.net/amm.842.200.

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Plate is one of the most common structural elements, which appears in a wide range of applications: steel bridges, blast-resistance door, and armored vehicles. In this paper, the behavior of steel plates under blast loading was studied through numerical approaches using LS DYNA and then the results were compared with the experiment results obtained from existing literatures. The study of a clamped square plate exposed to blast loading in three distinct stand-off distances. Three different methods of modeling blast loading were used, namely: empirical blast method, arbitrary Lagrangian Eulerian (ALE) method, and coupling of Lagrangian and Eulerian method. The empirical blast method was deployed by using key card *LOAD_BLAST in LS-DYNA. In ALE method, Langrangian and Eulerian solution were combined in the same model and the fluid-structure interaction (FSI) handled by coupling algorithm. In coupling method, the engineering load blast in LS-DYNA (*LOAD_BLAST_ENHANCED) was coupled with the ALE solver. In terms of central deflection and computational time, the coupling method appeared to be the best method which is very time-effective and showed a good correlation with the experiment data.
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5

Sidebang, Wiwin Roslinda, Ade Ali Nurdin, and Mochamad Edman Syarief. "Pengaruh ROE dan DER Terhadap Dividend Payout Ratio pada Industri Barang Konsumsi di Bursa Efek Indonesia." Indonesian Journal of Economics and Management 2, no. 3 (July 24, 2022): 599–613. http://dx.doi.org/10.35313/ijem.v2i3.3163.

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This research was conducted the Financial Statements of the Consumer Goods Industry listed on Bursa Efek IndonesiaIn 2014-2019. The phenomenon occurs is the consumer goods industry experiences fluctuating amount of net profit so Return On Equity (ROE) is the same. Most of the capital cannot meet the amount of debt, which makes the value of Debt to Equity Ratio (DER) high. In addition, companies continue to provide dividends even though experience losses. The purpose of this was to determine effect of ROE and DER on Dividend Payout Ratio (DPR). Using Panel Data Regression Analysis through three approach models, namely common effect, fixed effect and random effect. Chow test, Hausman test and Langrangian multiplier test were carried out to find appropriate approach. The result is that ROE and DER simultaneously have a significant effect on DPR. Furthermore, partially ROE and DER have an effect on DPR.
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Valášek, Jan, and Petr Sváček. "Aeroacoustic computation of fluid-structure interaction problems with low Mach numbers." EPJ Web of Conferences 180 (2018): 02113. http://dx.doi.org/10.1051/epjconf/201818002113.

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This contribution deals with the acoustic simulation of aerodynamical noise generated by a flow over an airfoil or by flow in a flexible channel. Since the considered flow has low Mach number the hybrid approach of acoustic analogies can be applied here with benefits. The fluid-structure-acoustic interaction problem is generally described as a quite complicated problem comprising of three different physical fields - the vibration of the elastic body, the unsteady fluid flow and the acoustics together with mutual couplings. The fluid flow in time dependent domain is governed by the incompressible Navier-Stokes equations in arbitrary Langrangian-Eulerian formulation and the elastic structure is modelled by the means of linear elasticity theory. The Lighthill analogy and acoustic perturbation equation (APE) is considered to describe the sound propagation. The simulation of fluid-structure (FSI) interaction and acoustic field is implemented using the FEM in an in-house solver. The sound sources computed from FSI results are analyzed and within sound propagation simulation the perfectly matched layer technique is used. In the end the results of Lighthill and APE analogy are compared.
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Kreitmayer, Diana, Srikanth R. Gopireddy, Tomomi Matsuura, Yuichi Aki, Yuta Katayama, Taihei Sawada, Hirofumi Kakihara, et al. "Numerical and Experimental Investigation of the Hydrodynamics in the Single-Use Bioreactor Mobius® CellReady 3 L." Bioengineering 9, no. 5 (May 11, 2022): 206. http://dx.doi.org/10.3390/bioengineering9050206.

