Academic literature on the topic 'Move subroutine'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Move subroutine.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Journal articles on the topic "Move subroutine"
1
Wang, Li Xia, Zhan Rong Feng, and Ran Yang Zhang. "Research on Siemens PLC Pulse Control." Advanced Materials Research 705 (June 2013): 616–20. http://dx.doi.org/10.4028/www.scientific.net/amr.705.616.
Full textAbstract:
In order to apply the PTO pulse function of Siemens PLC in a more systematic, convenient and effective way, this thesis adopts the position control wizard to generate envelop and control subroutine. The thesis also makes detailed descriptions and case discussions on the four subroutines of PTO0_CTRL, PTO0_RUN, PTO0_MAN, PTO0_LDPOS, and the results show that using the position control wizard can not only generate envelop and control subroutine conveniently but also bring convenience to the application of the subroutine. Especially, the parameters of the four subroutines interact both independently and mutually. If we make a deeper research on the parameters, we can master their relations further more and apply them more proficiently.
2
Wang, Li Xia, Zhan Rong Feng, and Ze Min Liu. "Research Based on the Position Control Wizard of S7-200." Advanced Materials Research 717 (July 2013): 603–7. http://dx.doi.org/10.4028/www.scientific.net/amr.717.603.
Full textAbstract:
In order to apply the PTO pulse function of S7-200 PLC in a more systematic, convenient and effective way, this thesis adopts the position control wizard to generate envelop and control subroutine. The thesis also makes detailed descriptions and case discussions on the three subroutines of PTO0_CTRL, PTO0_RUN, PTO0_LDPOS, and the results show that using the position control wizard can not only generate envelop and control subroutine conveniently but also bring convenience to the application of the subroutine. Especially, the parameters of the three subroutines interact both independently and mutually. If we make a deeper research on the parameters, we can master their relations further more and apply them more proficiently.
3
Dragoi, Danut, and Alexandru Dragoi. "Modeling of energy-dispersive X-ray diffraction for high-symmetry crystal orientation." Acta Crystallographica Section A Foundations and Advances 75, no. 1 (January 1, 2019): 63–70. http://dx.doi.org/10.1107/s2053273318013864.
Full textAbstract:
The methods for X-ray crystal orientation are rapidly evolving towards versatility, fewer goniometry measurements, automation, high accuracy and precision. One method that attracts a lot of attention is energy-dispersive X-ray diffraction (EDXRD) which is based on detecting reflections from crystallographic planes in a crystal at fixed angles of a parallel polychromatic X-ray incident beam. In theory, an EDXRD peak can move in a diffraction pattern as a function of a crystallographic plane d-spacing and its orientation relative to a fixed direction in space can change also. This is equivalent to the possibility of measuring the orientation of single crystals. The article provides a modeling for the EDXRD method whose main feature is the nonmoving crystal in the sense of traditional goniometry where the angle measurements of diffracting planes are a must. The article defines the equation of orientation for the method and shows the derivation in great detail. It is shown that the exact solutions of the equations can be obtained using the generalized reduced gradient method, a mathematical subroutine that is implemented in Excel software. The significance and scientific impact of the work are discussed along with the validated tested results.
4
Aveiga, David, and Marcelo L. Ribeiro. "A Delamination Propagation Model for Fiber Reinforced Laminated Composite Materials." Mathematical Problems in Engineering 2018 (June 19, 2018): 1–9. http://dx.doi.org/10.1155/2018/1861268.
Full textAbstract:
The employment of composite materials in the aerospace industry has been gradually considered due to the fundamental lightweight and strength characteristics that this type of materials has. The science material and technological progress reached matched perfectly with the requirements for high-performance materials in aircraft and aerospace structures; thus, the development of primary structure elements applying composite materials became something very convenient. It is extremely important to pay attention to the failure modes that influence composite materials performances, since these failures lead to a loss of stiffness and strength of the laminate. Delamination is a failure mode present in most of the damaged structures and can be ruinous, considering that the evolution of interlaminar defects can carry the structure to a total failure followed by its collapse. The present work aims at the development of a delamination propagation model to estimate a progressive interlaminar delamination failure in laminated composite materials and to allow the prediction of material’s degradation due to delamination phenomenon. Experimental data, available at literature, was considered to determine some model parameters, like the strain energy release rate, using GFRPs laminated composites. This new delamination propagation model was implemented as subroutines in FORTRAN language (UMAT-User Material Subroutine) with formulations based on the Fracture Mechanics and Continuum Damage Mechanics. Finally, the UMAT subroutine was complemented with an intralaminar model and compiled beside the commercial Finite Element (FE) software ABAQUS™.
