Journal articles: 'Thick-walled vessel'

1

Parker, A. P., and X. Huang. "Autofrettage and Reautofrettage of a Spherical Pressure Vessel." Journal of Pressure Vessel Technology 129, no. 1 (March 10, 2006): 83–88. http://dx.doi.org/10.1115/1.2389020.

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There is a numerical procedure for modeling autofrettage of thick-walled cylinders that incorporates the Bauschinger effect as a function of prior plastic strain and Von Mises’ yield criterion. In this paper the numerical procedure is extended to solve the analogous problem of a spherical, thick walled steel vessel. An equivalent new analytical solution for the case of a spherical vessel is also formulated. The analytical and numerical solutions are shown to be in close agreement. It is demonstrated numerically that a reautofrettage procedure, previously proposed for cylindrical vessels, may be extremely beneficial for spherical vessels. Additional commentary is provided on the limitations of certain analytic solutions.

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Altenbach, H., GI Lvov, K. Naumenko, and V. Okorokov. "Consideration of damage in the analysis of autofrettage of thick-walled pressure vessels." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 230, no. 20 (August 9, 2016): 3585–93. http://dx.doi.org/10.1177/0954406215615908.

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In this study, the influence of material damage and the Bauschinger effect on the autofrettage of thick-walled pressure vessels is investigated. Constitutive equations for the elasto-plastic deformation and damage processes are presented. Boundary value problems for a thick-walled cylinder and for a thick-walled sphere of constant thickness are formulated. Computations are preformed to find the optimum autofrettage pressure, for which the equivalent stresses in the vessel take the minimum value under process conditions. Furthermore, residual stress fields after the autofrettage are analyzed. The results show that the Bauschinger effect and damage lead to essential reduction of favorable residual stresses.

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Moghadam, J. S. M., Hamid Ekhteraiee Toosi, and S. A. Razavi. "Investigating the Effect of Internal Pressure and Thickness of Thick-Walled Cylindrical Vessels on the Ratcheting Strains under Compressive Cycling Loading Using the Quasi-Creep Method." Mapta Journal of Mechanical and Industrial Engineering (MJMIE) 5, no. 2 (July 22, 2021): 14–22. http://dx.doi.org/10.33544/mjmie.v5i2.173.

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Thick-walled vessels have many applications in military, chemical, and aerospace industries and also in nuclear facilities. Increasing the internal pressure inside these vessels can take some of the layers of the vessel into the plastic zone. If this happens several times, we will see the accumulation of plastic strains called ratcheting. This paper assumes that the thick-walled vessel is subjected to a cyclic internal pressure between zero and a maximum value. In order to analyze this phenomenon, first, we present the quasi-creep method, and then we validate this method using the finite element Abaqus Software based on the combined hardening model. Then we employ this method to evaluate the effect of internal pressure and thickness of the vessel on the amount of ratcheting strains in different cycles. In the end, the results of this research and the accuracy and speed of the quasi-creep method are stated.

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Chaaban, A., and M. Jutras. "Static Analysis of Buttress Threads Using the Finite Element Method." Journal of Pressure Vessel Technology 114, no. 2 (May 1, 1992): 209–12. http://dx.doi.org/10.1115/1.2929031.

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The finite element method has been used to investigate the stress field in threaded end closures of thick-walled high pressure vessels. A set of elastic analyses of vessels with 5, 8, 11, 15, 20 and 25 standard Buttress threads was used to propose a method for predicting the load distribution along the length of the thread. Root stress index factors in the region of the first three active threads are also included. The results of the present work contribute to the development of the new division of the ASME Pressure Vessel Code which is related to thick-walled high pressure vessels.

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Kobayashi, Satoshi, Mari Kawahara, and Shinji Ogihara. "408 Stress analysis of FW-CFRP thick-walled vessel." Proceedings of the Materials and processing conference 2007.15 (2007): 253–54. http://dx.doi.org/10.1299/jsmemp.2007.15.253.

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6

Ashworth, Vanessa E. T. M., and Gracielza Dos Santos. "Wood Anatomy of Four Californian Mistletoe Species (Phoradendron, Viscaceae)." IAWA Journal 18, no. 3 (1997): 229–45. http://dx.doi.org/10.1163/22941932-90001486.

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Secondary xylem characteristics were compared in four species of Phoradendron Nutt. (Viscaceae) native to California. All have extremely short, thick-walled vessel elements with simple perforation plates. They also share high vessel density, radial vessel arrangement, thick-walled fibres, and multiseriate, heterocellular rays. The fibres show considerable intrusive growth. Features of the vessel elements (i.e. vessel dimensions, arrangement, type of wall sculpturing) and calcium oxalate crystals in the ray parenchyma cells are useful diagnostic traits to separate species. Grooved vessel walls are shared by the morphologically similar P. villosum and P. macrophyllum. Differences between these two species may reflect contrasting drought response strategies pursued by respective hosts. Vulnerability and mesomorphy ratios of the wood of P. californicum are higher than those of P. pauciflorum and P. macrophyllum. Phoradendron pauciflorum has the most xeromorphic wood of the four species studied.

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7

Koh, S. K., and R. I. Stephens. "Fatigue Life Prediction of an Autofrettaged Thick-Walled Pressure Vessel With an External Groove." Journal of Pressure Vessel Technology 113, no. 3 (August 1, 1991): 368–74. http://dx.doi.org/10.1115/1.2928768.

