Journal articles: 'Pressure calculation'

1

Hao, Shouzhi, and Jian Su. "Basic Snow Pressure Calculation." IOP Conference Series: Materials Science and Engineering 317 (March 2018): 012018. http://dx.doi.org/10.1088/1757-899x/317/1/012018.

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Hall, J. R., and R. G. Brouillard. "Water vapor pressure calculation." Journal of Applied Physiology 58, no. 6 (June 1, 1985): 2090. http://dx.doi.org/10.1152/jappl.1985.58.6.2090.

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Accurate calculation of water vapor pressure for systems saturated with water vapor can be performed using the Goff-Gratch equation. A form of the equation that can be adapted for computer programming and for use in electronic databases is provided.

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Belyaev, Aleksandr V., Alexey V. Dedov, Ilya I. Krapivin, Aleksander N. Varava, Peixue Jiang, and Ruina Xu. "Study of Pressure Drops and Heat Transfer of Nonequilibrial Two-Phase Flows." Water 13, no. 16 (August 20, 2021): 2275. http://dx.doi.org/10.3390/w13162275.

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Currently, there are no universal methods for calculating the heat transfer and pressure drop for a wide range of two-phase flow parameters in mini-channels due to changes in the void fraction and flow regime. Many experimental studies have been carried out, and narrow-range calculation methods have been developed. With increasing pressure, it becomes possible to expand the range of parameters for applying reliable calculation methods as a result of changes in the flow regime. This paper provides an overview of methods for calculating the pressure drops and heat transfer of two-phase flows in small-diameter channels and presents a comparison of calculation methods. For conditions of high reduced pressures pr = p/pcr ≈ 0.4 ÷ 0.6, the results of own experimental studies of pressure drops and flow boiling heat transfer of freons in the region of low and high mass flow rates (G = 200–2000 kg/m2 s) are presented. A description of the experimental stand is given, and a comparison of own experimental data with those obtained using the most reliable calculated relations is carried out.

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Orr, T. LL, and C. Cherubini. "Use of the ranking distance as an index for assessing the accuracy and precision of equations for the bearing capacity of piles and at-rest earth pressure coefficient." Canadian Geotechnical Journal 40, no. 6 (December 1, 2003): 1200–1207. http://dx.doi.org/10.1139/t03-063.

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In many geotechnical design situations, a number of different calculation models have been developed to predict the value of a particular quantity required for use in design calculations, for example, the bearing capacities of driven and root piles, and K0, the at-rest earth pressure coefficient. In this paper the authors show how the dependability of different calculation methods can be compared and assessed using a synthetic probabilistic approach and the ranking distance (RD) index. Measured values, Qmeas, are compared with calculated values, Qcalc, using the "bias factor," defined as the ratio Qmeas/Qcalc. The bias factor values obtained using a particular calculation method are processed to evaluate the "accuracy" and "precision" by calculating a central tendency and a variability statistical parameter, respectively, from the values. The RD index is a comprehensive statistical parameter for assessing the dependability of a particular calculation method and is based on the central tendency and variability. Using the ratios between calculated and measured bearing capacity and earth pressures values, the RD index is used to assess the accuracy and precision of the most frequently used pile driving formulae, two equations for the bearing capacity of root piles, and seven equations for the at-rest earth pressure coefficient.Key words: accuracy, precision, probabilistic approach, ranking distance.

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KOSICHENKO, YU М. "UNIVERSAL METHOD FOR CALCULATING WATER PERMEABILITY OF ANTIFILTRATION LININGS WITH POLYMER GEOMEMBRANES." Prirodoobustrojstvo, no. 4 (2020): 6–13. http://dx.doi.org/10.26897/1997-6011-2020-4-6-13.