5
Cui, Wei, Yanjun Luo, and Shuang Peng. "Early-Age Cracking Analysis of a HVFA Concrete Structure Based on Thermo-Hygro-Mechanical Modeling Combined with XFEM." Advances in Materials Science and Engineering 2020 (January 8, 2020): 1–13. http://dx.doi.org/10.1155/2020/5793902.
Full textAbstract:
Due to the low hydration rate of high-volume fly ash (HVFA) concrete at early age, the temperature gradient between the concrete core and surfaces could be effectively reduced. However, the low hydration rate results in a lack of hydration degree for early-age HVFA concrete. Thus, during curing, compared to the strength of ordinary Portland cement (OPC), a subsequent lower one of HVFA concrete leads to a more sensitive response to inner stresses induced by thermal and moisture loads. Based on ABAQUS, in this paper, user subroutines in the temperature and moisture fields were developed, with regard to the hydration degree, for simulation of the temperature and moisture influences on concrete. Additionally, the Double Power Law (DPL) model was used to depict early-age deformations of concrete in the mechanical field. Combined with the extended finite element method (XFEM), another subroutine for early-age cracking analysis in the mechanical field was then developed. Together with aforementioned subroutines, a thermo-hygro-mechanical model is derived. For evaluation of early-age cracking initiation and propagation of a pier composed of HVFA concrete, the model was implemented with XFEM. The obtained results show that (1) temperature and restraints are the main causes of cracking; (2) moisture loss affects surface cracks on structures at early age; and (3) although the temperature difference between the core and surfaces is not much obvious due to the reduced rate of heat dissipation from hydration, cracking of early-age HVFA concrete is still likely to happen for its low early strength. Thus, timely curing is critical to prevent early cracking.
6
Muszala, S. P., D. A. Connors, J. J. Hack, and G. Alaghband. "The Promise of Load Balancing the Parameterization of Moist Convection Using a Model Data Load Index." Journal of Atmospheric and Oceanic Technology 23, no. 4 (April 1, 2006): 525–37. http://dx.doi.org/10.1175/jtech1865.1.
Full textAbstract:
Abstract The parameterization of physical processes in atmospheric general circulation models contributes to load imbalances among individual processors of message-passing distributed-multiprocessor systems. Load imbalances increase the overall time to completion of a model run and should be eliminated or reduced as much as possible. Presented herein is a new technique that shows promise for load balancing the parameterization of moist convection found in the Community Climate System Model's (CCSM's) Community Atmosphere Model version 3 (CAM3). At the heart of this technique is a load index that is a marker for moist convection (called a model data load index). The marker for moist convection correlates directly to the amount of processing time per model grid cell and can therefore be used to effect a load balance. Spatial locality on the model grid and temporal locality between model time steps exist that allow a decomposition from a load-balancing step to be retained for multiple time steps. The analysis in this paper shows that the load balance does not need to be applied at every time step and that the number of steps in which the previous load balance remains effective is large enough for the overhead to be cost effective. Tests performed indicate that this technique is scalable to higher-resolution models as well as to higher processor counts than those presented. Through the use of the Load Balancing and Scheduling Framework (LBSF), this technique shows promise in reducing (by ∼47%) the time of the unbalanced load of one particular subroutine in CAM3 at the T85 spectral truncation. A maximum of 3.75 s of total execution time is saved over a 2430-time-step simulation. When extrapolated to a 1000-yr simulation, this translates to a potential savings of ∼22 h in that subroutine alone. Similar methods applied to remaining subroutines can add up to a significant savings. These results are encouraging in that a fine-grained load-balancing technique using the evolving characteristics of geophysical data paves the way for load balancing a broad range of physical calculations, both in CAM3 and other scientific applications, where more general techniques are not practical.