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An autofrettaged thick-walled pressure vessel with an external groove subjected to a pulsating internal pressure can have fatigue failures at the external groove root due to the combination of tensile autofrettage residual stress, operating stress, and stress concentration. To predict the fatigue life of the autofrettaged thick-walled pressure vessel with an external groove, the local strain approach was applied. The residual stress distribution due to autofrettage and the operating stress distribution due to internal pressure were determined using finite element analysis which resulted in theoretical stress concentration factors. To account for the mean stress effects on the fatigue life prediction of the pressure vessel, low-cycle fatigue behavior with several strain ratios was obtained using smooth axial specimens taken from the ASTM A723 thick-walled steel pressure vessel. Fatigue life predictions were made by incorporating the local strains determined from the linear rule and Neuber’s rule and the Morrow and SWT mean stress parameters determined from low-cycle fatigue tests. The predicted fatigue lives were within factors of 2 to 4, compared to simulated experimental fatigue lives based upon fatigue cracks of 2.5 mm in length. These procedures appear to be realistic for evaluating fatigue lives for this complex pressure vessel.

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8

Kholdi, Mohsen, Abbas Loghman, Hossein Ashrafi, and Mohammad Arefi. "Analysis of thick-walled spherical shells subjected to external pressure: Elastoplastic and residual stress analysis." Proceedings of the Institution of Mechanical Engineers, Part L: Journal of Materials: Design and Applications 234, no. 1 (October 21, 2019): 186–97. http://dx.doi.org/10.1177/1464420719882958.

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When cylindrical and spherical vessels are subjected to the internal pressure, tensile tangential stresses are created throughout the thickness, the maximum of which are located at the inner surface of the vessels. To improve the performance of these vessels, autofrettage process has been devised to produce beneficial compressive residual stresses at the inner part of such vessels. The question arises whether the process such as autofrettage can be useful for vessels such as submarines or other thick walled tanks, which are used in deep sea waters and, therefore, subjected to high external hydrostatic pressure causing both radial and tangential stresses to be compressive across the thickness. On the other hand, is the residual stresses created by unloading from an external pressure beyond elastic limit beneficial and enhance their performances? In this study, elastoplastic and residual stresses in a thick-walled spherical vessel under external hydrostatic pressure has been investigated. The material behavior is considered to be elastic-perfectly plastic. Von Misses yield criterion is used to obtain initial yield point and for the ideal elastoplastic regime analytical relations are presented. It has been found that by applying external hydrostatic pressure yielding process will start from inside of the sphere. Finally after unloading, residual tensile stresses are created at the inner part of the vessel which is useful for the vessel. The residual stresses and the condition of reverse yielding is studied in this paper.

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9

Moini, Hossein, and Thomas P. Mitchell. "Stress analysis of a thick-walled pressure vessel nozzle junction." International Journal of Pressure Vessels and Piping 46, no. 1 (January 1991): 67–74. http://dx.doi.org/10.1016/0308-0161(91)90069-e.

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10

Maleki, M., G. H. Farrahi, B. Haghpanah Jahromi, and E. Hosseinian. "Residual stress analysis of autofrettaged thick-walled spherical pressure vessel." International Journal of Pressure Vessels and Piping 87, no. 7 (July 2010): 396–401. http://dx.doi.org/10.1016/j.ijpvp.2010.04.002.

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11

Krasiński, Maciej, Marek Stodulski, and Andrzej Trojnacki. "Stress Modification in Multi-Layer Walls of Expanded Pressure Vessels." Key Engineering Materials 542 (February 2013): 81–95. http://dx.doi.org/10.4028/www.scientific.net/kem.542.81.

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The paper deals with a stress modification in thick-walled multi-layer pressure vessels widely used in every field of high pressure technology. The stress modification is obtained by means of initial (residual) stresses which are introduced into the vessel structure during the manufacturing process. Certain technological parameters are determined. Their realization leads to the equivalent stresses being more uniformly distributed across the vessel wall under the operating pressure. As a consequence the load carrying capacity of the multi-layer vessel increases as compared with the solid wall without additional treatment. The analytical approach as well as the finite-element method are used to solve the problem. A special attention is focused on the unconventional original Polish technology in which the internal pressure is applied to form the thick multi-layer cylinder wall through subsequent expansion of thin layers. The advantages of the proposed method are illustrated by the numerical example of the expanded multi-layer high-pressure vessel with modified initial stress distribution.

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12

Eggert, R. J. "Design Variation Simulation of Thick-walled Cylinders." Journal of Mechanical Design 117, no. 2A (June 1, 1995): 221–28. http://dx.doi.org/10.1115/1.2826126.

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Thick-walled cylinders exposed to high, static internal pressures may experience both elastic and plastic deformation. Primary design considerations include loads, geometry and material properties. However, variations in geometry and material properties due to conventional manufacturing processes, and variations of internal pressure due to actual usage patterns, propagate through the system resulting in off-design stresses and strains which may cause failure. These variations can be evaluated using probabilistic methods which are discussed in this paper. Von Mises-distortion energy yield theory is presented to predict elastic, plastic and residual stresses in thick-walled cylinders. The design variation simulation method using Monte Carlo simulation and available statistical information is used to design a pressure vessel for servo-hydraulic experiments. The use of autofrettage to induce favorable compressive stresses at the inner bore, thereby improving the margin of safety and overall reliability, is also presented.

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13

Huang, Chi Chen, Hsin Yen Fan, Ching Hua Hung, Jung Chung Hung, and Chia Rung Lin. "Three Dimensional Finite Element Analysis on Neck-Spinning Process of Thick-Walled Tube at an Elevated Temperature." Advanced Materials Research 579 (October 2012): 269–77. http://dx.doi.org/10.4028/www.scientific.net/amr.579.269.