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There is considered a method for calculating water permeability of the main types of channel linings using geosynthetic materials – concrete film and soil film with polymer geomembrane and geotextile. During a long-term operation of irrigation channels it is necessary to carry out a quantitative assessment of water permeability of the linings, the results of which find filtration losses and determine the calculated efficiency. Modern anti-filtration channel linings made of geosynthetic materials can provide a high technical efficiency and durability of the lining. Based on the previously obtained theoretical solutions through single damages, a universal method has been developed that can be used to calculate water permeability of the main types of linings using geomembranes (concrete fi lm and soil fi lm). There are given calculation schemes through soil film and concretefilm lining and calculation dependences for the main calculation cases in the presence of cracks and holes in the screen on a highly permeable base and taking into account the influence of the permeability of the underlying base. The influence of the base permeability is taken into account in the calculations by the piezometric pressure h1at the damage place of to the geomembrane screen which is a residual pressure between the lining and soil base. The residual pressure can have both a positive sign under the excess pressure and a negative sign under formation of vacuum pressure. The calculation formulasfor determining the piezo-metric pressure at the place of damage are found using the equation of continuity of the filtration flow passing through defects and damages of the lining. Based on the developed method for calculating water permeability an example of calculation is considered which indicates a high efficiency of linings using geomembranes (concrete film and soil film) and for the concrete lining the condition of efficiency is not fulfilled.

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Saito, Shigeru. "Pressure Loss Calculation Software-2002." JAPAN TAPPI JOURNAL 57, no. 3 (2003): 392–98. http://dx.doi.org/10.2524/jtappij.57.392.

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7

Mikhalev, M. A. "Hydraulic calculation of pressure pipes." Magazine of Civil Engineering 32, no. 6 (October 2012): 20–28. http://dx.doi.org/10.5862/mce.32.3.

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Luks, K. D., E. A. Turek, and L. E. Baker. "Calculation of Minimum Miscibility Pressure." SPE Reservoir Engineering 2, no. 04 (November 1, 1987): 501–6. http://dx.doi.org/10.2118/14929-pa.

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9

Wang, Yun, and Franklin M. Orr. "Calculation of minimum miscibility pressure." Journal of Petroleum Science and Engineering 27, no. 3-4 (September 2000): 151–64. http://dx.doi.org/10.1016/s0920-4105(00)00059-0.

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10

Oyama, Mark A., Jess A. Weidman, and Steven G. Cole. "Calculation of pressure half-time." Journal of Veterinary Cardiology 10, no. 1 (June 2008): 57–60. http://dx.doi.org/10.1016/j.jvc.2008.02.002.

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11

Peng, Ying, Jun Sheng Yang, Yan Hua Shen, and Jian Hua Liu. "Mechanical Calculation for Collapse Mechanism of Surrounding Rock on Shallow Tunnel." Applied Mechanics and Materials 580-583 (July 2014): 1148–52. http://dx.doi.org/10.4028/www.scientific.net/amm.580-583.1148.

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The upper bound method of limit analysis is used for surrounding pressure calculation of shallow tunnel. Two rigid-block translational collapse mechanisms are assumed for shallow tunnel and the corresponding formulas are deduced. The earth pressure of shallow tunnel has been transformed into a mathematic optimization problem, we can get optimization solutions for the surrounding rock pressure by corresponding calculating program. It is concluded that the upper bound method of limit analysis is a feasible approach for the determination of surrounding pressures on shallow tunnel.

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12

Aryassov, G., D. Gornostajev, and I. Penkov. "Calculation Method for Plates with Discrete Variable Thickness Under Uniform Loading or Hydrostatic Pressure." International Journal of Applied Mechanics and Engineering 23, no. 4 (November 1, 2018): 835–53. http://dx.doi.org/10.2478/ijame-2018-0046.

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Abstract The article proposes a new analytical method for the calculation of plates with constant and variable rigidity parameters. This method renders it possible to decrease the weight of the plates working under hydrostatic pressure by using variable thicknesses. Firs, a short overview of existing calculation methods and their results are compared. It is shown that all existing methods depend on boundary conditions. Then is given the theory of the proposed calculation method is described and calculations for plates with constant and variable thickness worked under uniformly loaded forces and hydrostatic pressure are made. The results are compared to the FEM calculations and experimental results obtained by a tensile test machine and special equipment. Calculation results obtained by the proposed analytical method and FEM results are very close. Deviations are not more than 11%. Deviations between theoretical calculations and experimental results depend on loading type and design of the test specimens but maximum values are not more than 17%. The proposed calculation method does not depend on the boundary conditions and can be used for plate calculations. Especially for plates with difficult design and complex loading.