7
Chow, C. L., W. H. Tai, and C. T. Liu. "Prediction of Mixed-mode Fracture in Participate Composite Using a Damage Criterion." Tire Science and Technology 29, no. 2 (April 1, 2001): 79–90. http://dx.doi.org/10.2346/1.2135233.
Full textAbstract:
Abstract In this paper, a damage-coupled Mooney-Rivlin hyperelastic material model and a damage failure criterion are developed based on the theory of damage mechanics. The model is applied to predict the crack initiation angle and fracture load of particulate composite plate under mixed load. The prediction is achieved by implementing the damage model in a finite element package ABAQUS through its user-specified material subroutine. The inclined angles of the pre-crack are θ = 0, 15, 30, 45, 60, and 75°. The predictions are compared with the test results and found to be in satisfactory agreement.
8
Wang, Wenming. "Strain Rate Effect on the Progressive Collapse Analysis of RC Frame Structure under Earthquake." Advances in Civil Engineering 2020 (January 22, 2020): 1–12. http://dx.doi.org/10.1155/2020/5808701.
Full textAbstract:
The strain rate effect can influence the seismic responses of reinforced concrete (RC) structures because the constitutive relationship of concrete and rebar is rate-dependent. This paper carries out progressive collapse analysis to research the influence of strain rate effects on collapse-resistant capacity, collapse mode, and collapse path of the RC frame structure. A progressive collapse simulation program for the reinforced concrete (RC) structure with a static and dynamic constitutive relationship is coded individually using the user subroutine VUMAT and then implemented in the advanced finite element program ABAQUS. The good agreement between experimental and simulation results proves that the coded subroutine is reliable. With the coded subroutine, by conducting progressive collapse analyses of a four-story RC frame structure under earthquake, the effect of strain rate on the response is investigated. The numerical results demonstrate that the collapse-resistant capacity of the structure is underestimated when the strain rate effect is neglected. It is shown that strain rate effects influence the collapse mode and collapse path of the structure. Therefore, strain rate effects should be considered in the progressive collapse analysis of the RC frame structure.
9
Aranda-Ruiz, Josué, and J. A. Loya. "Numerical Analysis of the Brittle-Ductile Transition in the Failure-Mode in Polymeric Materials." Applied Mechanics and Materials 566 (June 2014): 310–15. http://dx.doi.org/10.4028/www.scientific.net/amm.566.310.
Full textAbstract:
In this paper we analyze, using the Finite Element Method, the process of brittle-ductile transition in the failure mode observed in polycarbonate notched specimens under impact loads. In order to analyze this transition we have implemented, through a user subroutine, a damage model which combines a tensional fracture criterion and an energetic, acting simultaneously. The competition between both criteria predicts the difference in material behavior from a critical impact velocity, and how this transition is produced on different planes through the thickness of the specimen. These results show the necessity of employing three-dimensional models for its study.
10
Tuyttens, D. "Some more numerical experiments with LSNNO, a Fortran subroutine for solving large-scale nonlinear network optimization problems." Optimization Methods and Software 3, no. 1-3 (January 1994): 93–110. http://dx.doi.org/10.1080/10556789408805558.
Full textBooks on the topic "Move subroutine"
1
Jourdain, Robert. Turbo Pascal express, revised: 250 ready-to-run assembly language routines that make Turbo Pascal faster, more powerful, and easier to use. 4th ed. New York: A Brady Utility, distributed by Prentice Hall, 1988.
Find full textBook chapters on the topic "Move subroutine"
1
Heucke, Alexa, Georg Peters, and Roger Tagg. "Intelligent Software Agents." In Encyclopedia of Information Science and Technology, First Edition, 1598–602. IGI Global, 2005. http://dx.doi.org/10.4018/978-1-59140-553-5.ch281.