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Tube spinning is a metal forming process used to manufacture axisymmetric products. This study chose a seamless thick-walled steel tube to manufacture a high pressure vessel. Finite element analysis was successfully applied to the neck-spinning process of a thin-walled tube; however, previous research has not investigated the neck-spinning process of thick-walled tubes. Therefore, the aim of this research was to investigate numerically the neck-spinning process of thick-walled tubes at an elevated temperature. The commercial software Abaqus/Explicit was adopted in the simulation. This paper compares experimental and simulation results on thickness distribution and outer contour of the spun tube. During the final stage, the average deviations between the simulation and experiment were 6.74% in thickness and 4.97% in outer contour. The simulation results correspond with those derived in the experiment.

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14

Koh, Seung-Kee. "Residual stress analysis of an external grooved thick-walled pressure vessel." KSME Journal 7, no. 3 (September 1993): 194–202. http://dx.doi.org/10.1007/bf02970964.

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15

Li, Guiqin, Xuechao Deng, Haoju Song, and Baoqing Zhang. "Research on Autofrettage Mechanism in Ultra-High Pressure Thick-walled Vessel." Journal of Physics: Conference Series 1802, no. 2 (March 1, 2021): 022001. http://dx.doi.org/10.1088/1742-6596/1802/2/022001.

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16

Zhu, G., J. Jiang, Z. Wang, and D. G. Moffat. "Pressure Vessel Manufacture using the Chinese Ribbon Winding Technique." Proceedings of the Institution of Mechanical Engineers, Part E: Journal of Process Mechanical Engineering 203, no. 2 (August 1989): 85–91. http://dx.doi.org/10.1243/pime_proc_1989_203_194_02.

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During the past 20 years a technique has been developed in the People's Republic of China for manufacturing thick-walled pressure vessels using thin steel ribbons, helically wound under tension onto a thin inner steel core. The technique is described herein and the advantages claimed are outlined, together with brief descriptions of some related areas of development.

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17

Heklau, Heike, Peter Gasson, Fritz Schweingruber, and Pieter Baas. "Wood Anatomy of Chenopodiaceae (Amaranthaceae s.l.)." IAWA Journal 33, no. 2 (2012): 205–32. http://dx.doi.org/10.1163/22941932-90000090.

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The wood anatomy of the Chenopodiaceae is distinctive and fairly uniform. The secondary xylem is characterised by relatively narrow vessels (<100 μm) with mostly minute pits (<4 μm), and extremely narrow vessels (<10 μm intergrading with vascular tracheids in addition to “normal” vessels), short vessel elements (<270 μm), successive cambia, included phloem, thick-walled or very thick-walled fibres, which are short (<470 μm), and abundant calcium oxalate crystals. Rays are mainly observed in the tribes Atripliceae, Beteae, Camphorosmeae, Chenopodieae, Hablitzieae and Salsoleae, while many Chenopodiaceae are rayless. The Chenopodiaceae differ from the more tropical and subtropical Amaranthaceae s.str. especially in their shorter libriform fibres and narrower vessels. Contrary to the accepted view that the subfamily Polycnemoideae lacks anomalous thickening, we found irregular successive cambia and included phloem. They are limited to long-lived roots and stem borne roots of perennials (Nitrophila mohavensis) and to a hemicryptophyte (Polycnemum fontanesii). The Chenopodiaceae often grow in extreme habitats, and this is reflected by their wood anatomy. Among the annual species, halophytes have narrower vessels than xeric species of steppes and prairies, and than species of nitrophile ruderal sites.

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18

Kantor, B., A. Kundeleff, and A. Martynenko. "P042 Effects of initial stretches on blood flow in thick-walled vessel." Journal of Biomechanics 31 (July 1998): 76. http://dx.doi.org/10.1016/s0021-9290(98)80155-3.

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19

Koh, S. K., S. I. Lee, S. H. Chung, and K. Y. Lee. "Fatigue design of an autofrettaged thick-walled pressure vessel using CAE techniques." International Journal of Pressure Vessels and Piping 74, no. 1 (November 1997): 19–32. http://dx.doi.org/10.1016/s0308-0161(97)00066-5.

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20

Watashi, K., S. Kanazawa, H. Umeda, A. Koid, A. Imazu, and H. Yoshida. "Creep—fatigue test of a thick-walled vessel under thermal transient loadings." Nuclear Engineering and Design 116, no. 3 (September 1989): 423–41. http://dx.doi.org/10.1016/0029-5493(89)90101-5.

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21

Hu, Zhong. "Design of two-pass swage autofrettage processes of thick-walled cylinders by computer modeling." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 233, no. 4 (April 13, 2018): 1312–33. http://dx.doi.org/10.1177/0954406218770221.

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An ever-increasing industrial demand for pressurized thick-walled cylindrical components drives research and practice to increase their strength–weight ratio, extend their fatigue life, or to increase their pressure-carrying capacity. This can be achieved through an energy-efficient and safe two-pass swage autofrettage process by generating a favorable compressive residual hoop stress field in the inner layer of the cylinder prior to use. In this paper, a two-pass swage autofrettage process of a thick-walled cylinder was systematically investigated based on finite element analysis. A 105 mm cannon barrel made of high-pressure vessel steel ASTM A723-1130 was taken as a case study. An elastic nonlinear-hardening plastic material model with the Bauschinger effect was adopted. The mandrel’s axial pushing forces during swage autofrettage processes were analyzed. A 30–35% reduction in mandrel’s pushing forces has been achieved in the two-pass process. The residual stresses in swage autofrettaged thick-walled cylinders were predicted. The results of computer modeling were in agreement with neutron diffraction measurements. A maximum 18% reduction in von Mises stress in the swage autofrettaged thick-walled cylinders under an elastic-limit working pressure was identified. A maximum 31% increase in pressure-carrying capacity for the swage autofrettaged thick-walled cylinders was revealed. The optimum radial interference was proposed. Results from the two-pass process were compared with those from the single-pass process.

