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Journal articles on the topic 'Pressure vessels'
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1
Cui, Yi Hu, Jun Cheng Jiang, Yuan Yu, and Qing Wu Zhang. "Initial Pressure Influence on Explosion Pressures of Methane-Air Deflagrations in Linked Vessels." Advanced Materials Research 936 (June 2014): 2130–34. http://dx.doi.org/10.4028/www.scientific.net/amr.936.2130.
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An experimental study on pressure evolution during closed explosion and venting progress of methane–air mixtures ([CH4=10%]) in linked vessels was performed, for systems at various initial pressures (P0=0-0.08MPa). The effects of initial pressure on regularity of pressure variation in vessels were discussed. For the closed explosion in isolated vessel, the higher level of the initial pressure in isolated big vessel is, the larger the peak pressure and rate of pressure rise is, and the peak pressure increases nonlinearly with initial pressure; For closed explosion in linked vessels, the higher initial pressure within the linked vessels system leads to the higher peak pressures in two vessels and there is an approximate linear relationship between them, which is similar to explosion in isolated vessel. For vented explosion in linked vessels at higher initial pressure, venting has poorer effect on protection of the linked vessels.
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Guan, Gong Shun, Bao Jun Pang, and Yue Ha. "Investigation into Damage of Aluminum Gas-Filled Pressure Vessels under Hypervelocity Impact." Key Engineering Materials 348-349 (September 2007): 785–88. http://dx.doi.org/10.4028/www.scientific.net/kem.348-349.785.
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Impacts of meteoroids and space debris on pressure vessels can have detrimental consequences for any mission. Depending on the parameters of the impacting particle and the characteristic of the vessel, the damages can range from relatively uncritical craters in the vessel’s surface to the catastrophic bursting of vessels, which besides the loss of vessel may result in severe secondary damages to surrounding components. In order to investigate failure mechanisms of thin-walled aluminum pressure vessels under hypervelocity impact of space debris, a non-powder two-stage light gas gun was used to launch Al-sphere projectiles impacting on unshielded and shielded vessels. Damage patterns and mechanisms leading to catastrophic rupture are discussed. Experimental results indicate that the impact kinetic energy of the projectile and the gas pressure in the vessel have an important effect on the damage modes of the vessel. On the one hand, high pressure gas can lead to a vessel blast. On the other hand, high pressure gas can mitigate the impact of the debris cloud on the rear wall of the vessel. Catastrophic rupture of unshielded gas-filled vessels can be avoided when the impact energy is less than a certain limit value. When the bumper is perforated, damage of shielded pressure vessel might be fatal for vessels with high gas pressure.
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Kapali, A., H. P. Neopane, S. Chitrakar, K. P. Shrestha, and P. Sapkota. "Pressure fluctuation measurement in pressure vessels." IOP Conference Series: Earth and Environmental Science 1037, no. 1 (June 1, 2022): 012052. http://dx.doi.org/10.1088/1755-1315/1037/1/012052.
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Abstract Pressure vessels are mechanical devices that act as a reservoir of fluids at pressure more or less than atmospheric pressure. This research focuses on the application of the pressure vessel for hydraulic testing of hydro turbines to maintain uniform velocity profile and to suppress the pressure surge in the pipeline. An initial assumption for the design of a thin-walled horizontal type pressure vessel with the ellipsoidal type of head is based on the mathematical relations as per ASME code, Section VIII, Division I, for an operating pressure of 0.3 MPa and design pressure of 0.6 MPa. The pressure vessel has been placed, close to outlet of the main pump to prevent the water hammering in the pipeline. The measurement of the pressure fluctuations at the inlet, outlet, and inside of the vessel, due to the dynamic action of fluid forced by the pump are recorded. The study attempts to relate the use of pressure vessels to generate stable flow and pressure at the outlet for hydraulic testing of turbines.
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Earley, Scott, and Benjimen R. Walker. "Endothelium-dependent blunting of myogenic responsiveness after chronic hypoxia." American Journal of Physiology-Heart and Circulatory Physiology 283, no. 6 (December 1, 2002): H2202—H2209. http://dx.doi.org/10.1152/ajpheart.00125.2002.
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Blunted agonist-induced vasoconstriction after chronic hypoxia is associated with endothelium-dependent vascular smooth muscle (VSM) cell hyperpolarization and decreased vessel-wall Ca2+concentration ([Ca2+]). We hypothesized that myogenic vasoconstriction and pressure-induced Ca2+ influx would also be attenuated in vessels from chronically hypoxic (CH) rats. Mesenteric resistance arteries isolated from CH [barometric pressure (BP), 380 Torr for 48 h] or normoxic control (BP, 630 Torr) rats were cannulated and pressurized. VSM cell resting membrane potential was recorded at intraluminal pressures of 40–120 Torr under normoxic conditions. VSM cells in vessels from CH rats were hyperpolarized compared with control rats at all pressures. Inner diameter was maintained for vessels from control rats, whereas vessels from CH rats developed less tone as pressure was increased. Pressure-induced increases in vessel-wall [Ca2+] were also attenuated for arteries from CH rats. Endothelium removal restored myogenic constriction to vessels from CH rats and normalized VSM cell resting membrane potential and pressure-induced Ca2+ responses to control levels. Myogenic constriction and pressure-induced vessel-wall [Ca2+] increases remained blunted in the presence of nitric oxide (NO) synthase inhibition for arteries from CH rats. We conclude that blunted myogenic reactivity after chronic hypoxia results from a non-NO, endothelium-dependent VSM cell hyperpolarizing influence.
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Yan, C., ZR Wang, F. Jiao, and C. Ma. "Numerical simulation on structure effects for linked cylindrical and spherical vessels." SIMULATION 94, no. 9 (March 21, 2018): 849–58. http://dx.doi.org/10.1177/0037549718763081.
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This paper presents a simulation study on the methane–air mixture explosions through using the eddy-dissipation concept (EDC) model in FLUENT. The aims are to investigate the structure effects of methane–air mixture explosions in a spherical vessel, cylindrical vessel and different systems of cylindrical vessels connected with pipe. Meanwhile, in order to study the characteristics of methane-air mixture explosions in the linked vessels, changes of flame temperature and airflow velocity in the linked vessels are simulated and analyzed. The results suggest that the effect of structural changes of a single vessel on the gas explosion intensity is clear, and the explosion intensity of a spherical vessel is greater than that of a cylindrical vessel. The simulation results of different structural forms of a cylindrical vessel connected with pipelines show that the time to reach the peak value of explosion pressure is the shortest in the linked vessels, and the explosion pressure rising rate is highest at the vessel’s center. For the linked vessels, after ignition, the airflow ahead of the flame propagates to the secondary vessel, and the maximum airflow velocity of every monitoring point in the linked vessels increases. The detonation occurs when the flame propagates to the secondary vessel, which leads to a severe secondary explosion in the secondary vessel. The studies can provide an important reference for the safe design of industrial vessels.
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Walker, M., T. Reiss, and S. Adali. "Optimal Design of Laminated Cylindrical Pressure Vessels for Maximum External Pressure." Journal of Pressure Vessel Technology 119, no. 4 (November 1, 1997): 494–97. http://dx.doi.org/10.1115/1.2842335.
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Finite element solutions are presented for the optimal design of hemispherically and flat-capped symmetrically laminated pressure vessels subjected to external pressure. The effect of vessel length, radius, and wall thickness, as well as bending-twisting coupling and hybridization on the optimal ply angle and buckling pressure are numerically studied. Comparisons of the optimal fiber angles and maximum buckling pressures for various vessel geometries are made with those for a hybrid pressure vessel. The well-known golden section method is used to compute the optimum angle in each case.
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Blach, A. E., V. S. Hoa, C. K. Kwok, and A. K. W. Ahmed. "Rectangular Pressure Vessels of Finite Length." Journal of Pressure Vessel Technology 112, no. 1 (February 1, 1990): 50–56. http://dx.doi.org/10.1115/1.2928587.