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13

Prokofiev, A. S., R. S. Gubatyuk, A. F. Muzhichenko, and V. N. Baranovsky. "Calculation of two-layer billet of spherical bottoms for high-pressure vessels." Paton Welding Journal 2016, no. 8 (August 28, 2016): 49–53. http://dx.doi.org/10.15407/tpwj2016.08.09.

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14

Fialová, Simona, František Pochylý, and Dominik Šedivý. "A new form of equation for force determination based on Navier-Stokes equations." EPJ Web of Conferences 213 (2019): 02018. http://dx.doi.org/10.1051/epjconf/201921302018.

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This work is focused on calculating the force effects of an incompressible homogeneous liquid on a surface of a rigid or a flexible tube. An unsteady flow induced by differential pressure at the beginning and at the end of the tube is assumed. The pressure difference for the unsteady flow is determined experimentally. The mathematical model is based on modified Navier-Stokes equations. The unsteady term is modified in order to be able to use the Gauss-Ostrogradsky theorem to calculate the force. This method of solution will allow the calculation of the force by integration of the Navier-Stokes equations, which will help to refine and simplify the calculations. In the article, both methods of force calculation will be presented and compared both through the ANSYS FEA and CFD ANSYS Fluent solvers and by the integration of the Navier-Stokes equation. The calculation will not only respect the compliance of the tube but also its movement status.

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15

Johansson, L. "Numerical Simulation of Contact Pressure Evolution in Fretting." Journal of Tribology 116, no. 2 (April 1, 1994): 247–54. http://dx.doi.org/10.1115/1.2927205.

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In the present paper an algorithm for frictional contact between two elastic bodies is presented. The algorithm is applied to the calculation of the evolution of contact pressure between two elastic bodies when material is being removed by fretting. To this end Archard’s law of wear is implemented into the algorithm. It is noticed that the calculated pressures after a period of fretting differ considerably from the initial Hertz type pressures. Further, it is noted that numerical instabilities can occur in explicit type wear calculations, and a stability criterion is suggested.

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16

Xin, Xuan Rong, Long Long Shan, and Xin Cheng Liu. "An Experiential Calculation Method to Radial Extrusion Pressure by Floating-Die." Advanced Materials Research 328-330 (September 2011): 246–52. http://dx.doi.org/10.4028/www.scientific.net/amr.328-330.246.

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By analyzing the rheological behavior and stress to the metal in cross-axle during a radial extrusion with floating-die, establishing a computational model of rigid-perfectly plastic and the stressing model similar to the forward extrusion, and introducing a simple forward extrusion calculation into a complicated radial extrusion calculation, a new calculation for radial extrusion is proposed, then the axial clamping force on female-die and other load parameters are calculated. Through verifying the result by Deform-3D numerical simulation, the formula proposed in this paper is approved to be of a relatively small error and a high accuracy, which can be applied to various calculations of forward extrusion model.

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17

Andersen, Knut H., Colin G. Rawlings, Tom A. Lunne, and Trond H. By. "Estimation of hydraulic fracture pressure in clay." Canadian Geotechnical Journal 31, no. 6 (December 1, 1994): 817–28. http://dx.doi.org/10.1139/t94-099.

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For offshore drilling, and in particular when drilling from fixed platforms in deep waters, the mud pressure will be high compared with the hydraulic fracture pressure (i.e., the formation strength) close to the sea floor. The first casing (the conductor) should therefore be installed to a depth where the formation strength is sufficient to prevent hydraulic fracturing of the soil. The consequences of hydraulic fracture could be mud flowing into the formation and loss of mud circulation. This slows down the drilling and, in cases where large quantities of mud flow into the formations beneath the platform, may even threaten the integrity of the foundation soils and create a safety problem. A conservative approach with too deep conductor setting depths will, on the other hand, lead to high unnecessary costs. This paper presents a new approach for calculating hydraulic fracture pressures. The new calculation approach considers two important factors that are generally not covered by theories found in the literature: nonlinearity of the stress–strain properties of the soil, and pore-pressure changes in the soil due to changes in total normal stress and shearing of the soil. The stress–strain properties and the shear-induced pore pressure are determined from laboratory tests. The proposed calculation approach has been verified against a series of laboratory model hydraulic fracture tests and in situ hydraulic fracture tests carried out at numerous offshore sites. The paper also presents a rational approach to establish the maximum allowable drilling mud pressure in clay formations and recommends partial safety coefficients that depend upon the consequences of hydraulic fracture and the quality of the soil data. Key words : hydraulic fracture, boreholes, clay, conductor setting depth, model tests, in situ tests, calculations.