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22

卜, 宏利. "Software System of Ultrasonic Nondestructive Testing Technology for Thick-Walled Composite Pressure Vessel." Instrumentation and Equipments 07, no. 03 (2019): 193–201. http://dx.doi.org/10.12677/iae.2019.73026.

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OKUNO, Hiroto, Hideo KOEDA, Teruo TAKAHASHI, and Hirohumi TADA. "Optimization of autofrettage method for thick-walled pressure vessel by using FEM analysis." Proceedings of Conference of Hokkaido Branch 2002.42 (2002): 184–85. http://dx.doi.org/10.1299/jsmehokkaido.2002.42.184.

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24

Koh, S. K. "FATIGUE LIFE OF AN AUTOFRETTAGED THICK-WALLED PRESSURE VESSEL WITH AN EXTERNAL GROOVE." Fatigue & Fracture of Engineering Materials & Structures 19, no. 1 (April 2, 2007): 15–25. http://dx.doi.org/10.1111/j.1460-2695.1996.tb00928.x.

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Koh, S. K., and R. I. Stephens. "Stress analysis of an autofrettaged thick-walled pressure vessel containing an external groove." International Journal of Pressure Vessels and Piping 46, no. 1 (January 1991): 95–111. http://dx.doi.org/10.1016/0308-0161(91)90071-9.

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26

Kargarnovin, M. H., A. Rezai Zarei, and H. Darijani. "Wall thickness optimization of thick-walled spherical vessel using thermo-elasto-plastic concept." International Journal of Pressure Vessels and Piping 82, no. 5 (May 2005): 379–85. http://dx.doi.org/10.1016/j.ijpvp.2004.10.001.

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27

Li, Hong Jun, Xun Huang, Di Liu, and Qiang Ding. "Fatigue Evaluation of Autofrettaged Thick-Walled Cylinders with a Radial Cross-Bore." Advanced Materials Research 1025-1026 (September 2014): 104–11. http://dx.doi.org/10.4028/www.scientific.net/amr.1025-1026.104.

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The fatigue life of autofrettaged thick-walled cylinders with a radial cross-bore is investigated by applying inelastic finite element analysis with cyclic pressure loading. A non-linear kinematic hardening model considering bauschinger effect is used for determining cyclic plastic strain ranges in fatigue evaluations. A macro is written in ANSYS to calculate the equivalent alternating stress intensity, based on the ASME Boiler and Pressure Vessel Code. For a specific cyclic load level, a distinct optimum autofrettage pressure is identified by plotting autofrettage pressure against the equivalent alternating stress intensity and the number of cycles from design fatigue data. The optimum autofrettage pressure was found in the range of 80.5%-92.5% of limit pressure. The hydrotest had little influence on the fatigue life when the thick-walled cylinder was autofrettaged with an optimum autofrettage pressure.

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Desjardins, J. L., D. J. Burns, and J. C. Thompson. "A Weight Function Technique for Estimating Stress Intensity Factors for Cracks in High Pressure Vessels." Journal of Pressure Vessel Technology 113, no. 1 (February 1, 1991): 10–21. http://dx.doi.org/10.1115/1.2928720.

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This paper describes a computationally efficient weight function technique which can be used to estimate the opening-mode stress intensity factor around the perimeter of planar surface or embedded cracks. The accuracy of the weight function itself and of the numerical quadrature schemes adopted are verified for elliptical cracks with a wide range of aspect ratios. The technique is then applied to longitudinal-radial cracks at the inner surface, including crossbores, of thick-walled pressure vessels. The results obtained for a wide range of crack depths, aspect ratios and vessel diameter ratios agree well with the predictions obtained by others using finite element, boundary element and modified mapping collocation methods, as well as with previously unpublished experimental data. The paper also considers the applicability of the ASME Boiler and Pressure Vessel Code procedures for estimating K1 for these defects.

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Faury, Gilles, Gail M. Maher, Dean Y. Li, Mark T. Keating, Robert P. Mecham, and Walter A. Boyle. "Relation between outer and luminal diameter in cannulated arteries." American Journal of Physiology-Heart and Circulatory Physiology 277, no. 5 (November 1, 1999): H1745—H1753. http://dx.doi.org/10.1152/ajpheart.1999.277.5.h1745.

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Resistance in blood vessels is directly related to the inner (luminal) diameter (ID). However, ID can be difficult to measure during physiological experiments because of poor transillumination of thick-walled or tightly constricted vessels. We investigated whether the wall cross-sectional area (WCSA) in cannulated arteries is nearly constant, allowing IDs to be calculated from outer diameters (OD) using a single determination of WCSA. With the use of image analysis, OD and ID were directly measured using either transillumination or a fluorescent marker in the lumen. IDs from a variety of vessel types were calculated from WCSA at several reference pressures. Calculated IDs at all of the reference WCSA were within 5% (mean <1%) of the corresponding measured IDs in all vessel types studied, including vessels from heterozygote elastin knockout animals. This was true over a wide range of transmural pressures, during treatment with agonists, and before and after treatment with KCN. In conclusion, WCSA remains virtually constant in cannulated vessels, allowing accurate determination of ID from OD measurement under a variety of experimental conditions.

