Relevant bibliographies by topics / Piping system modeling

Contents

  1. Journal articles
  2. Dissertations / Theses
  3. Books
  4. Book chapters
  5. Conference papers

Academic literature on the topic 'Piping system modeling'

Author: Grafiati
Published: 4 June 2021
Last updated: 5 February 2022

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Piping system modeling.'

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 "Piping system modeling"

1

Kawashima, K., S. Yamanishi, S. Kanai, and H. Date. "Finding the next-best scanner position for as-built modeling of piping systems." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XL-5 (June 6, 2014): 313–20. http://dx.doi.org/10.5194/isprsarchives-xl-5-313-2014.

Full text
Abstract:
Renovation of plant equipment of petroleum refineries or chemical factories have recently been frequent, and the demand for 3D asbuilt modelling of piping systems is increasing rapidly. Terrestrial laser scanners are used very often in the measurement for as-built modelling. However, the tangled structures of the piping systems results in complex occluded areas, and these areas must be captured from different scanner positions. For efficient and exhaustive measurement of the piping system, the scanner should be placed at optimum positions where the occluded parts of the piping system are captured as much as possible in less scans. However, this "nextbest" scanner positions are usually determined by experienced operators, and there is no guarantee that these positions fulfil the optimum condition. Therefore, this paper proposes a computer-aided method of the optimal sequential view planning for object recognition in plant piping systems using a terrestrial laser scanner. In the method, a sequence of next-best positions of a terrestrial laser scanner specialized for as-built modelling of piping systems can be found without any a priori information of piping objects. Different from the conventional approaches for the next-best-view (NBV) problem, in the proposed method, piping objects in the measured point clouds are recognized right after an every scan, local occluded spaces occupied by the unseen piping systems are then estimated, and the best scanner position can be found so as to minimize these local occluded spaces. The simulation results show that our proposed method outperforms a conventional approach in recognition accuracy, efficiency and computational time.
APA, Harvard, Vancouver, ISO, and other styles
2

Choi, Ho-Sung, Jung-Hwan Moon, and Jae-Ou Lee. "Fluid Behavior Modeling Optimal Design Using Network Piping Analysis Method." Fire Science and Engineering 35, no. 1 (2021): 93–99. http://dx.doi.org/10.7731/kifse.6af732a2.

Full text
Abstract:
The piping design should be considered by way of the network system in order to supply water for reliable fire extinguishing. However, the pipe scheduling method in line by the National Fire Safety Code is typically applied. When the modeling analysis method of fluid behavior is utilized based on the piping network theory, the fire-extinguishing water can be supplied more stably in a large-scale plant. Because a piping network consists of a large number of node points as well as consumes a lot of time and effort, it is recommended to use the commercial analysis program according to international standards. In this study, we used a piping network analysis program, sisHYD, which can model the actual piping according to the coordinates and analyze the fluid behavior inside the piping. As a result of the piping network analysis, it was possible to reduce the diameter of piping while ensuring the supply stability of firefighting water compared to the pipe scheduling method. Consequently, the value engineering effect of a construction project can be enhanced by reducing the wasted budget and inefficient factors.
APA, Harvard, Vancouver, ISO, and other styles
3

Soroushian, Siavash, Arash E. Zaghi, Manos Maragakis, Alicia Echevarria, Yuan Tian, and Andre Filiatrault. "Analytical Seismic Fragility Analyses of Fire Sprinkler Piping Systems with Threaded Joints." Earthquake Spectra 31, no. 2 (2015): 1125–55. http://dx.doi.org/10.1193/083112eqs277m.

Full text
Abstract:
For the first time, an analytical modeling methodology is developed for fire sprinkler piping systems and used to generate seismic fragility parameters of these systems. The analytical model accounts for inelastic behavior constituents of the system, including: threaded joints, solid braces, hangers, and restrainers. The model incorporates a newly developed hysteresis model for threaded tee joints that is validated by the experimental results of several tee subassemblies. The modeling technique at the subsystem level is validated by using the experimental results of a sprinkler piping system. The methodology is used to obtain the seismic response of the fire sprinkler piping system of University of California, San Francisco Hospital under a suite of 96 artificially generated triaxial floor acceleration histories. After the component fragility parameters are obtained for the components of the system, three system-level damage states are defined, and a joint probabilistic seismic demand model is utilized to develop system fragility parameters.
APA, Harvard, Vancouver, ISO, and other styles
4

Quin˜ones, D. F., R. E. Nickell, and D. M. Norris. "Static and Dynamic Analysis of Flaw Stability in Piping Systems." Journal of Pressure Vessel Technology 112, no. 3 (1990): 204–12. http://dx.doi.org/10.1115/1.2928615.