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Two-way Euler-Lagrange simulations are performed to characterize the hydrodynamics in the single-use bioreactor Mobius® CellReady 3 L. The hydrodynamics in stirred tank bioreactors are frequently modeled with the Euler–Euler approach, which cannot capture the trajectories of single bubbles. The present study employs the two-way coupled Euler–Lagrange approach, which accounts for the individual bubble trajectories through Langrangian equations and considers their impact on the Eulerian liquid phase equations. Hydrodynamic process characteristics that are relevant for cell cultivation including the oxygen mass transfer coefficient, the mixing time, and the hydrodynamic stress are evaluated for different working volumes, sparger types, impeller speeds, and sparging rates. A microporous sparger and an open pipe sparger are considered where bubbles of different sizes are generated, which has a pronounced impact on the bubble dispersion and the volumetric oxygen mass transfer coefficient. It is found that only the microporous sparger provides sufficiently high oxygen transfer to support typical suspended mammalian cell lines. The simulated mixing time and the volumetric oxygen mass transfer coefficient are successfully validated with experimental results. Due to the small reactor size, mixing times are below 25 s across all tested conditions. For the highest sparging rate of 100 mL min−1, the mixing time is found to be two seconds shorter than for a sparging rate of 50 mL min−1, which again, is 0.1 s longer than for a sparging rate of 10 mL min−1 at the same impeller speed of 100 rpm and the working volume of 1.7 L. The hydrodynamic stress in this bioreactor is found to be below critical levels for all investigated impeller speeds of up to 150 rpm, where the maximum levels are found in the region where the bubbles pass behind the impeller blades.
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Hussain, Muzamal, Muhammad Nawaz Naeem, and Mohammad Reza Isvandzibaei. "Effect of Winkler and Pasternak elastic foundation on the vibration of rotating functionally graded material cylindrical shell." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 232, no. 24 (January 22, 2018): 4564–77. http://dx.doi.org/10.1177/0954406217753459.

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In this paper, vibration characteristics of rotating functionally graded cylindrical shell resting on Winkler and Pasternak elastic foundations have been investigated. These shells are fabricated from functionally graded materials. Shell dynamical equations are derived by using the Hamilton variational principle and the Langrangian functional framed from the shell strain and kinetic energy expressions. Elastic foundations, namely Winkler and Pasternak moduli are inducted in the tangential direction of the shell. The rotational motions of the shells are due to the Coriolis and centrifugal acceleration as well as the hoop tension produced in the rotating case. The wave propagation approach in standard eigenvalue form has been employed in order to derive the characteristic frequency equation describing the natural frequencies of vibration in rotating functionally graded cylindrical shell. The complex exponential functions, with the axial modal numbers that depend on the boundary conditions stated at edges of a cylindrical shell, have been used to compute the axial modal dependence. In our new investigation, frequency spectra are obtained for circumferential wave number, length-to-radius ratio, height-to-radius ratio with simply supported–simply supported and clamped–clamped boundary conditions without elastic foundation. Also, the effect of elastic foundation on the rotating cylindrical shells is examined with the simply supported–simply supported edge. To check the validity of the present method, the fundamental natural frequencies of non-rotating isotropic and functionally graded cylindrical shells are compared with the open literature. Also, a comparison is made for infinitely long rotating with the earlier published paper.
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9

Lu, Hongshi, Li Aijun, Wang Changqing, and Zabolotnov Michaelovitch Yuriy. "Impact analysis and adaptive sliding mode control for cislunar payload transportation using spinning tether system." Aircraft Engineering and Aerospace Technology 90, no. 8 (November 5, 2018): 1168–79. http://dx.doi.org/10.1108/aeat-02-2017-0067.