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Design Rules in the ASME Code, Section VIII, Division 1, cover the design of unreinforced and reinforced rectangular pressure vessels. These rules are based on “infinitely long” vessels of non-circular cross section and stresses calculated are based on a linearized “small deflection” theory of plate bending. In actual practice, many pressure vessels can be found which are of finite length, often operating successfully under pressures two to three times as high as those permitted under the Code rules cited. This paper investigates the effects of finite length on the design formulae given by the ASME Code, and also a design method based on “large deflection” theory coefficients for short rectangular pressure vessels. Results based on analysis are compared with values obtained from finite element computations, and with experimental data from strain gage measurements on a test pressure vessel.
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Hoffman, J. I., and J. A. Spaan. "Pressure-flow relations in coronary circulation." Physiological Reviews 70, no. 2 (April 1, 1990): 331–90. http://dx.doi.org/10.1152/physrev.1990.70.2.331.
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The blood vessels that run on the surface of the heart and through its muscle are compliant tubes that can be affected by the pressures external to them in at least two ways. If the pressure outside these vessels is higher than the pressure at their downstream ends, the vessels may collapse and become Starling resistors or vascular waterfalls. If this happens, the flow through these vessels depends on their resistance and the pressure drop from their inflow to the pressure around them and is independent of the actual downstream pressure. In the first part of this review, the physics of collapsible tubes is described, and the possible occurrences of vascular waterfalls in the body is evaluated. There is good evidence that waterfall behavior is seen in collateral coronary arteries and in extramural coronary veins, but the evidence that intramural coronary vessels act like vascular waterfalls is inconclusive. There is no doubt that in systole there are high tissue pressures around the intramyocardial vessels, particularly in the subendocardial muscle of the left ventricle. The exact nature and values of the forces that act at the surface of the small intramural vessels, however, are still not known. We are not certain whether radial (compressive) or circumferential and longitudinal (tensile) stresses are the major causes of vascular compression; the role of collagen struts in modifying the reaction of vessel walls to external pressures is unknown but possibly important; direct examination of small subepicardial vessels has failed to show vascular collapse. One of the arguments in favor of intramyocardial vascular waterfalls has been that during a long diastole the flow in the left coronary artery decreases and reaches zero when coronary arterial pressure is still high: it can be as much as 50 mmHg in the autoregulating left coronary arterial bed and approximately 15-20 mmHg even when the vessels have been maximally dilated. These high zero flow pressures, especially during maximal vasodilatation, have been regarded as indicating a high back pressure to flow that is due to waterfall behavior of vessels that are exposed to tissue pressures.(ABSTRACT TRUNCATED AT 400 WORDS)
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Aceves, S. M., and G. D. Berry. "Thermodynamics of Insulated Pressure Vessels for Vehicular Hydrogen Storage." Journal of Energy Resources Technology 120, no. 2 (June 1, 1998): 137–42. http://dx.doi.org/10.1115/1.2795024.
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This paper studies the application of insulated pressure vessels for hydrogen-fueled light-duty vehicles. Insulated pressure vessels are cryogenic-capable pressure vessels that can be fueled with liquid hydrogen (LH2); low-temperature (46 K) compressed hydrogen (CH2); or ambient-temperature CH2. In this analysis, hydrogen temperatures, pressures, and venting losses are calculated for insulated pressure vessels fueled with LH2 or with low-temperature CH2, and the results are compared to those obtained in low-pressure LH2 tanks. Hydrogen losses are calculated as a function of daily driving distance during normal operation; as a function of time during long periods of vehicle inactivity; and as a function of initial vessel temperature during fueling. The results show that insulated pressure vessels have packaging characteristics comparable or better than those of conventional, low-pressure LH2 tanks, with greatly improved dormancy and much lower boil-off, and therefore appear to be a good alternative for vehicular hydrogen storage.
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Dongaonkar, R. M., T. L. Nguyen, C. M. Quick, J. Hardy, G. A. Laine, E. Wilson, and R. H. Stewart. "Adaptation of mesenteric lymphatic vessels to prolonged changes in transmural pressure." American Journal of Physiology-Heart and Circulatory Physiology 305, no. 2 (July 15, 2013): H203—H210. http://dx.doi.org/10.1152/ajpheart.00677.2012.
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In vitro studies have revealed that acute increases in transmural pressure increase lymphatic vessel contractile function. However, adaptive responses to prolonged changes in transmural pressure in vivo have not been reported. Therefore, we developed a novel bovine mesenteric lymphatic partial constriction model to test the hypothesis that lymphatic vessels exposed to higher transmural pressures adapt functionally to become stronger pumps than vessels exposed to lower transmural pressures. Postnodal mesenteric lymphatic vessels were partially constricted for 3 days. On postoperative day 3, constricted vessels were isolated, and divided into upstream (UP) and downstream (DN) segment groups, and instrumented in an isolated bath. Although there were no differences between the passive diameters of the two groups, both diastolic diameter and systolic diameter were significantly larger in the UP group than in the DN group. The pump index of the UP group was also higher than that in the DN group. In conclusion, this is the first work to report how lymphatic vessels adapt to prolonged changes in transmural pressure in vivo. Our results suggest that vessel segments upstream of the constriction adapt to become both better fluid conduits and lymphatic pumps than downstream segments.
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Shirwa, Feysal Mohamed. "Finite Element Analysis of Pressure Vessels Subjected to Uniform Internal Pressure Using Ansys Software." International Journal of Research and Innovation in Applied Science 07, no. 09 (2022): 20–26. http://dx.doi.org/10.51584/ijrias.2022.7902.
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This paper discusses the stresses developed in the pressure vessels having various thicknesses. Pressure vessels are intended to hold gases or liquids at a pressure substantially different from atmospheric pressure. Equations of static equilibrium along with free body diagrams will be used to determine the normal stress σ1 in the hoop direction and σ2 in the longitudinal direction also the von misses’ stresses. Also we will discuss the deformations and displacements to the pressure vessel using commercial finite element software called ANSYS for modelling and analyzing of the vessels. And the main results we found is that there is stress and deformation variation in the vessel according to thickness
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Reddy, Y. Srinivasa. "Fabrication and Experimental Investigation of Composite Pressure Vessel." International Journal for Research in Applied Science and Engineering Technology 11, no. 11 (November 30, 2023): 737–49. http://dx.doi.org/10.22214/ijraset.2023.56610.
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Abstract: Composite pressure vessels are an important type of high-pressure containers that are widely used in aerospace industries. The pressure vessels develop hoop stresses that are twice the longitudinal stresses. CFRP (Carbon Fiber Reinforced Polymer) composite materials with their higher specific strength and characteristics will result in reduction of weight of the structure when compared with isotropic materials like steel. The present work is aimed in understanding the behaviour of the Composite Pressure Vessel with variation of internal pressure. In this connection, a pressure vessel using CFRP (Carbon Fiber Reinforced Polymer) is fabricated which can hold liquids or gases under pressure and is tested at various pressures. The FEA tool ANSYS 14.5 is used to determine better fiber angle required for liquid storage, when the conventional low carbon steel cylinder is replaced with CFRP Pressure Vessel.
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Birk, A. M. "Thermal Protection of Pressure Vessels by Internal Wall Cooling During Pressure Relief." Journal of Pressure Vessel Technology 112, no. 4 (November 1, 1990): 427–31. http://dx.doi.org/10.1115/1.2929900.