Full text
Abstract:
Static and dynamic pretest simulations of a degraded nuclear piping test are performed to investigate crack stability and piping integrity. The purpose of this study is to provide system design guidance for a large-diameter piping test and to gain insight on modeling dynamic crack behavior in austenitic and carbon steel base metal and weldments. Combined operating temperature and pressure plus an idealized seismic loading are applied until substantial crack growth, leakage, or pipe guillotining is predicted. The importance of modeling elbow deformation and plasticity is demonstrated.
APA, Harvard, Vancouver, ISO, and other styles
5

Skormin, V. "A Frequency Approach to Mathematical Modeling of a Nuclear Power Plant Piping System." Journal of Vibration and Acoustics 107, no. 1 (1985): 106–11. http://dx.doi.org/10.1115/1.3274699.

Full text
Abstract:
A methodology is presented for identification of a nuclear power plant piping system, which employs mathematical description in the form of transfer function matrix, frequency domain technique for estimation of system dynamic parameters, statistical technique for verification of model configuration and evaluation of parameter estimates, adaptive approach for current model updating. Model applications for estimation and monitoring of forcing functions, displacements, and stresses due to transient processes and steady state vibrations in the piping system are proposed. Methodology is illustrated by numerical examples.
APA, Harvard, Vancouver, ISO, and other styles
6

Kawashima, Kazuaki, Satoshi Kanai, and Hiroaki Date. "As-built modeling of piping system from terrestrial laser-scanned point clouds using normal-based region growing." Journal of Computational Design and Engineering 1, no. 1 (2014): 13–26. http://dx.doi.org/10.7315/jcde.2014.002.

Full text
Abstract:
Abstract Recently, renovations of plant equipment have been more frequent because of the shortened lifespans of the products, and as-built models from large-scale laser-scamied data is expected to streamline rebuilding processes. However, the laser-scanned data of an existing plant has an enormous amount ofpoints, captures inmcate objects, and includes a high noise level, so the manual reconstmction of a 3D model is very time-consuming and costly. Among plant equipment, piping systems account for the greatest proportion. Therefore, the purpose of this research was to propose an algorithm which could automatically recognize a piping system from the terrestrial laser- scanned data plant equipment. The straight pomon pipes, connecting parts, and connection relationship ofthe piping system can be recognized in this algorithm. Normal-based region growing and cylinder surface fitting can extract all possible locations ofpipes, including straight pipes, elbows, and junctions. Tracing the axes of a piping system enables the recognition of the positions of these elements and their connection relationship. Using only point clouds, the recognition algorithm can be performed in a fUlly automatic way. The algorithm was applied to large-scale scamied data of an oil rig and a chemical plant. Recognition rates of about 86%, 88%, and 71% were achieved straight pipes, elbows, andjunctions, respectively.
APA, Harvard, Vancouver, ISO, and other styles
7

Tsukimori, Kazuyuki. "Theoretical Modeling of Creep Behavior of Bellows and Some Applications." Journal of Pressure Vessel Technology 123, no. 2 (2000): 179–90. http://dx.doi.org/10.1115/1.1320817.

Full text
Abstract:
The use of bellows expansion joints is an effective method to rationalize various piping systems in industry. In the structural design, the requirements for preventing failures such as ratcheting, fatigue, and buckling should be satisfied. The mechanisms of some failure modes of bellows are different from those of vessels and piping components, which makes it difficult to estimate the behaviors. In the case of high-temperature operation, creep behavior of bellows should be considered. In this paper, a simplified theoretical modeling of creep behavior of bellows is presented. The formulation is developed by using Norton’s law for creep property of bellows material and assuming meridional bending stress is dominant. According to this modeling, bellows convolution dimensions are considered directly. The excessive creep deformation problem of bellows under internal pressure and the elastic follow-up behavior problem of a piping system with bellows expansion joints are examined as the applications of this modeling. The results are compared with detailed analysis results by FEM, and the applicability and the validity of this modeling is discussed.
APA, Harvard, Vancouver, ISO, and other styles
8

Van Blaricum, Vicki L., and Vincent F. Hock. "Water Distribution System Modeling and Remote Monitoring." Advanced Materials Research 38 (March 2008): 132–42. http://dx.doi.org/10.4028/www.scientific.net/amr.38.132.