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18

IKEGUCHI, Takashi, Manabu MATSUMOTO, and Shinjiro UEDA. "Calculation of pressure distribution in accelerators." SHINKU 31, no. 5 (1988): 424–27. http://dx.doi.org/10.3131/jvsj.31.424.

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19

Noggle, Joseph H., and Robert H. Wood. "Calculation of vapor pressure using Mathematica." Journal of Chemical Education 69, no. 10 (October 1992): 810. http://dx.doi.org/10.1021/ed069p810.

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20

Wang, Yun, and Franklin M. Orr. "Analytical calculation of minimum miscibility pressure." Fluid Phase Equilibria 139, no. 1-2 (December 1997): 101–24. http://dx.doi.org/10.1016/s0378-3812(97)00179-9.

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21

Dewar, William K., Ya Hsueh, Trevor J. McDougall, and Dongliang Yuan. "Calculation of Pressure in Ocean Simulations." Journal of Physical Oceanography 28, no. 4 (April 1998): 577–88. http://dx.doi.org/10.1175/1520-0485(1998)028<0577:copios>2.0.co;2.

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22

Al-Jawad, Mohammed S. "Reverse Calculation of Pressure from Pseudopressure." Polymer-Plastics Technology and Engineering 36, no. 4 (July 1997): 501–11. http://dx.doi.org/10.1080/03602559708000639.

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23

da Silva, Antônio J. R., and L. M. Falicov. "Calculation of optical transitions inNiI2andCoI2under pressure." Physical Review B 45, no. 20 (May 15, 1992): 11511–17. http://dx.doi.org/10.1103/physrevb.45.11511.

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24

TANAKA, Naoyuki. "Calculation of Elliptical Hertz Contact Pressure." Transactions of the Japan Society of Mechanical Engineers Series C 65, no. 638 (1999): 4213–15. http://dx.doi.org/10.1299/kikaic.65.4213.

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25

Wang, Hong, Lei Liu, and Xiang Liu. "Discussion on the Calculation and Analytic Method of the Surrounding Rock of Tunnel on the ADINA." Advanced Materials Research 779-780 (September 2013): 680–84. http://dx.doi.org/10.4028/www.scientific.net/amr.779-780.680.

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Space of surrounding rock pressure is caused by underground excavation surrounding rock mass and the supporting force of deformation or destruction. Weight model, reduction weight model, tunnel specification and finite element model are four commonly surrounding rock pressure calculation methods. This paper put forward a more reasonable tunnel surrounding rock pressure calculation model by using the finite element analysis software, numerical simulation of tunnel excavation and comparison and analysis of the four calculations results.

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Zhang, Liang, Bin Zhang, Cong Liu, and Yixue Chen. "Evaluation of PWR pressure vessel fast neutron fluence benchmarks from NUREG/CR-6115 with ares transport code." Nuclear Technology and Radiation Protection 32, no. 3 (2017): 204–10. http://dx.doi.org/10.2298/ntrp1703204z.

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An accurate evaluation of PWR pressure vessel fast neutron fluence is essential to ensure pressure vessel integrity over the design lifetime. The discrete ordinates method is one of the main methods to treat such problems. In this paper, evaluations have been performed for three PWR benchmarks described in NUREG/CR-6115 using ARES transport code. The calculated results were compared to the reference values and a satisfactory agreement was obtained. In addition, the effects of SN numeric and source distribution modeling for pressure vessel fast neutron fluence calculation are investigated. Based on the fine enough grids adopted, the different spatial and angular discretization introduces derivations less than 3 %, and fix-up for negative scattering source causes no noticeable effects when calculating pressure vessel fast neutron fluence. However, the discrepancy of assembly-wise and pin-wise source modeling for peripheral assemblies reaches ~20 %, which indicates that pin-wise modeling for peripheral assemblies is essential. These results provide guidelines for pressure vessel fast neutron fluence calculation and demonstrate that the ARES transport code is capable of performing neutron transport calculations for evaluating PWR pressure vessel fast neutron fluence.