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Purpose This paper aims to present the impact analysis of payload rendezvous with tethered satellite system and the design of an adaptive sliding mode controller which can deal with mass parameter uncertainty of targeted payload, so that the proposed cislunar transportation scheme with spinning tether system could be extended to a wider and more practical range. Design/methodology/approach In this work, dynamical model is first derived based on Langrangian equations to describe the motion of a spinning tether system in an arbitrary Keplerian orbit, which takes the mass of spacecraft, tether and payload into account. Orbital design and optimal open-loop control for the payload tossed by the spinning tether system are then presented. The real payload rendezvous impact around docking point is also analyzed. Based on reference acceleration trajectory given by optimal theories, a sliding mode controller with saturation functions is designed in the close-loop control of payload tossing stage under initial disturbance caused by actual rendezvous error. To alleviate the influence of inaccurate/unknown payload mass parameters, the adaptive law is designed and integrated into sliding mode controller. Finally, the performance of the proposed controller is evaluated using simulations. Simulation results validate that proposed controller is found effective in driving the spinning tether system to carry payload into desired cislunar transfer orbit and in dealing with payload mass parameter uncertainty in a relatively large range. Findings The results show that unideal rendezvous manoeuvres have significant impact on in-plane motion of spinning tether system, and the proposed adaptive sliding mode controller with saturation functions not only guarantees the stability but also provides good performance and robustness against the parameter and unstructured uncertainties. Originality/value This work addresses the analysis of actual impact on spinning tether system motion when payload is docking with system within tolerated docking window, rather than at the particular ideal docking point, and the robust tracking control of deep-space payload tossing missions with the spinning tether system using the adaptive sliding mode controller dealing with parameter uncertainties. This combination has not been proposed before for tracking control of multivariable spinning tether systems.
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10

Schaefli, B., R. J. van der Ent, R. Woods, and H. H. G. Savenije. "An analytical model for soil-atmosphere feedback." Hydrology and Earth System Sciences Discussions 8, no. 5 (September 7, 2011): 8315–54. http://dx.doi.org/10.5194/hessd-8-8315-2011.

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Abstract. Soil-atmosphere feedback is a key for understanding the hydrological cycle and the direction of potential system changes. This paper presents an analytical framework to study the interplay between soil and atmospheric moisture, using as input only the boundary conditions at the upstream end of an atmospheric moisture stream line. The underlying Eulerian-Langrangean approach assumes advective moisture transport with average wind speed along the stream line and vertical moisture exchange with the soil compartment of uniform vertical properties. Precipitation, evaporation from interception and runoff are assumed to depend through simple functional relationships on the soil moisture or the atmospheric moisture. Evaporation from soil moisture (including transpiration) depends on both state variables, which introduces a nonlinear relationship between the two compartments. This nonlinear relationship can explain some apparently paradoxical phenomena such as a local decrease of precipitation accompanied by a runoff increase. The solutions of the resulting water balance equations correspond to two different moisture regimes along a stream line, either monotonically increasing or decreasing when traveling inland, depending on boundary conditions and parameters. The paper discusses how different model parameters (e.g. time scales of precipitation, evaporation or runoff) influence these regimes and how they can create regime switches. Such an analysis has potential to anticipate the range of possible land use and climate changes or to interpret the results of complex land-atmosphere interaction models. Based on derived analytical expressions for the Horton index, the Budyko curve and a precipitation recycling ratio, the analytical framework opens new perspectives for the classification of hydrological systems.
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Дисертації з теми "Langrangian approach"

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Hawkins, Jeffrey Thomas 1977. "A Langrangian decomposition approach to weakly coupled dynamic optimization problems and its applications." Thesis, Massachusetts Institute of Technology, 2003. http://hdl.handle.net/1721.1/29599.

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Анотація:
Thesis (Ph. D.)--Massachusetts Institute of Technology, Sloan School of Management, Operations Research Center, 2003.
Includes bibliographical references (p. 187-192).
We present a Lagrangian based approach to decoupling weakly coupled dynamic optimization problems for both finite and infinite horizon problems. The main contributions of this dissertation are: (i) We develop methods for obtaining bounds on the optimal cost based on solving low dimensional dynamic programs; (ii) We utilize the resulting low dimensional dynamic programs and combine them using integer programming methods to find feasible policies for the overall problem; (iii) To illustrate the power of our methods we apply them to a large collection of dynamic optimization problems: multiarmed bandits, restless bandits, queueing networks, serial supply chains, linear control problems and on-line auctions, all with promising results. In particular, the resulting policies appear to be near optimal. (iv) We provide an indepth analysis of several aspects of on-line auctions, both from a buyer's and a seller's perspective. Specifically, for buyers we construct a model of on-line auctions using publicly available data and develop an algorithm for optimally bidding in multiple simultaneous auctions. For sellers we construct a model of on-line auctions using publicly available data and demonstrate how a seller can increase the final selling price using dynamic programming.
by Jeffrey Thomas Hawkins.
Ph.D.
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2

Taffoni, Giuliano. "Formation and Evolution of Dark Matter Haloes in Hierarchical Models for Structure Formation." Doctoral thesis, SISSA, 2002. http://hdl.handle.net/20.500.11767/4286.