Full text
Abstract:
Localized internal corrosion of water distribution piping is difficult to detect, diagnose, and mitigate. This paper describes the demonstration and validation of multi-parameter water quality sensors and corrosion rate sensors that were permanently installed at a U. S. Army installation to detect corrosion problems and fine-tune the chemical treatment program. This paper will include results of the sensor demonstration and validation. Follow-on work includes the integration of the sensors with a dynamic real-time water distribution system chemical and hydraulic simulation. This work will also be described.
APA, Harvard, Vancouver, ISO, and other styles
9

Hwang, Se-Yun, Min-Seok Kim, and Jang-Hyun Lee. "Thermal Stress Analysis of Process Piping System Installed on LNG Vessel Subject to Hull Design Loads." Journal of Marine Science and Engineering 8, no. 11 (2020): 926. http://dx.doi.org/10.3390/jmse8110926.

Full text
Abstract:
In this paper, the procedure for the strength evaluation of the piping system installed on liquefied natural gas (LNG) carriers is discussed. A procedure that accounts for the ship’s wave load and hull motion acceleration (as well as the deformation due to the thermal expansion and contraction experienced by the hull during seafaring operations) is presented. The load due to the temperature and self-weight of the piping installed on the deck is also considered. Various operating and load conditions of the LNG piping system are analyzed. Stress analysis is performed by combining various conditions of sustained, occasional, and expansion loads. Stress is assessed using finite element analysis based on beam elements that represent the behavior of the piping. The attributes of the piping system components (such as valves, expansion joints, and supports) are represented in the finite element model while CAESAR-II, a commercial software is used for finite element analysis. Component modeling, load assignment, and load combinations are presented to evaluate pipe stresses under various load conditions. An evaluation model is selected for the piping arrangement of LNG and the evaluated stress is compared with the allowable stress defined by the American Society of Mechanical Engineers (ASME).
APA, Harvard, Vancouver, ISO, and other styles
10

Fascetti, Alessandro, and Caglar Oskay. "Multiscale modeling of backward erosion piping in flood protection system infrastructure." Computer-Aided Civil and Infrastructure Engineering 34, no. 12 (2019): 1071–86. http://dx.doi.org/10.1111/mice.12489.

Full text
APA, Harvard, Vancouver, ISO, and other styles

Dissertations / Theses on the topic "Piping system modeling"

1

Kendrick, Clint Edward. "Development of model for large-bore engine cooling systems." Thesis, Kansas State University, 2011. http://hdl.handle.net/2097/8721.

Full text
Abstract:
Master of Science<br>Department of Mechanical and Nuclear Engineering<br>Kirby S. Chapman<br>The purpose of this thesis is to present on the development and results of the cooling system logic tree and model developed as part of the Pipeline Research Council International, Inc (PRCI) funded project at the Kansas State National Gas Machinery Laboratory. PRCI noticed that many of the legacy engines utilized in the natural gas transmission industry were plagued by cooling system problems. As such, a need existed to better understand the heat transfer mechanisms from the combusting gases to the cooling water, and then from the cooling water to the environment. To meet this need, a logic tree was developed to provide guidance on how to balance and identify problems within the cooling system and schedule appropriate maintenance. Utilizing information taken from OEM operating guides, a cooling system model was developed to supplement the logic tree in providing further guidance and understanding of cooling system operation. The cooling system model calculates the heat loads experienced within the engine cooling system, the pressures within the system, and the temperatures exiting the cooling equipment. The cooling system engineering model was developed based upon the fluid dynamics, thermodynamics, and heat transfer experienced by the coolant within the system. The inputs of the model are familiar to the operating companies and include the characteristics of the engine and coolant piping system, coolant chemistry, and engine oil system characteristics. Included in the model are the various components that collectively comprise the engine cooling system, including the water cooling pump, aftercooler, surge tank, fin-fan units, and oil cooler. The results of the Excel-based model were then compared to available field data to determine the validity of the model. The cooling system model was then used to conduct a parametric investigation of various operating conditions including part vs. full load and engine speed, turbocharger performance, and changes in ambient conditions. The results of this parametric investigation are summarized as charts and tables that are presented as part of this thesis.
APA, Harvard, Vancouver, ISO, and other styles