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Yang, Zhi Yong, Shun Hu Liu, Song Zhao, Jun Hu, and Zeng Chan Lu. "Study on Silo Pressure by Consider Storage Materials Density Changed along the Height." Key Engineering Materials 517 (June 2012): 797–800. http://dx.doi.org/10.4028/www.scientific.net/kem.517.797.

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The difference existed between results of silos pressure calculation and the actual case, because the influence of density stratification was not taken into consideration. The aim of this paper was to obtain silo pressure calculating formula by consider of storage materials density stratified. To this end, we assume that the density was continuous changed along the height and differential equation of the storage materials pressure was established. By compared the results calculated from the equation with the results calculated from the code, it is found that the maximum pressure increased. The results showed density stratified is an import factor for silo pressure calculation and the equation obtained in this paper can provide references for the theory of silo pressure calculation.

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Huang, Yong Hui, Rong Hui Wang, and Xiao Feng Huang. "Calculation of the Interfacial Tensile Stress of CFST Members under Axial Pressure." Advanced Materials Research 250-253 (May 2011): 1638–45. http://dx.doi.org/10.4028/www.scientific.net/amr.250-253.1638.

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Based on plane strain theory, the formula for calculating the tensile stress on the interface between the steel tube and concrete under the axial pressure was derived, and the stress distribution coefficient K was analyzed. Practical formula for calculating the interfacial tensile stress of CFST members under low stress condition was fitted. Using the fitted formula the interfacial stress calculation process can be greatly simplified, and the results have enough assurance. This formula can be easily applied to CFST members’ interfacial stress calculation.

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Siluyanova, M. V., and A. О. Fertikov. "Calculation of lubricant flow in the slide bearing of the aviation engine reducer." VESTNIK of Samara University. Aerospace and Mechanical Engineering 18, no. 2 (July 2, 2019): 75–88. http://dx.doi.org/10.18287/2541-7533-2019-18-2-75-88.

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A method has been developed for calculating the pressure distribution in a cylindrical slide bearing. We present the process of designing a heavy-duty slide bearing as a component of the reduction gearbox of a bypass turbojet engine as the object of our investigation. The process comprises the following stages: specification of the supporting structure; calculation of pressure distribution in the slide bearing for different eccentricities and angles of rotation of the shaft journal; calculation of the effect of shaft journal precession on pressure distribution; calculation of pressure distribution taking into account the channels of oil supply to the bearing. The results obtained in the experimental activities are given. The analysis carried out shows that the calculation helps to predict the location and size of pressure and rarefaction areas, to position the holes for oil supply, which will significantly improve the conditions of lubricant flow in the bearing.

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Zhu, Ya Zhi, Shao Ping Meng, Wei Wei Sun, Wei Wang, Yu Long Feng, and Chen Hua Jin. "Distribution of Lateral Pressure in Large Diameter Squat Silos under Eccentric Discharge." Applied Mechanics and Materials 226-228 (November 2012): 1420–25. http://dx.doi.org/10.4028/www.scientific.net/amm.226-228.1420.

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The eccentric discharge of stored solids in squat silos has caused many failures, especially that in metal silos. However, these failures are poorly interpreted by specialists. In particular, the lateral pressure distribution on vertical wall couldn’t be accurately recognized. In order to set out the method to calculate static lateral pressure, the appearance of stored solids in silos after eccentric discharge is researched. In this study, based on the overall balance method (OBM), the method for calculating lateral static pressure in squat silos after eccentric discharge is proposed. Four cases are listed according to different discharge stages. Calculative formulae are deducted for each case. This method is also focusing on unsymmetrical distribution characteristic of the lateral pressure. Two calculative examples are listed and the results of which illustrate the necessity of lateral pressure calculation in squat silos.