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The layout of this thesis is the following. In Chapter 2, I introduce some basic elements of modem cosmology and devote special attention to recent observational constraints on cosmological parameters. I also review the theory of gravitational instability, paying particular attention to the theory of collapse of the initial density perturbations. Chapter 3 deals with the issue of hierarchical clustering. I present a Monte Carlo code to generate catalogues of haloes based on the EPS formalism, and then compare its results with numerical simulations. In Chapters 4, 5, and 6 PINOCCHIO code is presented and tested. First, I describe the analytical backbones of this algorithm and then test the code against numerical simulations in order to verify its ability of estimating the statistical properties of the hierarchical clustering of haloes. I will show that PINOCCHIO can also reproduce the numerical experiments to an object-by-object level. In the last two Chapters, I study the evolution of satellites in DM haloes. Chapter 7 derives a simple formula for the decaying time of rigid satellites orbiting in Navarro Frank & White haloes, while Chapter 8 studies the fate of mass loosing satellites which sink in the main DM halo. Conclusions are presented in the last sections of the chapters containing original results (namely, Chapter 3,4,5,6,7,8) and summarized in Chapter 9.
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Fugleberg, Todd Darwin. "Vacuum structure of QCD in an effective Langrangian approach." Thesis, 2000. http://hdl.handle.net/2429/11141.

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The vacuum structure of QCD is studied using an anomalous effective Lagrangian approach. This approach makes it possible to determine how physical observables depend on the strong CP violation parameter, θ. The θ -dependence of QCD and the phenomenology of the light pseudoscalar mesons in this theory are illustrated. The vacuum structure of QCD is shown to be quite complex with the prediction of a number of different types of nontrivial vacuum states. Two specific examples of nontrivial vacuum states are analysed in more detail. The decay rate of a metastable vacuum state for the θ = 0 case is nonperturbatively calculated in both the zero and high temperature limits. The formation of a nontrivial vacuum state in heavy ion collisions is predicted in a simplified numerical model. These results have implications for the study of the evolution of the early universe near the QCD phase transition and may be tested experimentally very soon in heavy ion collision experiments.
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Частини книг з теми "Langrangian approach"

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Widyadanaa, Gede Agus, and Hui Ming Wee. "A Multi-Product EPQ Model with Discrete Delivery Order: A Langrangean Solution Approach." In Global Perspective for Competitive Enterprise, Economy and Ecology, 601–8. London: Springer London, 2009. http://dx.doi.org/10.1007/978-1-84882-762-2_57.

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Тези доповідей конференцій з теми "Langrangian approach"

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Singh, Rajiv Kumar, Jitendra Shukla, Aishwarya Chandel, and Harshit Singh. "Electron Bunching and Power Growth in a Gyro-TWT Amplifier: A Langrangian Approach." In 2020 IEEE International Conference on Computing, Power and Communication Technologies (GUCON). IEEE, 2020. http://dx.doi.org/10.1109/gucon48875.2020.9231068.

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2

Abid, Muhammad, and Adnan Aslam Noon. "Turbulent Flow Simulations Through Tarbela Dam Tunnels Considering the Effect of Sediment Particles." In ASME 2010 10th Biennial Conference on Engineering Systems Design and Analysis. ASMEDC, 2010. http://dx.doi.org/10.1115/esda2010-24201.

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The sediments inflow in the Tarbela reservoir is resulting in reduction in water storage capacity and damage to the tunnels carrying water to the power generating units and ultimately to the plant equipment. The turbulent flow in tunnel-2 of the Tarbela Dam Project (TDP) is analyzed for the sediment particles tracking in ANSYS CFX. The particles flow in the tunnel is considered random and striking the tunnel walls at different impact angles. Langrangian particles tracking approach is used for the particles deposition, which is a oneway coupling phenomena as the carrier phase is unaffected by the sediment particles because of particle mass loadings less than 0.2 and unaltered flow field. Reynolds Stress Model (RSM) is used for turbulent modeling as it takes care of anisotropic effects near the tunnel walls and is used in flows with strong curvature, swirling flows, flows with strong acceleration/retardation.
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3

Gupta, Amit, and J. T. Kshirsagar. "Numerical Experiments on Solid Handling Pump." In ASME 2006 2nd Joint U.S.-European Fluids Engineering Summer Meeting Collocated With the 14th International Conference on Nuclear Engineering. ASMEDC, 2006. http://dx.doi.org/10.1115/fedsm2006-98004.