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Koh, S. K., and R. I. Stephens. "Improved fatigue life of an autofrettaged thick-walled pressure vessel with an external groove." International Journal of Pressure Vessels and Piping 58, no. 2 (January 1994): 131–45. http://dx.doi.org/10.1016/0308-0161(94)90076-0.

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Lei, Xiaowei, Jing Niu, Jianxun Zhang, Anqing Fu, and Yaorong Feng. "Failure Analysis of Weld Cracking in a Thick-Walled 2.25Cr-1Mo Steel Pressure Vessel." Journal of Materials Engineering and Performance 23, no. 4 (February 8, 2014): 1231–39. http://dx.doi.org/10.1007/s11665-014-0893-z.

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Ryu, Woo Seog, Sung Ho Kim, and Dae Whan Kim. "Welding Soundness of a Thick-Walled 9Cr-1Mo Steel." Materials Science Forum 654-656 (June 2010): 408–11. http://dx.doi.org/10.4028/www.scientific.net/msf.654-656.408.

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High Cr ferritic/martensitic steels are demanded to join using favorable welding processes with economical and metallurgical advantages in order to apply to the thick-walled reactor pressure vessel of a very high temperature gas cooled reactor. Narrow gap welding technology was adopted to weld a thick-walled 9Cr-1Mo-1W steel with thickness of 110mm. The welding integrity was checked by non-destructive examination, optical microscopy and hardness test, and the homogeneity through welding depth was checked by absorbed impact energy and tensile strength. The optimizing welding conditions resulted that a narrow U-grooved gap with almost parallel edges was sound in actual practice, and the coarse grain zone was minimized in the heat affected zone. The absorbed energy of 75±25 J through welding depth was acceptable in scatter band to check the uniformity through the welding depth. The ultimate tensile stress and yield stress were about the same through welding depth at 650±10 MPa and 500±10 MPa, indicating no difference through welding depth. Elongation was also almost same through depth, and the fracture surface was appeared as a normal. The weld metal had similar mechanical properties to base metal. The upper self energy of weld metal was 194J, and the ductile-brittle transition temperature was 30°C. The tensile behavior was the typical trend with temperature, and YS and UTS of weldment were slightly higher than base metal by nearly below 10%. Thus, it concluded that the soundness of the narrow gap welding of a thick-walled 9Cr-1Mo-1W steel was confirmed in terms of the welding uniformity through the depth and mechanical properties.

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Graham, Gwenda J., Eiichi Tanaka, Alec M. De Grand, Rita G. Laurence, Kozo Hoshino, Roger J. Hajjar, John V. Frangioni, and Robert Flaumenhaft. "Real-Time Imaging of Platelet-Rich Thrombi in Thick-Walled Blood Vessels Using Near-Infrared Fluorescence Light." Blood 108, no. 11 (November 16, 2006): 383. http://dx.doi.org/10.1182/blood.v108.11.383.383.

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Abstract Direct visualization of thrombus formation in real-time is limited by the fact that the vasculature is a closed system. Imaging of thrombi within arterioles and venules of small animals has been accomplished using fluorescent dyes that emit light in the visible spectrum. However, these agents are not able to penetrate large, thick-walled blood vessels and are therefore unable to detect thrombi in clinically important sites such as coronary, carotid, and femoral vessels. Near infrared light (NIR, 700–900 nm) demonstrates enhanced tissue penetration and less light scatter than visible light. By labeling platelets with IR-786, a heptamethine indocyanine-type fluorophore that emits NIR light, we have developed a reagent capable of detecting thrombi within thick-walled vessels of large animals. Optimal platelet loading occurred at 2 μM IR-786, resulting in an accumulation of 3 ×106 molecules/platelet. Normal platelet function was demonstrated by platelet aggregation and P-selectin surface expression studies. Clearance studies in 35 Kg Yorkshire pigs showed that IR-786-labeled platelets circulated for >2.5 h following infusion. IR-786-labeled platelets were next used in conjunction with an integrated NIR fluorescence video imaging system to digitally record thrombus formation in large vessels of pigs in real-time. Initially FeCl3 (oxidant injury) was utilized to induce clot formation in surgically exposed femoral arteries and IR-786-labeled platelets were shown to accumulate at the injury site with a signal to background ratio of 4.4±1.7. Thrombus growth was similarly detected and quantitated in coronary, carotid, and iliac arteries and veins. To assess potential applications of IR-786-labeled platelets for thrombus detection, thrombi were monitored in real-time, and quantified with respect to size and kinetics after electrocautery-induced injury to vessels, cutaneous incisions, intravascular stent insertion and introduction of embolic coils. Thrombolysis of formed IR-786-platelet-rich clots was also evaluated by the infusion of streptokinase and heparin, demonstrating dissolution of thrombi. Two color studies using IR-786-labeled platelets in conjunction with methylene blue, a near-infrared fluorescent blood pool agent used to assess vessel patency, showed that whilst the blood pool agent was more effective for assessing vessel patency, IR-786-labeled platelets were more sensitive for detecting and localizing thrombi within vessels. In addition, IR-786-labeled platelets were able to distinguish between actively growing and stabilized thrombi. IR-786-labeled platelets not only provide a useful tool to study mechanisms of thrombus formation but also afford a means of testing new anti-thrombotics and intravascular devices in vessels approximating the size of those in which clinically relevant thrombosis occurs. In addition, these pre-clinical studies indicate the utility of IR-786-labeled platelets as a contrast agent to detect intraoperative thrombosis, a complication of approximately 1–5% of vascular surgeries.