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When pressure vessels are exposed to external fire impingement, high wall temperatures can result and these can lead to material degradation and the ultimate failure of the vessel. To protect against this possibility, vessels can be protected by means of pressure relief devices, external thermal barriers or external water spray cooling. This paper deals with a device that cools the walls of fire-impinged vessels carrying pressurized liquids by directing 2-phase fluid along the upper internal surface of the vessel when the vessel pressure relief valve is in action. The device consists of a concentric secondary internal shell that partitions the interior into a core region and an annulus. The bottom of the internal shell is open to allow communication between the two regions. When vapor is vented from the annulus, it results in significant fluid swelling in the annular space. This swelling results in large areas of the wall being wetted and cooled by liquid. Experimental results are presented for the case of a short electrically heated cylindrical vessel with and without the cooling device installed. From the limited tests conducted, it was shown that the device cools areas of the vessel wall that would normally have experienced high wall temperatures and possible material degradation.
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Liang, Jianguo, Lihua Liu, Zelin Qin, Xiaodong Zhao, Zhi Li, Uwayezu Emmanuel, and Jun Feng. "Experimental Study of Curing Temperature Effect on Mechanical Performance of Carbon Fiber Composites with Application to Filament Winding Pressure Vessel Design." Polymers 15, no. 4 (February 16, 2023): 982. http://dx.doi.org/10.3390/polym15040982.
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During the forming process of carbon fiber composite pressure vessels, the parameters of the curing and forming processes become one of the critical factors affecting the production cost and forming quality. The curing temperature of 4251 A4/B2 epoxy resin is measured in this research, and the effect of curing temperature on the mechanical properties of composite materials for winding is studied, which is finally verified in the test of pressure vessels. First, the actual curing temperature of the epoxy resin is tested and analyzed using differential scanning calorimetry (DSC). Second, under two different curing regimes, the tensile and flexural properties are tested by making pure epoxy resin matrix test pieces, Naval Ordnance Laboratory (NOL) rings, and carbon fiber composite unidirectional plates that affect the overall performance of composite pressure vessels. At the same time, the test results provide reliable process parameters for numerical simulation and manufacturing of pressure vessels. Finally, the filament-wound 35 MPa type III pressure vessel is cured and carried out using a hydraulic burst test. The results show the resin matrix has good fluidity and excellent interface bonding with carbon fiber when the curing temperature is 112 °C. Compared with the results in curing temperature of 100 °C, the tensile strength of the NOL ring reaches 2260.8 MPa, up by 22%. In the 90° direction, the tensile and flexural strengths of the unidirectional plates increase by 68.86% and 37.42%, respectively. In the 0° direction, the tensile and flexural strengths of the unidirectional plates increase by 5.82% and 1.16%, respectively. The pressure vessel bursting form is reasonable and meets the CGH2R standard. The bursting pressure of the vessel is up to 104.4 MPa, which verifies the rationality of the curing regime used in the curing process of the pressure vessel. Based on the results of this paper, the curing temperature affects the fluidity of the epoxy resin, which in turn affects the interfacial bonding properties of the composite, and the forming quality of the wound components and the pressure vessel, ultimately. When using 4251A4/B2 epoxy resin for wet winding pressure vessels, the choice of a 112 °C curing temperature will help improve the vessel’s overall performance. This work could provide reliable experience and insight into the curing process analysis of pressure vessel manufacturing.
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Rogers, T. K., A. G. Stewart, and A. H. Morice. "Effect of chronic hypoxia on rat pulmonary resistance vessels: vasodilatation by atrial natriuretic peptide." Clinical Science 83, no. 6 (December 1, 1992): 723–29. http://dx.doi.org/10.1042/cs0830723.
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1. We have investigated the vasoreactivity of isolated pulmonary resistance vessels of rats after acclimatization to chronic hypoxia in a normobaric, hypoxic chamber. Vasoconstriction, in response to KCl and prostaglandin F2α, and vasodilatation, in response to atrial natriuretic peptide, were studied isometrically in a small-vessel myograph. Resting tensions were set to simulate transmural pressures of 17.5 mmHg or 35 mmHg. 2. There were no significant differences between intergroup internal vessel diameters or maximal contractile responses to either agonist. Both control and chronically hypoxic vessels generated significantly greater active contractions at 35 mmHg than at 17.5 mmHg. There were significant positive correlations between vessel diameter and maximum contractility for both control and chronically hypoxic vessels, but when contraction was expressed as equivalent transmural pressure no correlation existed. 3. There was a significant increase in potency (as measured by the concentration necessary to produce 50% of the maximum response) of KCl in chronically hypoxic vessels compared with control vessels at 35 mmHg, but not at 17.5 mmHg. In contrast, the potency of prostaglandin F2α was significantly increased in chronically hypoxic vessels at 17.5 mmHg, but not at 35 mmHg. Thus the change in contractile responses of vessels from chronically hypoxic animals, in terms of maximal response and potency, is dependent on both resting pressure and agonist used. 4. After exposure to chronic hypoxia, atrial natriuretic peptide induced significantly greater maximal relaxation of pulmonary resistance vessels at both resting pressures, but its potency was unaffected.
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Zhen, Yaya, Zhirong Wang, Jinghong Wang, Cheng Wang, and Yangyang Cui. "Experimental and numerical study on connecting pipe and vessel size effects on methane–air explosions in interconnected vessels." Journal of Fire Sciences 36, no. 3 (February 26, 2018): 164–80. http://dx.doi.org/10.1177/0734904118760165.
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The size effects on a methane–air mixture explosion in the interconnected vessels were investigated in this article. The vessels were interconnected by pipes of various lengths or diameters. Varied pipe lengths were analyzed by experiment. The results indicate that the maximum explosion pressure and the maximum rate of pressure rise in the primary and secondary vessels increase with pipe length. To investigate the effects of pipe diameter and volume ratio on methane–air mixtures’ explosion in the interconnected vessels, a computational fluid dynamics model was implemented. The model was validated by comparison with experimental results. A fair agreement was observed between the simulation results and experimental data. The simulation results indicate that an increase in the pipe diameter will reduce the danger of explosion. The maximum explosion pressure in both vessels increases when the volume ratio increases. When the primary vessel is larger than the secondary vessel, the maximum rate of pressure rise in the primary vessel decreases with volume ratio. However, the maximum rate of pressure rise in the secondary vessel increases. The maximum rate of pressure rise changes inconspicuously while the secondary vessel is larger than the primary one. Hence, the cubic-root law is not applicable to an explosion in the interconnected vessels. These conclusions can support the safe design of chemical equipment.
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Liu, Dong Xia, Li Liang, and Xing Lei Bao. "Analysis of Optimal Autofrettage Pressure on CFRP Pressure Vessels Using ANSYS." Applied Mechanics and Materials 331 (July 2013): 184–88. http://dx.doi.org/10.4028/www.scientific.net/amm.331.184.
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For the pressure vessels made of high-strength Carbon Fiber Reinforced Plastics (CFRP) and Aluminum liner, the strength is provided by the CFRP, but the liner leak is always the bottleneck of the vessels’ safety. The carrying capacity and anti-fatigue ability of CFRP pressure vessels is largely depend on the elastic deformation range. In this research the principle of autofrettage is analyzed, the mechanical character of a certain 2 liters pressure vessel is analyzed using finite element software ANSYS, and the optimal autofrettage pressure is calculated by optimization method. The results showed that the stresses of the liner under working pressure were decreasing while applying the autofrettage pressure. The liner would gain the best plastic level under the appropriate autofrettage pressure.
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Salins, Sampath Suranjan, Mahesh Mohan, and Clifton Stephen. "Finite Element Investigation on the Performance of Pressure Vessel Subjected to Structural Load." Annales de Chimie - Science des Matériaux 45, no. 3 (June 30, 2021): 201–5. http://dx.doi.org/10.18280/acsm.450302.
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Pressure vessels are highly used in industries and in commercial purposes such as filtration, boiling, softening and hot water storage tanks. Pressure vessels are subjected to thermal loads and structural loads such as internal and external pressures which leads to its deformation. Present work focusses on the modeling of the pressure vessel according to standard dimensions using CREO 6.0 and analyzing it for three different materials and different pressure values using finite element approach. The materials considered in this study for the fabrication of pressure vessel are carbon steel, stainless steel, and titanium alloy. The finite element analysis results have been presented in graphical form. Results indicated that, titanium alloy is able to withstand high stresses and exhibited high factor of safety of 4.10. And among the steels, stainless steel demonstrated low structural performance.