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Poduška, Jan, Pavel Hutař, Andreas Frank, Gerald Pinter, and Luboš Náhlík. "Lifetime Calculation of Soil-Loaded Non-Pressure Polymer Pipes." Key Engineering Materials 827 (December 2019): 141–46. http://dx.doi.org/10.4028/www.scientific.net/kem.827.141.

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Outstanding durability of plastic pressure and non-pressure pipes can cause difficulties, when a reasonable lifetime estimation is needed. It is impossible to prove the lifetime by testing, but there is a method of calculation that can provide a certain idea about the expected lifetime. The lifetime estimation is based on the assumption that the failure occurs as a result of the slow crack growth mechanism and it is calculated using the linear elastic fracture mechanics approach. Numerical simulations of crack growth in the pipe are necessary for this calculation. These simulations must consider various effects that can play a role in the lifetime. This paper deals with the lifetime calculations of a pressure and a non-pressure corrugated pipe considering the soil loads acting on pipes when they are buried. In the simulation of the pressure pipe, a combination of loads is applied that consists of internal pressure, residual stress and the soil loads. The influence of the loads is discussed. The non-pressure corrugated pipe is loaded by the soil loads only.

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Volkov, V. P., and D. R. Salikhyanov. "ON RING DEFORMATION BY INTERNAL PRESSURE." Izvestiya. Ferrous Metallurgy 62, no. 3 (June 20, 2019): 195–200. http://dx.doi.org/10.17073/0368-0797-2019-3-195-200.

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Large-sized rings, manufactured by various methods of metal forming, are used in many industries. For the power industry, it is relevant to manufacture of retaining rings made of non-magnetic austenitic steel in order to strengthen the winding frontal parts of the rotors of turbine-type generators of a large unit capacity. In the process of generator operating, the retaining ring is one of the most loaded elements. As a result, material of retaining rings should have high strength properties, sufficient plasticity and good magnetic inductivity. Deformation of rings by internal pressure is the most promising and effective way of their cold hardening, providing a favorable and uniform stress-strain state of the metal in the manufacture of non-magnetic retaining rings for powerful turbine-type generators. Since the finished ring must acquire specific dimensions and a specified deformation degree in the process of cold hardening, the urgent task is calculation of the billet dimensions. The existing calculation procedure relies heavily on experimental manufacture data and is applicable only to a narrow range of rings, which reduces the accuracy of calculation and, ultimately, leads to an increase in ring allowances and a decrease in the metal utilization factor. In this research work a new technique for calculating the initial dimensions of rings, which is based on the incompressibility condition was developed and proposed. Taking into account the assumed boundary conditions, a system of two equations with three terms is compiled. To solve an incomplete equation system, it was suggested to introduce additional equations – in first version of the technique, the well-known solution of Nadai was used. In the second version – the condition of constancy of relative thickness of the ring wall permissible from the experimental data of deformation of rings of different sizes was used. The results of calculating the rings initial dimensions for both proposed techniques were compared with the experimental data. The maximum deviation from experimental data does not exceed 4 % and the deviation average value does not exceed 1 %, which indicates a sufficiently high accuracy of the proposed calculation techniques and the possibility of using them in manufacturing practice.

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Agrawal, Ajay K., S. Krishnan, and Tah-teh Yang. "Use of Subdomains for Inverse Problems in Branching Flow Passages." Journal of Fluids Engineering 115, no. 2 (June 1, 1993): 227–32. http://dx.doi.org/10.1115/1.2910128.

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For inverse problems in complex flow passages, a calculation procedure based on a multizone Navier-Stokes method was developed. A heuristic approach was employed to derive wall shape corrections from the wall pressure error. Only two subdomains sharing a row of control volumes were used. The grid work in the common region was identical for both subdomains. The flow solver, inverse calculation procedure, multizone Navier-Stokes method and subdomain inverse calculation procedure were validated independently against experimental data or numerical predictions. Then, the subdomain inverse calculation method was used to determine the wall shape of the main duct of a branching flow passage. A slightly adverse pressure gradient was prescribed downstream of the sidebranch. Inverse calculations resulted in a curved wall diffuser for which the wall pressure distribution matched the design (prescribed) wall pressure distribution. The present method was illustrated for laminar, incompressible flows in branching passages. However, the method presented is flexible and can be extended for turbulent flows in multiply connected domains.