Books on the topic "Piping system modeling"

1

Saxon, J. B. Modeling dynamically coupled fluid-duct systems with finite line elements. National Aeronautics and Space Administration, 1994.

Find full text
APA, Harvard, Vancouver, ISO, and other styles

Book chapters on the topic "Piping system modeling"

1

Guidara, Mohamed Amine, Lamjed Hadj Taieb, and Ezzeddine Hadj Taïeb. "Determination of Natural Frequencies in Piping Systems Using Transfer Matrix Method." In Design and Modeling of Mechanical Systems - II. Springer International Publishing, 2015. http://dx.doi.org/10.1007/978-3-319-17527-0_76.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Ahmed, S. F., M. M. K. Khan, M. T. O. Amanullah, M. G. Rasul, and N. M. S. Hassan. "Performance Evaluation of Hybrid Earth Pipe Cooling with Horizontal Piping System." In Thermofluid Modeling for Energy Efficiency Applications. Elsevier, 2016. http://dx.doi.org/10.1016/b978-0-12-802397-6.00001-4.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Parisher, Roy A., and Robert A. Rhea. "Three— Dimensional Modeling of Piping Systems." In Pipe Drafting and Design. Elsevier, 2002. http://dx.doi.org/10.1016/b978-075067439-3/50043-5.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

S., Sumesh, A. R. Veerappan, and S. Shanmugam. "Finite Element Analysis of Pipe Bends under External Loads." In Modeling and Simulation Techniques in Structural Engineering. IGI Global, 2017. http://dx.doi.org/10.4018/978-1-5225-0588-4.ch007.

Full text
Abstract:
Pipelines are being used to convey different sorts of fluids from hazardous and toxic substances to high pressure steam. Piping systems are subjected to various external loads leading to major failures with gross plastic deformation. Pipe bends are incorporated into piping systems not only to change the direction of flow but also to provide flexibility, hence they are considered to be critical components and its safe design under various loads becomes important. Earlier studies of pipe bends utilized analytical methods to determine the plastic loads. The evolution of FEM and the advancements in computational capabilities have enabled analysts to generate large number of data which is expensive and time consuming with experimental investigations. In this chapter, the major studies on pipe bends by various researchers are explored. Different studies on pipe bends namely stress analysis and the influence of geometric shape imperfections are also presented.
APA, Harvard, Vancouver, ISO, and other styles

Conference papers on the topic "Piping system modeling"

1

GAO, HUIXING. "A PIPING MODELING AND CALCULATION SYSTEM." In Proceedings of the International Conference on Scientific and Engineering Computation (IC-SEC) 2002. PUBLISHED BY IMPERIAL COLLEGE PRESS AND DISTRIBUTED BY WORLD SCIENTIFIC PUBLISHING CO., 2002. http://dx.doi.org/10.1142/9781860949524_0114.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Jansson, Lennart G., and Lingfu Zeng. "On Modeling Piping Supports in Dynamic Analysis of Nuclear-Power Piping Systems." In 16th International Conference on Nuclear Engineering. ASMEDC, 2008. http://dx.doi.org/10.1115/icone16-48912.

Full text
Abstract:
Piping analysis and its corresponding design evaluation according to ASME are complicated and tedious. One typical reason is the modeling of supports and their design evaluation. It is not exaggerated if one claims that this part of the work can consume about 1/3 of the total budgeted costs that are needed for a piping system analysis. The engineering practices of how a support should be modelled in a piping analysis differ between different regions in the world. The difference arises mainly from in what way the following two parts are weighted in a piping analysis: (1) the dynamic interaction effect between supports and piping, and (2) the big safety margin or, in other words, the conservatism, for a piping system which fulfills ASME’s requirements. In this paper a review of these practices will be first given and, thereafter, an analysis of piping-support interaction will be carried out, and finally our suggestions will be given. Some practical examples from recent projects in Nordic countries will be discussed.
APA, Harvard, Vancouver, ISO, and other styles
3

Wen, Kai. "Modeling and Control of Real Flow Calibration System." In ASME 2020 Pressure Vessels & Piping Conference. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/pvp2020-21102.