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Solid handling pumps are used in managing sewage and other solid materials that could flow along with the water or any other fluid. The design of solid handling pump components is also deviating significantly from clear water pump components. The flow passages need to be maintained to allow solid particles of specified sizes smoothly without any obstruction. This aspect of different design from conventional design causes performance deterioration of the pump. The laboratory testing of the solid handling pumps is normally carried out with clear water and a judgment is used based on experience about the deterioration in performance caused by solid particles (size and number of particles). The actual performance measurement with varying particle sizes and its cluster density is very rarely available. A case of solid handling pump is taken up for detail investigation using numerical approach. The preliminary analysis has been carried out with solid handling impeller with clear water as medium of flow. The solid particles are then injected with different sizes and number of solid. Both Eulerian and Langrangian multiphase flow (MPF) approach have been used to study the hydraulic performance deterioration and particle trajectory in the working pump. The paper describes the approaches used and discusses the results considering generally accepted behavior of solid handing pumps.
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4

Hong, Chungpyo, Yutaka Asako, and Koichi Suzuki. "Performance of Parallel-Flow Gas-to-Gas Micro-Double-Tubes-Heat Exchangers." In ASME 2009 International Mechanical Engineering Congress and Exposition. ASMEDC, 2009. http://dx.doi.org/10.1115/imece2009-12430.

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Heat transfer performance of two-stream parallel-flow gas-to-gas micro-double-tubes-heat exchangers was investigated numerically. The flow passages of the micro- double-tubes-heat exchanger are a circular tube for hot passage and a concentric annular tube for cold passage. A circular tube of r = 50 μm and a concentric annular tube of ri = 51 μm and ro = 71 μm with an identical cross-sectional area were chosen and the selected length was 20mm, respectively. Then, the partition wall is assumed to be a stainless steel tube with 1 μm in thickness. Numerical methodology is based on the arbitrary-Langrangian-Eulerian method. Computations were performed for wide flow range to find the effects of capacity ratio on the heat transfer characteristics of gas-to-gas micro-double-tubes-heat exchangers. The results are presented in form of temperature contours, bulk temperature, total temperatures and heat flux variation along the length. Also, the effectiveness and the number of transfer units approach and the estimation of the heat exchange rate were discussed.
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5

Croce, Giulio, Paola D’Agaro, and Nicola Suzzi. "Optimization of Hybrid Hydrophilic-Hydrophobic Surfaces for Dropwise Condensation Enhancement." In ASME 2019 17th International Conference on Nanochannels, Microchannels, and Minichannels. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/icnmm2019-4291.

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Abstract A langrangian-based phenomenological model, following the evolution of the individual droplets nucleating at random positions, is applied to the simulation and optimization of hybrid, mixed hydrophobic and hydrophilic surfaces. The proposed mathematical model was originally developed to simulate droplets pattern evolution in the framework of in-flight icing problems and takes into account the surface tension effects (via the advancing and receding contact angle values), the external force balance on the single droplets, as well as the both the condensing and coalescence process. Here, the model is extended to the case of an arbitrary curved substrate surface and a parametric analysis of different cases is carried out, looking for the parameters that help to identify the optimal design for a given set of wettability properties, nucleation site density and wet surface condensation rates. A discussion on the sensitivity of the solutions with respect to the expected high uncertainties on the estimate of some of these parameters in actual practical problems is also presented, in order to assess the effectiveness of the simulation as a design tool. The analysis is carried out for condensation enhancement on both plane surfaces and mini or micro tubes. Comparison with experimental, open literature data ensure the reliability of the approach for both geometries.
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Yi, Jiang Tao, Fook Hou Lee, Siang Huat Goh, Yu Ping Li, and Xi Ying Zhang. "Effective-Stress Finite Element Analysis of Spudcan Penetration." In ASME 2012 31st International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/omae2012-83138.