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., Rao Yarrapragada K. S. S. "COMPOSITE PRESSURE VESSELS." International Journal of Research in Engineering and Technology 01, no. 04 (April 25, 2012): 597–618. http://dx.doi.org/10.15623/ijret.2012.0104011.
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Kuzborska, Zyta. "INFLUENCE OF AGE AND GENDER ON THE STRENGTH OF BLOOD VESSELS." CBU International Conference Proceedings 4 (September 17, 2016): 719–26. http://dx.doi.org/10.12955/cbup.v4.839.
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This article examines the effects of cardiovascular diseases that alter the diameter, wall thickness, and length of blood vessels. Depending on form and size of the damage, blood flow velocity, blood pressure, and stresses are affected in areas of diseased blood vessels. Through stimulating the deviations in the geometric shape of a blood-vessel wall, local blood pressure and stresses can arise from flow variation of blood vessels. This rise affects the blood-vessel wall and causes critical stresses likely to produce fissures in the blood vessels. It was found, that blood vessel pathology could cause blood flow velocity to increase up to 2.2 times and local blood pressure up to 3.4 times, and that human aging may have a significant influence on blood-vessel strength.
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Xi, Ping Yuan, and Fu Zhou Zhao. "Intelligent Design Research of Pressure Vessel." Advanced Materials Research 321 (August 2011): 204–7. http://dx.doi.org/10.4028/www.scientific.net/amr.321.204.
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Pressure vessel is not only the equipment used in the process industrial production, but also a more vulnerable to accidents special equipment. Under normal circumstances, in addition to bear the majority of media pressure, pressure vessels usually accompanied by the joint role of the high temperature, high pressure or media corrosion. Therefore, the design on the pressure vessels in anomaly conditions and the dynamic response not only helps to the research and development of warning surveillance and prevention technology about pressure vessels in anomaly conditions, but also contribute to the correct evaluation of the feasibility and reliability.So the simulated annealing algorithm based on penalty strategy is adopted to solver the optimization model of pressure vessels.
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De Queiroz Feitosa, Rômulo, and Aêda Monaliza Cunha de Sousa. "SAFETY INSPECTION OF PRESSURE VESSELS AT AN ENGINE GRINDER IN AGRESTINA-PE." Journal of Interdisciplinary Debates 4, no. 01 (March 31, 2023): 22–46. http://dx.doi.org/10.51249/jid.v4i01.1252.
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Pressure vessels are critical components in internal combustion engines as they withstand high pressures of oil, air, steam or other fluids. Failure of a pressure vessel can result in loss of containment, personal injury, equipment damage and, in severe cases, even explosions. Therefore, it is crucial to carry out periodic and rigorous inspections of these vessels in an engine overhaul to ensure their integrity and safety. This article discusses the steps of inspection in pressure vessels in an engine grinding plant, including inspection of pressure vessels containing argon gas stored to perform aluminum welding, as well as verification of design specifications, external visual evaluation, dimensional verification, ray inspection, visual inspection on compressors, which is important to extend its useful life and prevent accidents, inspection is performed according to specific standards and codes, such as ASME and API, and can be performed by internal or external inspectors, depending on the complexity of the equipment
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Sutton, Don W., and Geert W. Schmid-Scho¨nbein. "The Pressure-Flow Relation for Plasma in Whole Organ Skeletal Muscle and Its Experimental Verification." Journal of Biomechanical Engineering 113, no. 4 (November 1, 1991): 452–57. http://dx.doi.org/10.1115/1.2895426.
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The whole-organ pressure-flow relation in resting rat skeletal muscle is examined for the flow of plasma. Due to the small size of the blood vessels in this organ, inertia and convective forces in the blood are negligible and viscous forces dominate. Direct measurements in the past have shown that skeletal muscle blood vessels are distensible. Theoretical formulations based on these measurements lead to a third order polynomial model for the pressure-flow relation. The purpose of the current study is to examine this relation experimentally in an isolated muscle organ. A high precision feedback controlled pump is used to perfuse artificial plasma into the vasodilated rat gracilis muscle. The results indicate that the pressure-flow curve in this tissue is nonlinear in the low flow region and almost linear at physiological flow rates, following closely the third order polynomial function. Vessel fixation with glutaraldehyde causes the curves to become linear at all pressures, indicating that vessel distention is the primary mechanism causing the nonlinearity. Furthermore, the resistance of the post-fixed tissue is determined by the pressure at which the fixative is perfused. At fixation pressures below 10 mmHg, the resistance is three times higher than in vessels fixed at normal physiological pressures. Dextran (229,000 Dalton) is used to obtain Newtonian perfusates at different viscosities. The pressure-flow relation is found to be linearly dependent on viscosity for all flow rates. Skeletal muscle has multiple arterial inflows. Separate perfusion of the two major arterial feeders in the rat gracilis muscle show that for low pressures the flow at each feeder is dependent on the pressure at the opposite feeder, whereas at normal pressures the flow becomes independent of the opposite feeder pressure. The hemodynamic resistance in plasma perfused vasodilated skeletal muscle depends on vessel distensibility, plasma viscosity, and can be closely modeled by a third order polynomial relation.
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Updike, D. P., and A. Kalnins. "Tensile Plastic Instability of Axisymmetric Pressure Vessels." Journal of Pressure Vessel Technology 120, no. 1 (February 1, 1998): 6–11. http://dx.doi.org/10.1115/1.2841888.
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This paper examines the calculated pressure at a tensile plastic instability of a pressure vessel and its relationship to burst test results. It is proposed that the instability pressure be accepted as an upper bound to the pressure at which a vessel bursts, and that a strength reduction factor be used to predict the burst. The paper also presents a suitable mathematical model for the calculation of the instability pressures for thin-walled axisymmetric vessels. The proposition is tested by applying the model to a pressurized diaphragm, four cylindrical shells, and two torispherical heads, for which experimental burst data are available. It is found that the ratio of the test burst pressure to the calculated pressure at the tensile plastic instability, expressed in percent, ranges from 71 to 96 percent. The highest ratio occurs for a pressurized diaphragm with no significant defects. The lowest ratios occur for cylindrical shells with longitudinal welds, suggesting that the presence of the welds had a detrimental effect on the burst strength. These results may be useful when designing a pressure vessel with respect to its ultimate strength.
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Nellis, S. H., and L. Whitesell. "Phasic pressures and diameters in small epicardial veins of the unrestrained heart." American Journal of Physiology-Heart and Circulatory Physiology 257, no. 4 (October 1, 1989): H1056—H1061. http://dx.doi.org/10.1152/ajpheart.1989.257.4.h1056.
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Previous data from this laboratory have revealed a large pressure pulse in small veins on the epicardial surface of the right ventricle of the rabbit. The phasic relationship between venule pressures and venule diameters in a beating heart was examined. Luminal pressures were measured in 39 different veins on the epicardial surface of the rabbit right ventricle. The venous luminal pressures averaged 12.6 mmHg maximum and 1.0 mmHg minimum. Pressures in 23 different small veins were also obtained at different right ventricular afterloads. Peak venous pressures increased with peak right ventricular pressure. The phasic diameter changes of 119 different vessels were examined. Vessel diameters decreased as luminal pressures increased. The average change in vessel diameter through a cardiac cycle was 20%, with a range from 0 to 60%. The large pulse pressures found in small veins appear to be related to decreasing vessel diameters and probably result from the displacement of blood as the vessels narrow.
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Islamović, Fadil, Mirzet Beganović, Esad Bajramović, and Dženana Gačo. "Application of mathematical modelling in the process of design and production of pressure vessels." IOP Conference Series: Materials Science and Engineering 1208, no. 1 (November 1, 2021): 012006. http://dx.doi.org/10.1088/1757-899x/1208/1/012006.