Full text
Abstract:
Abstract The calibration of large-diameter flow meters is performed in the calibration station where real flow passes through. The typical calibration process is manipulated by human operators, which is time-consuming and easily affected. Since most of the process parameters are detectable, the smart calibration system was aided by the on-line modeling process and consisted of three parts: the digital twin model, the process controller, and the human-machine interface (HMI). The digital twin model was based on the basic partial differential equations of the gas flow in pipelines and was meant for the flow behavior prediction over short periods and provided decision-making assistance for human operators. The verification of the digital model was based on both the historical process data and the real-time process data. The process controller represented the manipulator meant to replace the human operator. The function of the controller included process control and calibration flow point adjustment. The HMI was designed based on the industrial supervisory control and data acquisition (SCADA) system. Since the process control was essential, the scheduling scheme and command sequence feedback to the SCADA system was rechecked by human operators via the HMI. The result of the active control was displayed in the HMI based on the digital twin model. Since smart control was the tendency in the piping system, the automated process verification and control formed the basis of the smart system. By entering the size and range of the flow meters into the HMI, the entire industrial system inside the calibration station was executed automatically.
APA, Harvard, Vancouver, ISO, and other styles
4

Al-Nassar, Y. N. "Finite Element Modeling of Blade-Rotor System in Turbomachinery." In ASME 2003 Pressure Vessels and Piping Conference. ASMEDC, 2003. http://dx.doi.org/10.1115/pvp2003-2179.

Full text
Abstract:
Modal analysis of Blade-Disk system under the effect of bearing flexibility is investigated. The present study has considered soft to hard bearing flexibility. The main objective here is to read from the modal analysis results the frequencies that are carrying out some information on blade vibration. The modal analysis shows that that there are few frequencies that are changing with the change of bearing flexibility. These are shaft mode only, shaft-blade nature, disk mode only, disk-blade nature, and blade mode only. The shaft-blade modes are the ones of concern here.
APA, Harvard, Vancouver, ISO, and other styles
5

Shirai, Eiji, Takanori Yamada, Kazutoyo Ikeda, et al. "Seismic Design Margin of the Piping and Support System: Part 3—Evaluation of Seismic Margin of the Piping System." In ASME 2010 Pressure Vessels and Piping Division/K-PVP Conference. ASMEDC, 2010. http://dx.doi.org/10.1115/pvp2010-25392.

Full text
Abstract:
Seismic safety is one of the major key issues of nuclear power plant safety in Japan. It is demonstrated that nuclear piping possesses large safety margins through the piping and support system test, which consisted of three dimensional piping, supports, U-bolts, and concrete anchorages, using the E-defense vibration table of National Research Institute for Earth Science and Disaster Prevention, Hyogo Earthquake Engineering Research Center, on extremely high seismic excitation level [1,2,3]. In the above test, the non-linear hysteretic behaviors of the support are quite complicated, but the dissipated energies introduce large damping effects on the piping system response. In order to evaluate the inelastic behavior of the support with respect to the whole piping system response, the following simulation methodology for the support re-evaluation is proposed. 1) Non-linear modeling of the support: • Failure mode and failure capacity of each support. • Simplified non-linear modeling of each support. 2) Simulation Analysis of the piping and support system: • Considering the non-linearity both of the supports and elbows in the piping system. 3) Evaluation of seismic margin: • Focused on the failure level for the support system, and the fatigue damage for the strain range of the piping. The limit state analysis of the typical piping system of a nuclear power plant is presented in this paper, and it is demonstrated that these evaluations of the seismic margins would give important insight into the support reinforcement program on the seismic re-evaluation work.
APA, Harvard, Vancouver, ISO, and other styles
6

Miaris, Angelos, Michael Paessler, Ralf Schledjewski, and Peter Mitschang. "Modeling the Impregnation Process of a Siphon Impregnation System During Filament Winding." In ASME 2011 Pressure Vessels and Piping Conference. ASMEDC, 2011. http://dx.doi.org/10.1115/pvp2011-57543.