Full textAbstract:
An agent, in traditional use of the word, is a person that acts on behalf of another person or group of persons. In software, the term agent is broadly used to describe software that carries out a specialist range of tasks, on behalf of either a human user or other pieces of software. Such a concept is not new in computing. Similar things have been said about subroutines, re-usable objects, components and Web services. So what makes agents more than just another computer technology buzzword and research fashion?
2
Walker, James C. G. "How to Deal with Several Reservoirs." In Numerical Adventures with Geochemical Cycles. Oxford University Press, 1991. http://dx.doi.org/10.1093/oso/9780195045208.003.0005.
Full textAbstract:
The previous chapter showed how the reverse Euler method can be used to solve numerically an ordinary first-order linear differential equation. Most problems in geochemical dynamics involve systems of coupled equations describing related properties of the environment in a number of different reservoirs. In this chapter I shall show how such coupled systems may be treated. I consider first a steady-state situation that yields a system of coupled linear algebraic equations. Such a system can readily be solved by a method called Gaussian elimination and back substitution. I shall present a subroutine, GAUSS, that implements this method. The more interesting problems tend to be neither steady state nor linear, and the reverse Euler method can be applied to coupled systems of ordinary differential equations. As it happens, the application requires solving a system of linear algebraic equations, and so subroutine GAUSS can be put to work at once to solve a linear system that evolves in time. The solution of nonlinear systems will be taken up in the next chapter. Most simulations of environmental change involve several interacting reservoirs. In this chapter I shall explain how to apply the numerical scheme described in the previous chapter to a system of coupled equations. Figure 3-1, adapted from Broecker and Peng (1982, p. 382), is an example of a coupled system. The figure presents a simple description of the general circulation of the ocean, showing the exchange of water in Sverdrups (1 Sverdrup = 106 m3/sec) among five oceanic reservoirs and also the addition of river water to the surface reservoirs and the removal of an equal volume of water by evaporation. The problem is to calculate the steady-state concentration of dissolved phosphate in the five oceanic reservoirs, assuming that 95 percent of all the phosphate carried into each surface reservoir is consumed by plankton and carried downward in particulate form into the underlying deep reservoir. The remaining 5 percent of the incoming phosphate is carried out of the surface reservoir still in solution.
3
Saigo, Hiroto, and Koji Tsuda. "Graph Mining in Chemoinformatics." In Chemoinformatics and Advanced Machine Learning Perspectives, 95–128. IGI Global, 2011. http://dx.doi.org/10.4018/978-1-61520-911-8.ch006.
Full textAbstract:
In standard QSAR (Quantitative Structure Activity Relationship) approaches, chemical compounds are represented as a set of physicochemical property descriptors, which are then used as numerical features for classification or regression. However, standard descriptors such as structural keys and fingerprints are not comprehensive enough in many cases. Since chemical compounds are naturally represented as attributed graphs, graph mining techniques allow us to create subgraph patterns (i.e., structural motifs) that can be used as additional descriptors. In this chapter, the authors present theoretically motivated QSAR algorithms that can automatically identify informative subgraph patterns. A graph mining subroutine is embedded in the mother algorithm and it is called repeatedly to collect patterns progressively. The authors present three variations that build on support vector machines (SVM), partial least squares regression (PLS) and least angle regression (LARS). In comparison to graph kernels, our methods are more interpretable, thereby allows chemists to identify salient subgraph features to improve the druglikeliness of lead compounds.
4
Ivezi, Željko, Andrew J. Connolly, Jacob T. VanderPlas, Alexander Gray, Željko Ivezi, Andrew J. Connolly, Jacob T. VanderPlas, and Alexander Gray. "Fast Computation on Massive Data Sets." In Statistics, Data Mining, and Machine Learning in Astronomy. Princeton University Press, 2014. http://dx.doi.org/10.23943/princeton/9780691151687.003.0002.