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Abstract The paper presents the engineering practice, which the company “Regeneracija” Ltd. Velika Kladuša – Bosnia and Herzegovina uses to perform preliminary experimental testing and measurements, followed by mathematical modeling of critical pressure of these vessels, in order to obtain the projected quality of pressure vessels made of composite materials. The paper will confirm the hypothesis that it is possible to relate mathematical connection and dependence of the critical pressure of vessels of composite materials (Pkr) with mechanical characteristics of vessel material (σM), vessel diameter (D), and vessel wall thickness (s). In this way, by varying the mentioned parameters, it is possible to achieve the desired product quality in the production of composite material containers by achieving the projected critical and thus working pressure. Generally speaking, the mathematical model of critical pressure obtained in this way will be a good indicator for design engineers to know how much critical pressure a given vessel can withstand, and based on that to take quick control of working or projected pressure, but also for designing completely new vessels made of composite materials as a substitute for the expensive experimental testing.
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Song, Yan Dong. "Design Research on Pressure Vessel of Automobiles Assembly Shop." Applied Mechanics and Materials 508 (January 2014): 204–7. http://dx.doi.org/10.4028/www.scientific.net/amm.508.204.
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In the same conditions, the accidents of pressure vessel are much higher than other mechanical equipment. Therefore, the study on the pressure vessels in anomaly conditions and the dynamic response and tolerance capabilities of the structure not only helps to the research and development of warning surveillance and prevention technology about pressure vessels in anomaly conditions, but also contribute to the correct evaluation of the feasibility and reliability on the device of early warning monitoring system and the prevent technology. As pressure vessel is widely used and efficiency is enhanced, traditional failure analysis is restricted to test, analyze accidents, find out failure reasons and table proposals. It is realistic to make a modern design system for pressure vessels, judge failure reasons rapidly and table proposals. Keywords: pressure vessel; modern design; working characteristics
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Davis, Michael J., Elaheh Rahbar, Anatoliy A. Gashev, David C. Zawieja, and James E. Moore. "Determinants of valve gating in collecting lymphatic vessels from rat mesentery." American Journal of Physiology-Heart and Circulatory Physiology 301, no. 1 (July 2011): H48—H60. http://dx.doi.org/10.1152/ajpheart.00133.2011.
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Secondary lymphatic valves are essential for minimizing backflow of lymph and are presumed to gate passively according to the instantaneous trans-valve pressure gradient. We hypothesized that valve gating is also modulated by vessel distention, which could alter leaflet stiffness and coaptation. To test this hypothesis, we devised protocols to measure the small pressure gradients required to open or close lymphatic valves and determine if the gradients varied as a function of vessel diameter. Lymphatic vessels were isolated from rat mesentery, cannulated, and pressurized using a servo-control system. Detection of valve leaflet position simultaneously with diameter and intraluminal pressure changes in two-valve segments revealed the detailed temporal relationships between these parameters during the lymphatic contraction cycle. The timing of valve movements was similar to that of cardiac valves, but only when lymphatic vessel afterload was elevated. The pressure gradients required to open or close a valve were determined in one-valve segments during slow, ramp-wise pressure elevation, either from the input or output side of the valve. Tests were conducted over a wide range of baseline pressures (and thus diameters) in passive vessels as well as in vessels with two levels of imposed tone. Surprisingly, the pressure gradient required for valve closure varied >20-fold (0.1–2.2 cmH2O) as a passive vessel progressively distended. Similarly, the pressure gradient required for valve opening varied sixfold with vessel distention. Finally, our functional evidence supports the concept that lymphatic muscle tone exerts an indirect effect on valve gating.
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Nurdin, R., and R. Sriwijaya. "Effect of Pad Thickness and Width Variations on Plastic Limit Moment in Cylindrical Pressure Vessels Due to Nozzle In-Plane Load." Journal of Physics: Conference Series 2739, no. 1 (April 1, 2024): 012026. http://dx.doi.org/10.1088/1742-6596/2739/1/012026.
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Abstract This study investigates how different pad thicknesses and diameters affect the maximum stress a cylindrical pressure vessel can handle without failing, particularly around the areas where nozzles are attached. Nozzles on these vessels often face directional stress from loads applied in a specific plane, and these stresses mustn’t push the nozzle material beyond its breaking point. The research used computer simulations to see how these vessels, with various pad sizes and a set shell and nozzle size, behave under increasing stress until they reach their breaking point. Findings indicate that making the pad thicker or wider increases the vessel’s resistance to breaking up to a certain point; beyond this optimal size, making the pad larger doesn’t provide any additional benefit. This information helps design better and safer pressure vessels by identifying the best pad size to prevent failure. The study contributes to understanding how to avoid design issues and optimize the construction of these vessels, adhering to specific industry standards.
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Drzewiecki, Gary, Shawn Field, Issam Moubarak, and John K. J. Li. "Vessel growth and collapsible pressure-area relationship." American Journal of Physiology-Heart and Circulatory Physiology 273, no. 4 (October 1, 1997): H2030—H2043. http://dx.doi.org/10.1152/ajpheart.1997.273.4.h2030.
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The role that the pattern of vessel wall growth plays in determining pressure-lumen area (P-A) and pressure-compliance curves was examined. A P-A vessel model was developed that encompasses the complete range of pressure, including negative values, and accounts for size given the fixed length, nonlinear elastic wall properties, constant wall area, and collapse. Data were obtained from excised canine carotid and femoral arteries, jugular veins, and elastic tubing. The mean error of estimate was 8 mmHg for all vessels studied and 2 mmHg for blood vessels. The P-A model was employed to examine two patterns of arterial wall thickening, outward growth and remodeling (constant wall area), under the assumption of constant wall properties. The model predicted that only outward wall growth resets compliance such that it increases at a given arterial pressure, explaining previously contradictory data. In addition, it was found that outward wall growth increases the lumen area between normal and high pressures. Remodeling resulted in lumen narrowing and a decrease in compliance for positive pressures.
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Joubert-Huebner, E., A. Gerdes, and H.-H. Sievers. "An in vitro evaluation of a new cannula tip design compared with two clinically established cannula-tip designs regarding aortic arch vessel perfusion characteristics." Perfusion 15, no. 1 (January 2000): 69–76. http://dx.doi.org/10.1177/026765910001500110.
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We investigated in vitro aortic arch vessel perfusion characteristics of single and multiple jet-stream cannulae and a new dispersion stream tip aortic cannula. Pressures and flows of all arch vessels were measured while directing cannulae jets at the different arch vessels using 6 l/min pump flow. The highest increase in pressure above the set systemic level of 80 mmHg and increase in flow above the set normal flow distribution in the arch vessels occurred in the jet-streamed arch vessels with the single stream cannula. The values were as follows: 29 mmHg and 118 ml/min for the innominate artery, 28 mmHg and 42 ml/min for the left common carotid artery, and 25 mmHg and 54 ml/min for the left subclavian artery. The dispersion stream cannula showed increases in pressure and flow, followed by the multiple stream cannula. Aortic cannula tips and the orientation of jets are potential sources of imbalances of arch vessel perfusion with possible clinical implications regarding perfusion of arch vessels during extracorporeal circulation.
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Yan, Chen, Zhirong Wang, Kai Liu, Qingqing Zuo, Yaya Zhen, and Shangfeng Zhang. "Numerical simulation of size effects of gas explosions in spherical vessels." SIMULATION 93, no. 8 (March 20, 2017): 695–705. http://dx.doi.org/10.1177/0037549717698227.