Full text
Abstract:
Filament winding is a well-established process for the production of high-end fully wrapped composite pressure vessels. This type of tanks can be designed for service pressures that exceed 700 bar and are ideal for storage of gas fuels like compressed hydrogen in automotive and lightweight applications. As the demand for composite pressure vessels increases, lower costs and better product quality become very important. Impregnation is one of the most important steps in the wet winding process. During this step the dry continuous fibers are combined with the liquid matrix in order to create a fully impregnated semi-finished product. The properties of the impregnated roving have a major effect on the laminate quality and the efficient processing of the liquid matrix has a big influence on the manufacturing costs. The present work is related to the development of a new impregnation method for the processing of carbon fiber rovings. The developed impregnation unit (siphon impregnation system) consists of a sinusoidal cavity without any moving parts. This combined with an automated resin mixing-dosing system this allows complete wet-out of the fibers, precise calibration of the resin fraction, and stable processing conditions. The paper focuses on the modeling of the impregnation process inside the siphon unit. Mathematical expressions for the fiber compaction, the gradual increase of the roving tension, the static pressure, the capillarity of the roving, and the fiber permeation are presented, discussed, and experimentally verified. These expressions were implemented in an algorithm which can model the impregnation process by taking input parameters into account like winding speed, resin dosing, viscosity, and roving tex. The model was solved and the processing parameters of winding tension, fiber volume fraction, and impregnation degree have been simulated. An experimental set-up based on a filament winding machine was used for the validation of the model. Trials with different processing parameters and long run tests have been performed. The results proved that the model can accurately simulate the impregnation process. The good impregnation degree of the wound samples confirmed the efficiency of the siphon impregnation unit.
APA, Harvard, Vancouver, ISO, and other styles
7

Brust, Frederick W., R. Iyengar, M. Benson, and Howard Rathbun. "Severe Accident Condition Modeling in PWR Environment: Creep Rupture Modeling." In ASME 2013 Pressure Vessels and Piping Conference. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/pvp2013-98059.

Full text
Abstract:
A problem of interest in the nuclear power industry involves the response of pressurized water reactor (PWR) pressure boundary components under long-term station blackout (SBO) conditions. SBO is a particularly challenging event to nuclear safety, since all alternating current power required for core cooling is lost. If unmitigated, such a scenario will eventually lead to the reactor core being uncovered. Thermal-hydraulic (T-H), computational fluid dynamics, and structural combined creep/plasticity analyses of this scenario have been conducted and are presented here. In this severe accident scenario, high temperatures can occur, and impart this thermal energy to the surrounding structures, including the reactor vessel, nozzles, reactor coolant system (RCS) hot leg piping and S/G tubes. At such high temperatures and pressures, creep rupture of RCS piping and/or steam generator (S/G) tubes becomes possible. The intent of this paper is to present a finite element based analysis model that can be used to evaluate the time to failure of the nozzle-weld-pipe configuration.
APA, Harvard, Vancouver, ISO, and other styles
8

Tsai, C. S., Yung-Chang Lin, and Wei-Chan Tsai. "Mechanical Modeling of Multiple Trench Friction Pendulum System With Multi-Intermediate Sliding Plates." In ASME 2009 Pressure Vessels and Piping Conference. ASMEDC, 2009. http://dx.doi.org/10.1115/pvp2009-77640.

Full text
Abstract:
In order to upgrade the seismic resistibility of structures and enhance the functionality of an isolator, a new sliding type base isolator system called the multiple trench friction pendulum system (MTFPS) with multi-intermediate sliding plates is proposed. The MTFPS isolator is composed of a trench concave surface and numbers of intermediate sliding plates in each of two orthogonal directions. Mathematical formulations have been derived to examine its characteristics of the proposed MTFPS isolator. Based on mathematical formulations, it can be inferred that the natural frequency and damping effect of the MTFPS isolator change continually during earthquakes. Furthermore, results from shaking table tests demonstrate that the proposed isolator provides good protection to structures for preventing damage from strong earthquakes.
APA, Harvard, Vancouver, ISO, and other styles
9

Farrell, Ronald, and L. Ike Ezekoye. "Valve Modeling Methods for Modal Analysis." In ASME 2019 Pressure Vessels & Piping Conference. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/pvp2019-93904.