Full textAbstract:
This chapter describes basic concepts and tools for tractably performing the computations described in the rest of this book. The need for fast algorithms for such analysis subroutines is becoming increasingly important as modern data sets are approaching billions of objects. With such data sets, even analysis operations whose computational cost is linearly proportional to the size of the data set present challenges, particularly since statistical analyses are inherently interactive processes, requiring that computations complete within some reasonable human attention span. For more sophisticated machine learning algorithms, the often worse-than-linear runtimes of straightforward implementations become quickly unbearable. The chapter looks at some techniques that can reduce such runtimes in a rigorous manner that does not sacrifice the accuracy of the analysis through unprincipled approximations. This is far more important than simply speeding up calculations: in practice, computational performance and statistical performance can be intimately linked. The ability of a researcher, within his or her effective time budget, to try more powerful models or to search parameter settings for each model in question, leads directly to better fits and predictions.
5
Walker, James C. G. "Interacting Species in Identical Reservoirs." In Numerical Adventures with Geochemical Cycles. Oxford University Press, 1991. http://dx.doi.org/10.1093/oso/9780195045208.003.0010.
Full textAbstract:
In Chapter 7 I showed how much computational effort could be avoided in a system consisting of a chain of identical equations each coupled just to its neighboring equations. Such systems arise in linear diffusion and heat conduction problems. It is possible to save computational effort because the sleq array that describes the system of simultaneous linear algebraic equations that must be solved has elements different from zero on and immediately adjacent to the diagonal only. This general approach works also for one-dimensional diffusion problems involving several interacting species. In such a system the concentration of a particular species in a particular reservoir is coupled to the concentrations of other species in the same reservoir by reactions between species and is coupled also to adjacent reservoirs by transport between reservoirs. If the differential equations that describe such a system are arranged in appropriate order, with the equations for each species in a given reservoir followed by the equations for each species in the next reservoir and so on, the sleq array still will have elements different from zero close to the diagonal only. All the nonzero elements lie no farther from the diagonal than the number of species. More distant elements are zero. Again, much computation can be eliminated by taking advantage of this pattern. I will show how to solve such a system in this chapter, introducing two new solution subroutines, GAUSSND and SLOPERND, to replace GAUSSD and SLOPERD. I shall apply the new method of solution to a problem of early diagenesis in carbonate sediments. I calculate the properties of the pore fluid in the sediment as a function of depth and time. The different reservoirs are successive layers of sediment at increasing depth. The fluid's composition is affected by diffusion between sedimentary layers and between the top layer and the overlying seawater, the oxidation of organic carbon, and the dissolution or precipitation of calcium carbonate. Because I assume that the rate of oxidation of organic carbon decreases exponentially with increasing depth, there must be more chemical activity at shallow depths in the sediment than at great depths.
Conference papers on the topic "Move subroutine"
1
Laino, David J., A. Craig Hansen, and Jeff E. Minnema. "Validation of the AeroDyn Subroutines Using NREL Unsteady Aerodynamics Experiment Data." In ASME 2002 Wind Energy Symposium. ASMEDC, 2002. http://dx.doi.org/10.1115/wind2002-39.
Full textAbstract:
Completion of the full-scale wind tunnel tests of the NREL Unsteady Aerodynamics Experiment (UAE) Phase VI allowed validation of the AeroDyn wind tuxbine aerodynamics software to commence. Detailed knowledge of the inflow to the UAE was the bane of prior attempts to accomplish any in-depth validation in the past. The wind tunnel tests permitted unprecedented control and measurement of inflow to the UAE rotor. The data collected from these UAE tests are currently under investigation as part of an effort to better understand wind turbine rotor aerodynamics in order to improve aero-elastic modeling techniques. Preliminary results from this study using the AeroDyn subroutines are presented, pointing to several avenues toward improvement. Test data indicate that rotational effects cause more static stall delay over a larger portion of the blades than predicted by current methods. Despite the relatively stiff properties of the UAE, vibration modes appear to influence the aerodynamic forces and system loads. AeroDyn adequately predicts dynamic stall hysteresis loops when appropriate steady, 2-D airfoil tables are used. Problems encountered include uncertainties in converting measured inflow angle to angle of attack for the UAE phase VI. Future work is proposed to address this angle of attack problem and to analyze a slightly more complex dynamics model that incorporates some of the structural vibration modes evident in the test data.