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To study the law of sizes on gas explosions, numerical simulations of methane–air mixture explosions in spherical vessels were performed. The law of sizes on gas explosions is studied using FLUENT simulations with the [Formula: see text] two-equation turbulent model, the eddy-dissipation-concept model, thermal dissipation at a wall boundary, the P1 model, and the SIMPLE algorithm. The experimental results suggest that under an adiabatic condition without energy loss, the maximum explosion pressures in different spherical vessels are all 0.82 MPa, and the effect on the explosion intensity in spherical vessels is small. Under the condition of heat dissipation at the wall boundary, the maximum explosion pressure increases with volume of the spherical vessel. However, the explosion intensity in this condition is lower than that in adiabatic condition. Also, the size effect is not obvious. The size effect on the explosion intensity is significant under the combined effects of heat dissipation at the wall boundary and thermal radiation, where the maximum explosion pressure increases with volume of spherical vessels. On the contrary, the maximum pressure rising rate decreases with the volume of the spherical vessels; this rule coincides with the “cube” law. The studies on the size effects of methane–air mixture explosions in a spherical vessel provide an important reference for establishing a model system that can be used to test and design industrial vessels.
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vom Hofe, Burkhardt, Anika Pehl, Detlef Bartsch, and Andreas Kirschbaum. "Double Bipolar Sealing of the Pulmonary Artery Improves the Bursting Pressures." Thoracic and Cardiovascular Surgeon 65, no. 05 (December 15, 2015): 351–55. http://dx.doi.org/10.1055/s-0035-1570022.
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Background In every anatomic lung resection, branches of the pulmonary artery have to be divided. In open surgery, this can be done with ligatures or staplers. In endoscopic surgery, only an endostapler can be used. By routing we ligate the vessels double. Bipolar sealing had yielded promising results, so we wanted to know if we can improve the bursting pressures especially in case of larger vessels by double sealing. Methods Experiments were performed on preparations of the left pulmonary artery extracted at the slaughterhouse. A pressure sensor was implanted at the central end to provide digital measurement of the pneumatic load on the vessel seal and thus establish bursting pressure in each case. Vessels were sealed with MARSEAL 5 (Gebrüder Martin GmbH & Co KG, Tuttlingen, Germany) and SealSafe G3 electric current. The vessels investigated were separated into three sizes: 1 to 6 mm, 7 to 12 mm, and >12 mm. The groups (n = 12 in each) were investigated for each vessel size—Group 1: ligature; Group 2: single seal; Group 3: double seals separated by gap of 0.5 cm; and Group 4: double seals separated by gap of 1.0 cm. Mean bursting pressure (mbar) was calculated for each group. Differences between groups were calculated with Mann–Whitney U test; differences with p < 0.05 were considered significant. Results The ligated vessels in the 1 to 6 mm group showed the highest bursting pressures (mean 515.7 ± 39.6 mbar). Mean bursting pressure in the single seal group was 231.6 ± 47.5 mbar. This was not significantly different from the group with double seals placed 0.5 cm apart. However, bursting pressures were significantly higher in the group with double seals placed 1 cm apart (p < 0.001). Mean value in this case was 308.5 ± 44.5 mbar. In the 7 to 12 mm vessels, mean bursting pressure was highest with ligation at 361 ± 67.1 mbar but was significantly higher in both groups with double bipolar seals (180.3 ± 52.1 mbar with 0.5-cm separation and 277.0 ± 64.5 with 1-cm separation) than in the single seal group (102.7 ± 16.1 mbar). In large vessels (>12 mm), mean bursting pressures were low (66.3 ± 12.7 mbar) with single seals but were significantly higher with double seals (162.3 ± 35.8 mbar [0.5-cm separation] and 137.3 ± 22.9 mbar [1-cm separation]). Conclusions In the ex vivo model of the pulmonary artery, double seals revealed significantly higher bursting pressures than single seals. If there is enough vessel length, the two seals should be placed 1 cm apart.
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Dawson, C. A., D. A. Rickaby, and J. H. Linehan. "Location and mechanisms of pulmonary vascular volume changes." Journal of Applied Physiology 60, no. 2 (February 1, 1986): 402–9. http://dx.doi.org/10.1152/jappl.1986.60.2.402.
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We examined the influence of changing outflow pressure, P out, on the vascular and extravascular volumes (QV and QEV, respectively, as measured by indicator dilution) and on the outflow occlusion pressures in isolated dog lung lobes perfused with constant flow. Changing P out had a substantial effect on QV, but not on QEV, whether P out was less than or greater than alveolar pressure, PA. Since QEV did not change with QV, recruitment of previously unperfused vessels did not appear to contribute substantially to the increases in QV when P out was increased. The rapid jump in P out immediately following outflow occlusion was virtually independent of the difference between PA and P out suggesting that the alveolar vessels were an important volume storage site when P out was low relative to PA. We conclude that, over a certain range of pressures, alveolar vessel volume can be controlled by venous pressure even when the change in venous pressure has little effect on arterial pressure (zone 2). Further, we conclude that in zone 3 and within the transition from zone 2 to zone 3 increases in the intralobar blood volume occurring within the alveolar vessels may not require recruitment in the sense of opening of previously unperfused vessels.
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K, Abhinash. "DESIGN AND ANALYSIS OF PRESSURE VESSEL USING DIFFERENT MATERIALS." INTERANTIONAL JOURNAL OF SCIENTIFIC RESEARCH IN ENGINEERING AND MANAGEMENT 08, no. 05 (May 5, 2024): 1–5. http://dx.doi.org/10.55041/ijsrem32962.
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This project explores the field of Finite Element Analysis (FEA) in relation to pressure vessels that have different head configurations, while ensuring that the cylindrical volume and thickness remain uniform. The project adheres to ASME standards, specifically Section VIII, Division I, and focuses on designing a pressure vessel that can withstand a pressure of 8 bar within a volume of 24 liters. The main objective of using FEA is to identify areas of stress concentration in each head design. In industrial settings, pressure vessels play a crucial role in containing fluids or gases under varying pressures. The choice of head configuration significantly impacts the distribution of stress and the overall structural strength. This project specifically utilizes ANSYS software for static and thermal analyses to compare stress distribution in pressure vessels with flat heads, elliptical heads, and other common head designs. The goal is to identify configurations that exhibit lower stress levels, with a particular emphasis on practical scenarios that favor elliptical heads. Additionally, the project explores finite element modeling techniques to evaluate pressure vessels made from different materials such as Nimonic 80A and SA516 Gr70 under high-stress conditions
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Dalton, M., and M. Sabbaghian. "Creep Relaxation in Multilayer Wrapped Vessels." Journal of Pressure Vessel Technology 109, no. 4 (November 1, 1987): 464–68. http://dx.doi.org/10.1115/1.3264932.
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One of the common methods of construction of vessels for high to ultra-high pressure applications is the wrapping technique. In this method, relatively thin plates (normally in the range of 6 mm) are rolled to proper curvature, wrapped around the core or the preceding layers and then welded. In this fashion, a prestress is gradually built in the cylinder wall which would compensate and moderate the extreme stresses due to internal pressure. Relying on such prestress, however, should be done only with careful consideration of stress relaxation that will take place while the vessel is in service, especially in high temperature services. In this paper, the initial stresses due to wrapping are obtained. These stresses are due to shrinkage of the weld as well as the plate affected by the heat of welding. The power function stress-creep strain rate is employed to predict the relaxation of interface pressure between any two adjacent layers. The creep stress distribution based on relaxing interface pressures are given as a function of time. In such vessels, in order to maintain the same safety factor as existed when the vessel was constructed, the internal pressure must be decreased with time. A relationship between the internal pressure and time, based on a constant safety factor, is obtained. Alternately, for the case of internal pressure being kept at the same level, a relationship is obtained that would give the decreasing safety factor or the vessel as a function of time.
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Xiao, Biao, Bin Yang, Fu-Zhen Xuan, Yun Wan, Chaojie Hu, Pengcheng Jin, Hongshuai Lei, Yanxun Xiang, and Kang Yang. "In-Situ Monitoring of a Filament Wound Pressure Vessel by the MWCNT Sensor under Hydraulic Fatigue Cycling and Pressurization." Sensors 19, no. 6 (March 21, 2019): 1396. http://dx.doi.org/10.3390/s19061396.