Full text
Abstract:
Abstract This paper presents several modeling methods for performing a valve assembly modal analysis. It discusses the background of the methods, their strengths and limitations, and then introduces a new approach that can be used in performing valve modal analysis. An early paper presents a classical approach based on a lumped mass model and the Rayleigh energy principal to determine primary mode natural frequencies. A follow up paper reaffirms the classical method and introduces enhancements. A recent paper provides a comparative study of the classical approach, laboratory testing, and solid modeling results using the finite element analysis program ANSYS Mechanical. In this paper, a third approach is presented, which is an extension of the classical method, where 3-D beam-based geometry is defined using the ANSYS SpaceClaim program that is then ported to ANSYS Mechanical. The classical and solid modeling approaches from the previously cited papers are reviewed to highlight the modeling evolution and then the newly developed approach is presented. An example is presented that compares natural frequency results of the new method and the previous methods. The motivation for the new method is to provide better compatibility with 3-D piping system models, which are typically used to study the effect of valve mass and stiffness on system response without the complexity of a solid model or the difficulty of communicating the details of a classical model to the system modeler. Much of the process of creating a 3-D beam model is automated. It uses input from an existing classical model and employs the following ANSYS software packages: SpaceClaim, Workbench, Mechanical, and ACT. A great feature of the resulting 3-D model is that beam geometry is more realistic to scale, and therefore provides valuable user feedback for checking model validity. This approach is an improvement over the classical model where only manual data input validation is possible. Other benefits of the new method are covered in greater detail in the paper.
APA, Harvard, Vancouver, ISO, and other styles
10

Uddin, M. F., F. W. Brust, G. M. Wilkowski, S. Kalyanam, and J. Martin. "Modeling of Pipe System Behavior With Circumferential Surface Crack for Secondary Stress Margin Assessment." In ASME 2017 Pressure Vessels and Piping Conference. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/pvp2017-66037.

Full text
Abstract:
In flaw evaluation criteria, the design limits for the secondary stresses is frequently different than the primary stresses. The evaluation procedure for primary stresses are load-controlled based which is independent of pipe deformation. The evaluation procedures for secondary stresses are displacement controlled which are dependent on pipe deformation. Certain stress components such as thermal expansion, thermal striping, welding residual stress, misalignment/cold-springing, dynamic anchor motion are historically considered secondary stresses and their design limits are based on elastic stress analysis. In reality, there can be much more rotation/displacement of the pipe with nonlinear fracture behavior due to nonlinear material behavior and plasticity at the crack plane providing extra margins on the elastically calculated rotation values that come from uncracked-pipe design analyses. In assessing secondary stress margin, a secondary stress reduction factor is defined as the ratio of elastic-plastic moment to elastic moment. This is equivalent to another concept using a Plastic Reduction Factor (PRF) as well as the inverse of structural (or safety) factor (SF) in ASME Section XI flaw evaluation criteria for various service levels. In this work, the secondary stress reduction factor was determined for a representative pipe system with multiple crack sizes, crack locations, and loading conditions. Nonlinear finite element (FE) analyses of a whole uncracked-pipe system were performed using ABAQUS® under various loading combinations to determine the critical locations for cracks in the pipe system. Next, FE analyses of the cracked-pipe system were carried out using cracked-pipe element — a methodology developed by the authors. Cracked-pipe system analyses were conducted for two loading conditions — one producing contained plasticity or single-hinge system and the other producing larger plasticity in the pipe system. Several analyses were conducted for each loading conditions with a combination of two crack sizes at two key locations. Secondary stress reduction factors were then calculated for both loading conditions in the pipe system. Finally, the margin in secondary stress was assessed for the pipe system by comparing the secondary stress reduction factors with that for straight pipe sections (determined for experimental bend tests) as well as with the recommended equivalent PRF and the equivalent ASME secondary stress correction factors.
APA, Harvard, Vancouver, ISO, and other styles
We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!

To the bibliography