2
Yeoh, B. L., S. H. Goh, Y. H. Chan, G. F. You, Y. E. Koh, and Jeffrey Lam. "Optimization of Soft Defect Localization Technique Scan Time Using Dummy Subroutine Test Vector Insertion." In ISTFA 2013. ASM International, 2013. http://dx.doi.org/10.31399/asm.cp.istfa2013p0350.
Full textAbstract:
Abstract Soft Defect Localization (SDL) is a laser scanning methodology that is commonly used to isolate integrated circuits soft defects. The device is exercised by a functional vector set in a loop manner while localized laser heating stimulates a change in the pass/ fail (P/F) response at the location of the defect or critical path. Although SDL is effective for this purpose, long scan time arising from test overheads, can be a concern to turnaround time for root cause understanding. In this paper, an optimized scheme on synchronous SDL that has a potential to eliminate more than 90% of tester overheads and improve overall SDL test time by at least 17% is proposed. This is achieved by optimizing SDL test loop algorithm.
3
Zhao, Aihong, Ian Owens Pericevic, Kennerly Digges, Cing-Dao Kan, Moji Moatamedi, and Jeffrey S. Augenstein. "FE Modeling of the Orthotropic and Three-Layered Human Thoracic Aorta." In ASME 2006 Pressure Vessels and Piping/ICPVT-11 Conference. ASMEDC, 2006. http://dx.doi.org/10.1115/pvp2006-icpvt-11-93573.
Full textAbstract:
The human aorta consists of three layers: intima, media and adventitia from the inner to outer layer. Since aortic rupture of victims in vehicle crashes frequently occurs in the intima and the media, latent aortic injuries are difficult to detect at the crash scene or in the emergency room. It is necessary to develop a multi-layer aorta finite element (FE) model to identify and describe the potential mechanisms of injury in various impact modes. In this paper, a novel three-layer FE aortic model was created to study aortic ruptures under impact loading. The orthotropic material model [1] has been implemented into a user-defined material subroutine in the commercial dynamic finite element software LS-DYNA version 970 [2], which was adopted in the aorta FE model. The Arbitrary-Lagrangian Eulerian (ALE) approach was adopted to simulate the interaction between the fluid (blood) and the structure (aorta). Single element verifications for the user-defined subroutine were performed. The mechanical behaviors of aortic tissues under impact loading were simulated by the aorta FE model. The models successfully predicted the rupture of the layers separately. The results provide a basis for a more in-depth investigation of blunt traumatic aortic rupture (BTAR) in vehicle crashes.
4
Anurag, S., Y. B. Guo, and M. F. Horstemeyer. "The Use of Internal State Variable Plasticity Model via a User Subroutine to Evaluate the Effect of Materials Testing Modes on Hard Machining Simulation." In ASME 2007 International Manufacturing Science and Engineering Conference. ASMEDC, 2007. http://dx.doi.org/10.1115/msec2007-31087.
Full textAbstract:
Hard machining involves large strain, high strain rate, high temperatures, strain rate/temperature coupling, and potential loading history effects. The accuracy of characterizing the dynamic mechanical behavior in hard machining using any constitutive models is strongly affected by materials testing data in which a constitutive model is fitted. Tension or compression tests have been widely used to approximate material properties in various manufacturing processes. However, it has been a critical question whether tension or compression test should be utilized for capturing the true nature of material deformations in a hard machining process. In this study, the influences of two material testing modes on mechanical behavior of AISI52100 steel (62 HRc) were investigated using the internal state variable (ISV) plasticity model. Twenty material constants have been found by nonlinear fitting the ISV plasticity model to the base line test data obtained from each deformation mode. To understand the true nature of hard turning mechanics, a numerical model that incorporate the internal state variable plasticity model via a material user subroutine has been developed with the material constants from the compression and tension tests. A global material failure/damage evolution model was implemented to simulate chip formation which solely depends on the material deformation state. Orthogonal hard turning experiments have been performed to validate the numerical model. It has shown that the material testing modes have profound effects on some materials constants of the ISV model. The stress sensitivity study to ISV model parameters has identified the critical material constants for reflecting the nature of material deformation. The different testing modes have significant influence on the material constants associated with isotropic hardening rather than kinematic hardening. The numerical and experimental results have shown that the material constants from the compression test capture the true nature of a hard machining process. The compression mode of material deformation prevails in hard machining.