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Maarefdoust, Mahdi, and Pooria Akbarzade. "Limit Load Finite Element Analysis of Thick-Walled Cylinders with Surface Cracks under Combined Internal Pressure and Axial Tension." Advanced Materials Research 341-342 (September 2011): 416–20. http://dx.doi.org/10.4028/www.scientific.net/amr.341-342.416.

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Limit load analysis of defect free thick walled pipes and cylinders subjected to internal pressure and combined internal pressure and axial loading is commonly performed as part of integrity assessment procedures for transmission pipelines and pressure vessels across the industry. Moreover the potential impact of environmental assisted or accidental damage that result in creation of surface defects and consequently affects the ability of vessel to withstand the applied loading conditions. This paper attempts to demonstrate the effect of surface defects on the limit load of cylinders by use of finite element method. ABAQUS software has been used for FE analysis and modeling. Approximate analytical solutions for benchmark model have been used for validation/verification of numerical results.

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Lagerev, A. V. "Probability assessment of tightness loss pressure vessels during risk analysis technical devices for hazardous production facilities." Nauchno-tekhnicheskiy vestnik Bryanskogo gosudarstvennogo universiteta 7, no. 3 (September 25, 2021): 227–35. http://dx.doi.org/10.22281/2413-9920-2021-07-03-227-235.

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Thick-walled high-pressure vessels are a fairly common type of technical device as part of technological equipment operated at various hazardous production facilities. Reliability indicators of pressure vessels and their change during operation largely determine the indicators of failure-free operation of technological equipment as a whole, and potential failures of pressure vessels are subject to consideration when conducting a risk analysis of the operating equipment. The article discusses probabilistic and statistical approaches to solving the problem of predicting the resource of pressure vessels with fatigue failure of the neck at the design and operation stages. For the design stage, a technique is presented for modeling the processes of nucleation and development of a high-cycle fatigue crack, as well as a technique for determining the type of law and quantitative indicators of the distribution of the resource of a pressure vessel by the condition of loss tightness. For the operation stage, a method is presented for predicting the further growth of a diagnosed fatigue crack, as well as a method for determining the type of law and quantitative indicators of the distribution of the residual life of a pressure vessel by the condition of loss tightness.

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Levy, C., M. Perl, and Q. Ma. "Erosions and Their Effect on the Fatigue Life of Thick Walled, Autofrettaged, Pressurized Vessels." Journal of Pressure Vessel Technology 125, no. 3 (August 1, 2003): 242–47. http://dx.doi.org/10.1115/1.1593698.

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This paper summarizes the results that have been found in evaluating the effect of erosions on thick walled, autofrettaged, pressurized, cracked vessels. The problem is solved numerically via the FEM method. Autofrettage, based on von Mises yield criterion, is simulated by thermal loading and stress intensity factors (SIF’s) are determined by the nodal displacement method. SIF’s were evaluated for a variety of relative crack depths a/t and crack ellipticities a/c emanating from the tip of the erosion of various geometries, namely, (a) semi-circular erosions of small relative depths of the cylinder’s wall thickness t; (b) arc erosions for several dimensionless radii of curvature r′/t; and (c) semi-elliptical erosions with ellipticities of d/h. Other parameters evaluated were, in the cases of finite erosions, the semi-erosion length to the semicrack length Le/c, the erosion angular spacing α, and the autofrettage level. First, we summarize the differences found between a vessel with one erosion and one with multiple erosions. We show that for full cylinder length erosions, the erosions tend to make smaller cracks more dangerous than larger cracks in fully autofrettaged vessels and that as the crack grows the stress intensity factor initially decreases. We then show that as the crack grows further, the effect is to increase the effective stress intensity factor (SIF) but also to practically void the existence of the erosion. We show further that lower levels of autofrettage will lead to higher effective SIF’s but that partially eroded cylinders (cylinders where erosions are a fraction of the cylinder length) lead to lower SIF’s. Affecting these values in all cases, of course, are the erosion geometry and depth as well as the crack geometry and depth.

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Hunter, Kendall S., Joseph A. Albietz, Po-Feng Lee, Craig J. Lanning, Steven R. Lammers, Stephen H. Hofmeister, Philip H. Kao, H. Jerry Qi, Kurt R. Stenmark, and Robin Shandas. "In vivo measurement of proximal pulmonary artery elastic modulus in the neonatal calf model of pulmonary hypertension: development and ex vivo validation." Journal of Applied Physiology 108, no. 4 (April 2010): 968–75. http://dx.doi.org/10.1152/japplphysiol.01173.2009.

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Developing clinical work suggests that vascular stiffening plays a role in the progression of pulmonary hypertension (PH), while recent studies in animal models of hypoxic PH have found significant proximal vascular stiffening in the diseased population. Here, we develop and validate a minimally invasive, clinically realizable method to estimate the local elastic modulus of the proximal pulmonary arteries from pressure-diameter (PD) data. PD measurements were made in the main pulmonary arteries of 16 calves; lumen diameter was assessed using color M-mode tissue Doppler imaging ultrasound, while pressure was measured via catheter. Two methods corresponding to thin-walled pressure vessel theory (“thin”) and Lame's equation for a thick-walled cylinder (“thick”) were used to approximate the artery elastic modulus from PD measurements. The harvested arteries were tested independently to determine their “true” ex vivo elastic modulus and stiffness. Both approximations displayed excellent correlation with ex vivo elastic modulus of the calf main pulmonary artery (thin r2 = 0.811; thick r2 = 0.844; both P < 0.01). Bland-Altman analysis indicated that the thick-walled approximation has better overall agreement with ex vivo modulus. The approximations displayed quantitatively distinct regression slopes that were statistically different ( P = 0.02). The elastic modulus of the main pulmonary artery can be reasonably estimated from combined color M-mode tissue Doppler imaging ultrasound and catheter pressure measurements in calves. Such measurements may be a valuable tool in the diagnosis and treatment of human PH.