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Liu, Qiao Feng, Jing Ru Han, Hai Ying Chen, and Chun Ming Zhang. "Verifying Calculation of Reactor Pressure Vessel Fast Neutron Fluence." Advanced Materials Research 986-987 (July 2014): 985–89. http://dx.doi.org/10.4028/www.scientific.net/amr.986-987.985.

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The reactor pressure vessel is an unchangeable component of the light water reactor. To some extent, the life of the pressure vessel depends on the fast neutron fluence. In addition, the fast neutron fluence is an important parameter for radiation protection. So, the fast neutron fluence is one of the main parameters which should be verifying calculated by the reviewers. The verifying calculation of the fast neutron fluence of one reactor pressure vessel is presented in this paper, and the standard deviation between the verifying and designing calculations is lower than 10%. The reasons for the deviation are discussed.

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Luan, Zhi Bo, Hou Hua Pang, and Xiao Dong Tan. "The Numerical Analysis of Leakage in Ultrahigh Pressure Seal Structure." Applied Mechanics and Materials 248 (December 2012): 433–37. http://dx.doi.org/10.4028/www.scientific.net/amm.248.433.

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This article states seal clearance and fluid leakage.By means of pressure distribution calculation and theoretical analysis, theoretically it establishs the mathematical model of the leakage with liquid material, the sealing structure and the fuel tank between the internal and external pressure.The whole processes on Matlab platform meet the complex engineering requirements,so the calculation process is simple and convenient. By calculating the results should be very intuitive, it closes to the sealing gap and leakage distribution curve. Thus, it is sure sealing clearance is the first element in the ultra-high pressure seal system.

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Al Khaburi, J., E. A. Nelson, J. Hutchinson, and A. A. Dehghani-Sanij. "Impact of multilayered compression bandages on sub-bandage interface pressure: a model." Phlebology: The Journal of Venous Disease 26, no. 2 (March 2011): 75–83. http://dx.doi.org/10.1258/phleb.2010.009081.

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Background Multi-component medical compression bandages are widely used to treat venous leg ulcers. The sub-bandage interface pressures induced by individual components of the multi-component compression bandage systems are not always simply additive. Current models to explain compression bandage performance do not take account of the increase in leg circumference when each bandage is applied, and this may account for the difference between predicted and actual pressures. Objective To calculate the interface pressure when a multi-component compression bandage system is applied to a leg. Method Use thick wall cylinder theory to estimate the sub-bandage pressure over the leg when a multi-component compression bandage is applied to a leg. Results A mathematical model was developed based on thick cylinder theory to include bandage thickness in the calculation of the interface pressure in multi-component compression systems. In multi-component compression systems, the interface pressure corresponds to the sum of the pressures applied by individual bandage layers. However, the change in the limb diameter caused by additional bandage layers should be considered in the calculation. Adding the interface pressure produced by single components without considering the bandage thickness will result in an overestimate of the overall interface pressure produced by the multi-component compression systems. At the ankle (circumference 25 cm) this error can be 19.2% or even more in the case of four components bandaging systems. Conclusion Bandage thickness should be considered when calculating the pressure applied using multi-component compression systems.

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Zhou, Yu, and Yi Wang. "Calculation Domain and Boundary Conditions for Push-Pull Ventilation." Advanced Materials Research 374-377 (October 2011): 419–24. http://dx.doi.org/10.4028/www.scientific.net/amr.374-377.419.

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CFD simulation is a useful tool for studying. However, in reality there are often complex, unsteady air flow patterns and large geometry domain and complex boundary conditions which are very difficult to totally take into consideration in the simulations. So sometimes we made the calculation domain not the same with geometry domain and simplified the boundary conditions. In this paper, five cases were made to study the calculation domain and boundary conditions for push-pull ventilation. According to the analyses and calculations the walls with windows and door closed setting for wall boundary conditions were not correct. On that basis cracks added, and the boundary conditions were pressure-inlet, and the pressure was zero. The calculation domain was reduced, the result was some different: the tendency was the same, but the difference of specific point values was some big. The new boundaries of the reduce calculation domain were set for pressure-inlet, and the pressure was zero. Under this condition, the cracks could be simplified to wall boundary conditions.