5
Akula, Venkata M. K., and Deepak Datye. "Implementation of a Nonlinear Riser-Soil Interaction Model for Abaqus." In ASME 2015 34th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/omae2015-41201.
Full textAbstract:
For a steel catenary riser system, the touch-down point is often a concern as it can influence the structural response of the riser and its performance. Although, riser configurations can be designed to withstand wave loading, internal pressure, external pressure, and thermal loads; the design of risers taking into account the interaction between the riser and the soil, with cycles of contact and separation, still remains challenging. More specifically, when the riser contacts the seabed surface, it penetrates into the soil material. This penetration can cause suction-type behavior when the riser moves away from the surface. Further, it causes permanent deformation in the soil so the riser has to traverse additional distance prior to re-contacting the seabed surface. For formulating a robust riser design using the finite element method, accurate modeling of this nonlinear riser-soil interaction is needed. In the majority of situations, risers are modeled with beam elements. This is an efficient approach considering that a riser-pipeline system can be several thousand meters in length and using shell or brick elements for modeling such a system becomes computationally expensive. In addition, the seabed surface is often modeled as a rigid surface. The riser-soil interaction behavior is then incorporated into the finite element analysis either by defining springs at the contacting nodes or by modifying the normal contact stiffness for the interaction. However, these methods do not entirely capture the nonlinear riser-soil interaction behavior. In this paper, we discuss the modeling of the nonlinear riser-soil interaction through the use of a user subroutine that runs in conjunction with a finite element analysis using Abaqus. This subroutine is intended to provide a special contact interaction property definition between the riser and the seabed. This contact property definition focuses primarily on the normal behavior although frictional resistance is also considered. The results of the simulation and the insights gained are included.
6
Thakkar, Rohan, and Aleksander Czekanski. "A Comparative Finite Element Analysis of Hart-Smith Hyperelastic Model Under Uniaxial, Planar and Equi-Biaxial Tension." In ASME 2017 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/imece2017-72138.
Full textAbstract:
The classical phenomenological compressible Hart-Smith model expressed in exponential-logarithmic terms of stretch invariants is compared with substantial hyperelastic models available in Abaqus. It is implemented in Abaqus Explicit using a customized user subroutine. Compressible Hart-Smith model together with selected acclaimed models available in Abaqus are evaluated under uniaxial tension, equi-biaxial extension and planar tension modes of deformations. The required material constants are determined from a simple uniaxial tension test. In order to investigate mode-independent characteristics of considered models, predictive planar tension and biaxial extension simulations are performed using the material constants derived from a uniaxial tensile test. Obtained numerical results are validated with respect to classical experimental data for natural rubber reported by Treloar.
7
Hartl, Darren, Tyler Zimmerman, Matthew Dilligan, James Mabe, and Frederick Calkins. "Analysis of Shape Memory Alloy Components Using Beam, Shell, and Continuum Finite Elements." In ASME 2010 Conference on Smart Materials, Adaptive Structures and Intelligent Systems. ASMEDC, 2010. http://dx.doi.org/10.1115/smasis2010-3833.