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Lee, Song-In, and Seung-Kee Koh. "Residual stress effects on the fatigue life of an externally grooved thick-walled pressure vessel." International Journal of Pressure Vessels and Piping 79, no. 2 (February 2002): 119–26. http://dx.doi.org/10.1016/s0308-0161(01)00132-6.

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Hasheminejad, Seyyed M., Vahid Rabbani, and Mahdi Alaei-Varnosfaderani. "Active transient elasto-acoustic response damping of a thick-walled liquid-coupled piezolaminated cylindrical vessel." Mechanics Based Design of Structures and Machines 44, no. 3 (June 14, 2015): 189–211. http://dx.doi.org/10.1080/15397734.2015.1048461.

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40

Levy, C., M. Perl, and N. Kokkavessis. "Three-Dimensional Interaction Effects in an Internally Multicracked Pressurized Thick-Walled Cylinder—Part II: Longitudinal Coplanar Crack Arrays." Journal of Pressure Vessel Technology 118, no. 3 (August 1, 1996): 364–68. http://dx.doi.org/10.1115/1.2842201.

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In the first part of this paper, the interaction effects among many radial, internal, semi-circular, and semi-elliptical cracks in a pressurized, thick-walled vessel were quantified. In the present paper, the mode I stress intensity factor (SIF) distribution for numerous longitudinal coplanar, internal, semi-circular, and semi-elliptical arrays of surface cracks in an infinite, pressurized, thick-walled cylinder are evaluated. The 3-D analysis is performed by the finite element (FE) method and the submodeling technique, employing singular elements along the crack front. The effects of dense and sparse interacting longitudinal coplanar crack arrays on the SIFs are studied for a wide range of crack depth to wall thickness ratios, a/t, from 0.05 to 0.6; and, for various ellipticities of the crack, i.e., the ratio of the crack depth to semi-crack length, a/c, from 0.2 to 2.0. An analysis is performed to determine the influence of the three major parameters—crack density, crack ellipticity, and crack depth—on the interaction effects between adjacent cracks. The results clearly indicate that crack density, and, in some cases, ellipticity have opposing effects on the SIF of longitudinal crack arrays as compared to radial crack arrays. As a result of these contrasting behaviors, thick-walled cylinders having combined longitudinal and radial crack arrays would need further study.

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Pandey, Krishna Murari, Abhijit Dey, and P. L. Choudhury. "Buckling Behaviour of Circular Ring Stiffened Filament Wound Composite Pressure Hull through Finite Element Analysis." Applied Mechanics and Materials 656 (October 2014): 288–97. http://dx.doi.org/10.4028/www.scientific.net/amm.656.288.

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The aim of present study was investigate the buckling pressure of moderately thick-walled filament-wound carbon–epoxy stiffened composite pressure vessel subjected to external hydrostatic pressure through finite element analysis and compare the result with un-stiffened filament wound carbon/epoxy composite pressure vessel used in under water vehicle applications. The winding angles were [±30/90] FW, [±45/90] FW and [±60/90] FW. ANSYS 14.0 APDL, a commercial finite element software package successfully predicted the buckling pressure of filament-wound composite pressure vessel with a deviation much higher than the results of un-stiffened filament wound composite cylinder .All the finite element analysis shows that the composite pressure vessel with winding pattern [±60/90] FW has the higher value of critical buckling pressure. Major failure modes in both the analysis were dominated by the helical winding angles.

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Roach, D. P., and T. G. Priddy. "Effect of Material Properties on the Strain to Failure of Thick-Walled Cylinders Subjected to Internal Pressure." Journal of Pressure Vessel Technology 116, no. 2 (May 1, 1994): 96–104. http://dx.doi.org/10.1115/1.2929582.

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The determination of the fully plastic response and pressure limit of a pressure vessel is of considerable importance in design, especially in autofrettage considerations. This paper presents the results of an experimental study which measured the maximum internal pressure which can be applied to thick-walled cylindrical vessels. Both aluminum and steel, with material properties ranging from ductile to brittle, were tested at stress levels through plastic and strain hardening ranges to fracture. From these tests, the pressure-expansion and through-thickness yielding characteristics were determined for these specimens. It is shown that a strain-to-failure criterion, based on the triaxiality of stress in the critical region, can be used to predict the complete pressure versus strain relations and maximum pressure for these cylinders. A simple tension-true stress-strain relation of the material is employed to analytically predict the response of the cylinder into the plastic regime. Finally, simplified theoretical and empirical formulas for bursting pressures are checked against the experimental results.

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Jahanian, S. "Thermoelastoplastic Stress Analysis of a Thick-Walled Tube of Nonlinear Strain Hardening." Journal of Mechanical Design 118, no. 3 (September 1, 1996): 340–46. http://dx.doi.org/10.1115/1.2826890.