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The numerical modeling of spudcan penetration involves technical challenges posed by large soil deformation coupled with significant material non-linearity. The Lagrangian approach commonly used for solid stress analysis often does not work well with large deformations, resulting in premature termination of the analysis. Recently, the Arbitrary Langrangian Eulerian (ALE) and the Eulerian methods have been used in spudcan analysis to overcome problems caused by the soil flow and large deformation. However, most of the reported studies are based on total stress analysis and therefore shed no light on the excess pore pressures generated during spudcan installation. As a result, much remains unknown about the long-term behaviour of spudcans in the ground, which is affected by the dissipation of excess pore pressures. This paper reports an effective-stress finite element analysis of spudcan installation in an over-consolidated (OC) soft clay. The Eulerian analysis was conducted using ABAQUS/ Explicit, with the effective stress constitutive models coded via the material subroutine VUMAT. The results demonstrated the feasibility of conducting effective-stress finite element analysis for undrained spudcan penetration in OC clays. The paper discusses the flow mechanism, stable cavity depths and bearing capacity factors when spudcan installation occurs in various OC soils. It was found that the pore pressure build-up concentrates in a bulb-shaped zone surrounding the spudcan. The size of the pore pressure bulb increases with increasing penetration. The maximum excess pore pressure, which is generated near the spudcan tip, is predominantly controlled by the undrained shear strength at the tip level.
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7

Pike, Kenton, Gang Duan, Jason Sun, and Paul Jukes. "Comprehensive FEA of Thermal Mitigation Buoyancy Module (TMBM)–Soil Interaction Using the Coupled Eulerian–Lagrangian (CEL) Method." In ASME 2010 29th International Conference on Ocean, Offshore and Arctic Engineering. ASMEDC, 2010. http://dx.doi.org/10.1115/omae2010-20885.

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Thermal expansion and global buckling is a critical design aspect for subsea flowline systems subjected to high pressure and high temperature (HPHT). In the Gulf of Mexico, HPHT oil/gas production is becoming exceedingly common as drilling and production depths extend deeper. Advanced finite element analysis becomes essential for flowline expansion and buckling design which is highly dependent on pipe-soil interaction behavior. For decades, pipe-soil interaction has been the focus of many research studies and joint industry projects. For HPHT flowline systems, thermal mitigation is decisive for safe design. Thermal mitigation acts to control global buckling at designate locations and avoid buckling in unknown locations. Thermal mitigation results in significant cost savings by lowering the welding class besides the buckling locations and increases safety in terms of local buckling, fracture, and fatigue. One widely used thermal mitigation method involves attaching a buoyancy module around a segment of the flowline. In this paper the Coupled Eulerian Langrangian (CEL) finite element (FE) formulation is utilized to simulate the interaction between soil and the thermal mitigation buoyancy module (TMBM). The paper demonstrates the capability of the CEL FE method to simulate large soil deformation without the numerical difficulties that are commonly associated with other numerical formulations e.g. ALE (Arbitrary Lagrangian Eulerian) or more conventional Lagrangian. Initially, a three dimensional (3D), continuum, FE model is used to establish the variation of initial embedment along the length of the buoyancy and adjoining pipe. The study then establishes the lateral displacement/resistance relationships under different levels of contact pressure and soil embedment for a series of buoyancy-soil interaction segments, also using the CEL FE method. Current practice for global pipeline thermal expansion FEA is to utilize the same friction model for both buoyancy-soil interaction and pipe-soil interaction. The obtained buoyancy-soil interaction model from the current study is to be used as input to the global FE model to more precisely simulate flowline lateral buckling behavior. This paper presents a practical application of the current state of the art in modeling large soil deformations in providing an improved approach for modeling buoyancy-soil interactions in the global FEA of pipeline thermal expansion and lateral buckling.
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Звіти організацій з теми "Langrangian approach"

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Shashkov, Mikhail, Edward Love, and Guglielmo Scovazzi. A multi-scale Q1/P0 approach to langrangian shock hydrodynamics. Office of Scientific and Technical Information (OSTI), March 2006. http://dx.doi.org/10.2172/902215.

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2

Tremblay, Bruno. Forecasting Future Sea Ice Conditions in the MIZ: A Langrangian Approach. Fort Belvoir, VA: Defense Technical Information Center, September 2012. http://dx.doi.org/10.21236/ada572580.

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