Full textAbstract:
This work discusses the increased capabilities of a three-dimensional analysis tool for shape memory alloy engineering components. As the number and complexity of proposed SMA applications increases, engineers and designers must seek out or develop more capable predictive methods. Three-dimensional models implemented in a continuum finite element analysis (FEA) framework can be applied to most SMA component geometries. However, such methods may require fine meshes in 3-D space, resulting in many degrees of freedom and potentially long analysis times. On the other hand, constitutive models implemented in one dimension can be simple and fast, but are restricted to a limited class of problems for which such reductions are appropriate (e.g., rods and beams). More recently, engineers have begun investigating more complex SMA bending components for which 2-D shell elements might provide a computationally efficient FEA discretization. Here we consider a single modeling tool (a material subroutine) that combines 1-D, 2-D, and 3-D implementations for use in a general FEA framework. As an example analysis case, we consider an SMA bending element that has been adhesively bonded to a carbon fiber-reinforced polymer (CFRP) laminate and is subjected to thermally-induced actuation. The active SMA and passive composite components are bonded in a pre-stressed configuration such that the elastic laminate provides a variable restoring force to the SMA during transformation, resulting in repeatable actuation cycles. This two-part bonded configuration is analyzed using different types of finite elements (1-D beam, 2-D shell, and full 3-D continuum elements). The constitutive behavior of the shape memory alloy is defined using an established three-dimensional model based on continuum thermodynamics and motivated by the methods of classical plasticity. A user material subroutine (UMAT) in an Abaqus Unified FEA framework is used to implement the model. The methodology for capturing 1-D, 2-D, and 3-D thermomechanical response in a single such UMAT is described. The run times of the various analyses are compared, and the relative accuracies of the results are discussed.
8
Collado, F. J., J. M. Marín, and R. Minguijón. "A New Viewfactor Algorithm Specific for Rectangular Enclosures." In ASME 1996 Design Engineering Technical Conferences and Computers in Engineering Conference. American Society of Mechanical Engineers, 1996. http://dx.doi.org/10.1115/96-detc/cie-1331.
Full textAbstract:
Abstract A new viewfactor algorithm valid for any pair of rectangles with all their edges lying parallel to some coordinate axis is presented in this paper. The new procedure is based on the projected contour method, making the best use of the simplicity of this geometry with many engineering applications. The main advantage of the new algorithm compared with other well known procedures, as the Mitalas-Stepheson one, is the great economy of execution time (almost three times faster) without loss of accuracy. Then, for more complicated cases with obstructions solved with clipping methods, where it is necessary to work out a large amount of contour integrals, the potential economy of CPU time is evident. Finally, a FORTRAN 77 subroutine coding the new algorithm is supplied.
9
Zhang, Qian, Yanting Zhang, and Wenchun Jiang. "Model and Experimental Analysis of the Fiber-Reinforced Pultrusion Composite Under Tension and Shear." In ASME 2019 Pressure Vessels & Piping Conference. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/pvp2019-93286.
Full textAbstract:
Abstract This paper proposed a homogenization model, and compiled a VUMAT subroutine to simulate the tension and shear of fiber-reinforced pultrusion composite (FRPC). Experiments were also performed to verify the accuracy of the homogenization model. The results show that, the simulation results agree well with the experiment data. The stiffness and strength increase with the increase of the diameter of the carbon composite part. The limit shear load and the horizontal shear strength decrease with the increase of the span. When FRPC is under shear with smaller span, the matrix tensile damage initiates first and it is the dominate failure mode, then the matrix and fiber compression damage occur at where the indenters contact. However, with the increase of the span, the delamination damage between the wound glass-fiber reinforced composite and pultrusion glass-fiber reinforced composite occurs and becomes the dominate failure mode for FRPC shear.
10
Won, Min-Gu, Jae-Boong Choi, Nam-Su Huh, Hyeong-Yeon Lee, and Woo-Gon Kim. "Finite Element Simulation of Creep Deformation for Gr. 91 Steel at 600 °C Using Garofalo Model." In ASME 2016 Pressure Vessels and Piping Conference. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/pvp2016-63445.
Full textAbstract:
The present paper provides predictive creep deformation model for Gr. 91 steel at 600 °C. To cover primary-secondary creep regions, two types of creep models, i.e. Garofalo’s and RCC-MRx models were considered in the present study, where the parameters of Garofalo’s model were characterized based on experiment results, and the parameters of RCC-MRx model were determined by the values given in the RCC-MRx code. Furthermore, each creep model were developed based on CREEP (user creep subroutine invoked in ABAQUS) codes for applying to finite element (FE) simulations using commercial code. Then, FE analyses for creep deformation were performed by using the developed CREEP codes (for Garofalo’s and RCC-MRx models), and the results were compared with experiment data. As results, Garofalo’s model provides more accurate results than RCC-MRx model.