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In pressure vessel technology or nuclear power plants, some of the mechanical components are often subjected to rapid heating. If the temperature gradient during such process is high enough, thermoelastoplastic stresses may be developed in the components. These plastic deformations are permanent and may result in the incremental deformation of the structure in the long term. Accordingly, determination of thermoelastoplastic stresses during this process is an important factor in design. In this paper, a thick-walled cylinder of nonlinear strain hardening is considered for the thermoelastoplastic analysis. The properties of the material are assumed to be temperature dependent. The cylinder is subject to rapid heating of the inside surface while the outside surface is kept at the room temperature. A quasi-static and uncoupled thermoelastoplastic analysis based on incremental theory of plasticity is developed and a numerical procedure for successive elastic approximation is presented. The thermoelastoplastic stresses developed during this process are also presented. The effect of strain hardening and temperature dependency of material on the results are investigated.

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44

Xinying, Zhang, Pieter Baas, and Alberta M. W. Mennega. "Wood Anatomy of Bhesa Sinica (Celastraceae)." IAWA Journal 11, no. 1 (1990): 57–60. http://dx.doi.org/10.1163/22941932-90001144.

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The wood anatomy of Bhesa sinica (Chang ' Liang) Chang ' Liang, the only species of the genus occurring in China, is described in detail and compared with other Celastraceae. Bhesa sinica closely resembles other species of the genus, in e. g. vessels mainly in radial multiples, exclusively scalariform perforations, large and (almost) simple vessel-ray pits; parenchyma in fine irregular bands, in long (over 8-celled) strands; thick-walled, non septate libriform fibres; 1-5-seriate heterocellular rays, and prismatic crystals in chambered axial and ray parenchyma cells. This combination of characters is not known to occur in any of the other genera of the Celastraceae, and most individual wood anatomical character states of Bhesa are also unusual within the family. The isolated position of the genus in the Celastraceae is discussed.

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Ishiguri, F., M. Takeuchi, K. Makino, I. Wahyudi, Y. Takashima, K. Iizuka, S. Yokota, and N. Yoshizawa. "Cell Morphology and wood properties of Shorea Acuminatissima Planted in Indonesia." IAWA Journal 33, no. 1 (2012): 25–38. http://dx.doi.org/10.1163/22941932-90000077.

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In view of the importance of long-rotation plantation forestry in SE Asia to limit soil erosion, the cell morphology and wood properties of 35-yearold plantation trees of yellow meranti, Shorea acuminatissima Sym. were studied. To understand the effects of growth rate on cell morphology and wood properties, 131 trees in a stand were classified according to their stem diameter as fast-, medium-, and slow-growing. Five trees in each category were selected for determining the cell morphology and wood properties. There were significant differences in vessel diameter, vessel frequency, and cell wall thickness of wood fibers in the three categories. The fast-growing trees had a relatively low frequency of wide vessels and thick-walled wood fibers. However, no significant differences in basic density or compressive strength parallel to grain were identified in the three categories. The radial variation in the cell morphology and wood properties showed an almost identical pattern in the three categories, suggesting that xylem maturation depends on the cambial age rather than growth rate.

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Griffiths, Roger R. "Investigation into a major crack that occurred during fabrication of a thick walled alloy pressure vessel." International Journal of Pressure Vessels and Piping 79, no. 8-10 (August 2002): 591–95. http://dx.doi.org/10.1016/s0308-0161(02)00086-8.

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Grytsan, Andrii, Thomas Eriksson, Paul Watton, and T. Gasser. "Growth Description for Vessel Wall Adaptation: A Thick-Walled Mixture Model of Abdominal Aortic Aneurysm Evolution." Materials 10, no. 9 (August 25, 2017): 994. http://dx.doi.org/10.3390/ma10090994.

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Kirichok, V. V., and V. M. Torop. "Modeling A Circumferential Crack In Pipe Area Of A Flat Bottom Of Thick-walled Pressure Vessel." Tehničeskaâ diagnostika i nerazrušaûŝij kontrolʹ 2019, no. 3 (September 28, 2019): 8–12. http://dx.doi.org/10.15407/tdnk2019.03.01.

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49

Koh, S. "Fatigue life simulation and estimation of an autofrettaged thick-walled pressure vessel with an external groove." International Journal of Fatigue 18, no. 1 (January 1996): 49–56. http://dx.doi.org/10.1016/0142-1123(96)82762-9.

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Jois, Kumar C., Marcus Welsh, Thomas Gries, and Johannes Sackmann. "Numerical Analysis of Filament Wound Cylindrical Composite Pressure Vessels Accounting for Variable Dome Contour." Journal of Composites Science 5, no. 2 (February 11, 2021): 56. http://dx.doi.org/10.3390/jcs5020056.

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In this work, the stress distribution along cylindrical composite pressure vessels with different dome geometries is investigated. The dome contours are generated through an integral method based on shell stresses. Here, the influence of each dome contour on the stress distribution at the interface of the dome-cylinder is evaluated. At first, the integral formulation for dome curve generation is presented and solved for the different dome contours. An analytical approach for the calculation of the secondary stresses in a cylindrical pressure vessel is introduced. For the analysis, three different cases were investigated: (i) a polymer liner; (ii) a single layer of carbon-epoxy composite wrapped on a polymer liner; and (iii) multilayer carbon-epoxy pressure vessel. Accounting for nonlinear geometry is seen to have an effect on the stress distribution on the pressure vessel, also on the isotropic liner. Significant secondary stresses were observed at the dome-cylinder interface and they reach a maximum at a specific distance from the interface. A discussion on the trend in these stresses is presented. The numerical results are compared with the experimental results of the multilayer pressure vessel. It is observed that the secondary stresses present in the vicinity of the dome-cylinder interface has a significant effect on the failure mechanism, especially for thick walled cylindrical composite pressure vessel. It is critical that these secondary stresses are directly accounted for in the initial design phase.

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Journal articles on the topic 'Thick-walled vessel'

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