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As a result of the high specific strength/stiffness to mass ratio, filament wound composite pressure vessels are extensively used to contain gas or fluid under pressure. The ability to in-situ monitor the composite pressure vessels for possible damage is important for high-pressure medium storage industries. This paper describes an in-situ monitoring method to permanently monitor composite pressure vessels for their structural integrity. The sensor is made of a multi-walled carbon nanotube (MWCNT) that can be embedded in the composite skin of the pressure vessels. The sensing ability of the sensor is firstly evaluated in various mechanical tests, and in-situ monitoring experiments of a full-scale composite pressure vessel during hydraulic fatigue cycling and pressurization are performed. The monitoring results of the MWCNT sensor are compared with the strains measured by the strain gauges. The results show that the measured signal by the developed sensor matches the mechanical behavior of the composite laminates under various load conditions. In the hydraulic fatigue test, the relationship between the resistance and the strain is built, and could be used to quantitative monitor the filament wound pressure vessel. The bursting of the pressure vessel can be detected by the sharp increase of the MWCNT sensor resistance. Embedding the MWCNT sensor into the composite pressure vessel is successfully demonstrated as a promising method for structural health monitoring.
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Itoh, G. "Weld Investigation of Nuclear Power Plant Pressure Vessels." Journal of Pressure Vessel Technology 109, no. 2 (May 1, 1987): 224–27. http://dx.doi.org/10.1115/1.3264900.
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Welds in nuclear power plant pressure vessels, which were in accordance with the ASME Boiler and Pressure Vessel Code, though not with some other codes, were investigated nondestructively over a long period of service. The results indicate that the vessels have been operating for many years, with large slag inclusions that do not extend to the weld surfaces, causing no damage to the vessels. Hence, the practical relaxation of excessively conservative acceptance standards is discussed.
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Parazynski, S. E., B. J. Tucker, M. Aratow, A. Crenshaw, and A. R. Hargens. "Direct measurement of capillary blood pressure in the human lip." Journal of Applied Physiology 74, no. 2 (February 1, 1993): 946–50. http://dx.doi.org/10.1152/jappl.1993.74.2.946.
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In this study, we developed and tested a new procedure for measuring microcirculatory blood pressures above heart level in humans. Capillary and postcapillary venule blood pressures were measured directly in 13 human subjects by use of the servo-nulling micropressure technique adapted for micropuncture of lip capillaries. Pressure waveforms were recorded in 40 separate capillary vessels and 14 separate postcapillary venules over periods ranging from 5 to 64 s. Localization and determination of capillary and postcapillary vessels were ascertained anatomically before pressure measurements. Capillary pressure was 33.2 +/- 1.5 (SE) mmHg in lips of subjects seated upright. Repeated micropunctures of the same vessel gave an average coefficient of variation of 0.072. Postcapillary venule pressure was 18.9 +/- 1.6 mmHg. This procedure produces a direct and reproducible means of measuring microvascular blood pressures in a vascular bed above heart level in humans.
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Underwood, John H., David B. Moak, Michael J. Audino, and Anthony P. Parker. "Yield Pressure Measurements and Analysis for Autofrettaged Cannons." Journal of Pressure Vessel Technology 125, no. 1 (January 31, 2003): 7–10. http://dx.doi.org/10.1115/1.1526857.
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Yield pressure corresponding to a small permanent OD strain was measured in quasi-static laboratory tests of autofrettaged ASTM A723 steel cannon pressure vessels. Yield pressure was found to be a consistent ratio of the yield strength measured from specimens located in close proximity to the area of observed yielding. Yield pressure measurements for dynamic cannon firing with typically a 5-ms pressure pulse duration gave 14% higher yield pressures, attributed to strain rate effects on plastic deformation. Calculated Von Mises yield pressure for the laboratory test conditions, including the Bauschinger-modified ID residual stress and open-end vessel conditions, agreed with measured yield pressure within 3–5%. Calculated yield pressure was found to be insensitive to the value of axial residual stress, since axial stress is the intermediate value in the Von Mises yield criterion. A description of yield pressure normalized by yield strength was given for autofrettaged A723 open-end pressure vessels over a range of wall ratio and degree of autofrettage, including effects of Bauschinger-modified residual stress. This description of yield pressure is proposed as a design procedure for cannons and other pressure vessels.
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Yu, Shao Rong, Yi Hui Yin, Xu Bing, and Jun Mei. "Influences of Long-Period Hydrogen Storage on Structural Performance of Steel Vessel." Advanced Materials Research 230-232 (May 2011): 1089–92. http://dx.doi.org/10.4028/www.scientific.net/amr.230-232.1089.
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Presently, there are a significant number of investigations that study the influences of the hydrogen embrittlement on pressure vessels for hydrogen storage. But few of them consider the effects of helium-3 decayed from hydrogen. This paper studies the effects of the high-pressure hydrogen on mechanical behavior of a kind of steel pressure vessel by elastic-plastic finite element simulations, based on the explosion tests data of 4-, 6-, 14- and 17-year hydrogen storage vessels and relating experimental data of materials properties. Then the mechanical responses of the 50-year hydrogen storage pressure vessel are predicted. The results provide guidelines for design and evaluating hydrogen storage vessels.
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Nebe, Martin, Daniel Maraite, Clemens Braun, Daniel Hülsbusch, and Frank Walther. "Experimental Characterization of the Structural Deformation of Type IV Pressure Vessels Subjected to Internal Pressure." Key Engineering Materials 809 (June 2019): 47–52. http://dx.doi.org/10.4028/www.scientific.net/kem.809.47.
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The investigations deal with the experimental characterization of the structural deformation of type IV pressure vessels subjected to internal pressure. For the widespread use of hydrogen technology in transport industries, the development of cost-effective storage systems is a crucial step. State of the art in the field of hydrogen storage are type IV pressure vessels, which consist of a polymeric liner and an enforcing winding of carbon fiber-reinforced plastic (CFRP). For the development of material-optimized and high-safety pressure vessels, the acquisition of reliable experimental data in order to validate numerical simulations is a necessity. In a specially designed test chamber subscale vessels are clamped and subjected to internal pressure. At defined pressure stages the vessel’s deformation is recorded and analyzed. Consequently, the overall structural deformation is assessed with regard to the used structural mass, the burst pressure and the resulting failure. The results can be used for structure optimization purposes as well as for the optimization of numerical simulation models.
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Dalton, J. A., and F. G. F. Gibb. "Temperature gradients in large cold-seal pressure vessels." Mineralogical Magazine 60, no. 399 (April 1996): 337–45. http://dx.doi.org/10.1180/minmag.1996.060.399.08.
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AbstractRadial and longitudinal temperature gradients within cold-seal pressure vessels can contribute significantly to the total temperature unccrtainty in any one experiment and it is important to calibrate such gradients before experiments are undertaken. We have measured temperature gradients in vertically mounted large cold-seal vessels at 1 atm and 1 kbar and in the temperature range 500–800°C Radial gradients were measured with the vessel at various positions within the furnace by recording the temperature difference between a thermocouple in the internal bore of the vessel and one in a well in the top of the vessel. We find that when the vessel is at a certain position in the furnace, the temperatures read by these two thermocouples are equivalent to within 1°C. The contribution of radial gradients to temperature uncertainty can be thus be substantially minimized if experiments are undertaken with the vessel in this position. Longitudinal gradients of 2.8°C/cm at 500°C and 3°C/cm at 800°C were recorded at 1 kbar. These profiles are significantly steeper than those recorded at 1 atm. Not to calibrate temperature gradients at the experimental conditions or failure to calibrate vessels at all could lead to large temperature uncertainties.
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Bi, Yao, Hongliang Zhou, Zhiyao Huang, Hanhua Zhou, and Xianglong Yang. "Ultrasonic pressure measurement in pressure vessels." Review of Scientific Instruments 85, no. 12 (December 2014): 125002. http://dx.doi.org/10.1063/1.4902338.
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Wang, Mingtao, Melvin T. Tyree, and Roderick E. Wasylishen. "Magnetic resonance imaging of water ascent in embolized xylem vessels of grapevine stem segments." Canadian Journal of Plant Science 93, no. 5 (September 2013): 879–93. http://dx.doi.org/10.4141/cjps2013-025.
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Wang, M., Tyree, M. T. and Wasylishen, R. E. 2013. Magnetic resonance imaging of water ascent in embolized xylem vessels of grapevine stem segments. Can. J. Plant Sci. 93: 879–893. Temporal and spatial information about water refilling of embolized xylem vessels and the rate of water ascent in these vessels is critical for understanding embolism repair in intact living vascular plants. High-resolution 1H magnetic resonance imaging (MRI) experiments have been performed on embolized grapevine stem segments while they were subjected to refilling at two different applied water pressures in order to investigate these important aspects of embolism repair. Magnetic resonance imaging difference images show that vessels located near the bark tend to refill faster than do inner ones, suggesting that vessel position within the cross section of the stem may affect the refilling process within the vessel. An MRI method for determining the water ascent velocity in each individual embolized xylem vessel is presented. At ambient pressure, the water ascent velocity ranges from 0.0090 to 0.60 mm min−1, but increases to a range of 0.016 to 0.70 mm min−1 at 9.8 kPa above ambient pressure. A steady-state bubble model that offers analytical solutions of the water ascent velocity in embolized xylem vessels is presented; model calculations show that if other parameters are held constant, water ascent velocity is influenced by vessel diameter and position.
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Chavda, Bhavik, Rupak Shukla, Harshit Tiwari, Ashutosh Pandey, and Yusuf Rehman. "Design of Pressure Vessel Using Computational Techniques." International Journal for Research in Applied Science and Engineering Technology 10, no. 3 (March 31, 2022): 2247–57. http://dx.doi.org/10.22214/ijraset.2022.41116.
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Abstract: This paper discusses some of the recent advances in determining the stress concentration factor in pressure vessels at openings, stress analysis of various types of end connections, and stress minimization by optimizing the location and angle of the nozzle on the shell and head. The area of stress concentration analysis in pressure vessels is gaining popularity, according to the literature. The goal of this study is to look at the stress concentrations that occur at the openings of pressure vessels and how to mitigate their effects. The ASME pressure vessel code governs the design of pressure vessels. The code specifies the thickness and stress of fundamental components; it is up to the designer to determine stress due to other loadings using an appropriate analytical approach. Recent and previous developments, theories for stress concentration estimate, and the possibilities for future investigations are all discussed in this study. We'll also use data analysis software like Solidworks to computationally assess our design. Also, technologies like Excel were considered for creating our design's data sheet, and they were coupled with Solidworks software for a speedy outcome. This strategy will not only save time but will also save money if used on a large basis. The project's main goals and objectives are as follows: Design the pressure vessel following the ASME (American Society of Mechanical Engineers) code. Create a Solidworks 3D model of a pressure vessel. Using Solidworks software, analyze the stiffness and strength of pressure vessel material and design. To improve the facility, staff, and public safety. To use simulation tools to check the design's accuracy. To ensure computation repeatability by using EXCEL as the design calculation method. To make all design methods more efficient in terms of time. To enhance public and personal security. Keywords: Pressure Vessel, Solidworks, Design, Excel, Etc.
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Mohan, A., and T. Christopher. "Elasto-Plastic Stress Analysis of Thick Cylinders." Advanced Materials Research 984-985 (July 2014): 456–63. http://dx.doi.org/10.4028/www.scientific.net/amr.984-985.456.
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–Pressure vessels often have a combination of high pressure together with high temperature such as gun barrels and high pressure hydraulic rams. For high pressure application, the cylindrical vessels are made to withstand the working pressure. These types of pressure vessels are made by two techniques, one is shrink-fit cylinders and other one is autofrettage cylinders. Autofrettage technique is used to ensure the pressure vessel highly strengthened due to prestressed effect causing the internal portion of the part to yield and resulting in internal compressive residual stresses. The present work is concerned about the elastoplastic stress analysis of thick cylinders. The numerical analysis is carried out on four different materials which are widely used in pressure vessels by using finite element software ANSYS. The elastic breakdown pressure, overstrain pressure, and bursting pressure of the cylinder are found out and the results are compared with experimental results.
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Kangal, Serkan, Osman Kartav, Metin Tanoğlu, Engin Aktaş, and H. Seçil Artem. "Investigation of interlayer hybridization effect on burst pressure performance of composite overwrapped pressure vessels with load-sharing metallic liner." Journal of Composite Materials 54, no. 7 (August 27, 2019): 961–80. http://dx.doi.org/10.1177/0021998319870588.
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In this study, multi-layered composite overwrapped pressure vessels for high-pressure gaseous storage were designed, modeled by finite element method and manufactured by filament winding technique. 34CrMo4 steel was selected as a load-sharing metallic liner. Glass and carbon filaments were overwrapped on the liner with a winding angle of [±11°/90°2]3 to obtain fully overwrapped composite reinforced vessel with non-identical front and back dome endings. The vessels were loaded with increasing internal pressure up to the burst pressure level. The mechanical performances of pressure vessels, (i) fully overwrapped with glass fibers and (ii) with additional two carbon hoop layers on the cylindrical section, were investigated by both experimental and numerical approaches. In numerical approaches, finite element analysis was performed featuring a simple progressive damage model available in ANSYS software package for the composite section. The metal liner was modeled as elastic–plastic material. The results reveal that the finite element model provides a good correlation between experimental and numerical strain results for the vessels, together with the indication of the positive effect on radial deformation of the COPVs due to the composite interlayer hybridization. The constructed model was also able to predict experimental burst pressures within a range of 8%. However, the experimental and finite element analysis results showed that hybridization of hoop layers did not have any significant impact on the burst pressure performance of the vessels. This finding was attributed to the change of load-sharing capacity of composite layers due to the stiffness difference of carbon and glass fibers.
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Ye, Linghe, and Lin Lu. "Environmental and economic evaluation of the high-pressured and cryogenic vessels for hydrogen storage on the sedan." International Journal of Low-Carbon Technologies 18 (2023): 144–49. http://dx.doi.org/10.1093/ijlct/ctac126.
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Abstract This paper carried out the environmental and economic evaluation for the hydrogen storage technologies on the sedan with Type 3 and Type 4 high-pressured and cryogenic vessels based on life cycle analysis (LCA) method. It is found that Type 4 high-pressured vessel manufacture emits minimum greenhouse gas (GHG) with 5539 kgCO2 eq, which is lower than Type 3 high-pressured vessel of 7219 kgCO2 eq and cryogenic vessel of 135 000 kgCO2 eq in their whole life cycle. The economic analysis shows that Type 4 high-pressure vessel has the lowest cost of 10.4 US$/kgH2 and the minimum energy consumption of 5.2 kWh/kgH2, which is lower than Type 3 high-pressure vessel and cryogenic vessel. With this result, Type 4 high-pressure vessel is a promising choice for hydrogen mobility on the sedan regarding its environmental impact and economic performance.
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Du, Yannan, Xuchen Zhu, Bin Ren, and Xiaoying Tang. "Annual inspection of pressure vessel." E3S Web of Conferences 245 (2021): 03075. http://dx.doi.org/10.1051/e3sconf/202124503075.
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This paper systematically discusses the significance of pressure vessel inspection, defines the main body of annual inspection of pressure vessel, and puts forward the matters needing attention in the process of annual inspection according to the existing annual inspection situation, so as to provide a certain reference for the smooth development of annual inspection of pressure vessels.