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Szlaga, Marek. "Balancing axial force in centrifugal pumps with pump out vanes." E3S Web of Conferences 137 (2019): 01028. http://dx.doi.org/10.1051/e3sconf/201913701028.

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Application of pump out vanes is one of the solutions to reduce hydraulic axial force generated during centrifugal pump operation. This article presents the cause of the occurrence of hydraulic axial force and method of calculating pressure distribution at the rear of the impeller used to design pump out vanes properly. It illustrates results of pump out vanes CFD calculations and its validation by measurements. The article reviews the methods of reducing pressure on the rear wall of the centrifugal pump's rotor using pump out vanes. It presents empirical formulae allowing calculation of pressure depending on the geometrical parameters of the blades. The article presents various design solutions of pump out vanes.

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Korovkin, Vladimir. "Numerical simulation of urban berthing quays in a dense housing." Environment. Technology. Resources. Proceedings of the International Scientific and Practical Conference 2 (June 17, 2015): 153. http://dx.doi.org/10.17770/etr2015vol2.236.

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Calculation of pile quay gantry type as a frame with rigid crossbarand a rigid beam, is a special case of the decision method, presented by N. Gersevanov. This method was widely used in the technical literature and regulatory documents. Translation of manual calculation on the computer almost retained the existing design scheme.Practical implementation of the engineering universal method offered early to calculation of mooring embankments in relation to a thin wall, is given by anchored inclined piles. In the calculation scheme bottom sealing is not used, and entered stiffness characteristics of the soil, clarifying the nature of the work structure.The obtained simplified solution determines the lateral pressure in the silo variable width. Engineering calculations showed that pressure is redistributed on the sheet pilling wall and the inclined piles from external soil pressure.Comparative calculations, taking into account the deformation characteristics of the soil showed a significant impact on efforts in the elements of the embankment compared to method N. Gersevanov.

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Joachimiak, D., M. Joachimiak, and P. Krzyślak. "The analysis of the calculation process related to labyrinth sealing with extraction." International Journal of Applied Mechanics and Engineering 18, no. 4 (December 1, 2013): 1057–66. http://dx.doi.org/10.2478/ijame-2013-0066.

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Abstract The work presents a calculation process enabling one-dimensional numerical calculations of labyrinth sealing. A DSV program determines the thermodynamic parameters of gas in the sealing chambers with extraction. The influence of the sealing length upon the stability of a matrix solution of the system of equations with the use of Cond(C) parameter is analysed. Next, the operation of the software extended with a module that enables determination of the initial pressure p0, to which the assumed mass flow for a set geometry and sealing length would correspond is discussed. The work analyzes Cond(C) and initial pressure values for various sealing lengths with an assumed leak value. The work also compares the values of static pressures on the extraction plane, as obtained from the measurements, to theoretically calculated values. The calculations and comparisons were made for various heights of incomplete sealing fissures

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Котиев, Georgiy Kotiev, Наказной, Oleg Nakaznoy, Беляков, Vladimir Belyakov, Клубничкин, Evgeniy Klubnichkin, Клубничкин, and Vladislav Klubnichkin. "The influence of the distribution of normal movers` pressures of tracked forest machine ЛЗ-4 and ЛЗ-5 on the rutting." Forestry Engineering Journal 6, no. 3 (October 10, 2016): 167–76. http://dx.doi.org/10.12737/21695.

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In the article the method of calculation of static loads on the elements of running system tracked forest machine. The methodology of calculation of static pressure rollers and tracks un-loaded and loaded logging machines on the ground (road surface). The method of calculation and construction of diagrams of specific pressures harvesting machine on the ground, taking into account attached to it active force and the position of the center of the static pressure.

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Shen, Kai, Hong Chen, Shi Fan Gu, and Ji Min Ni. "Research on Calculation Method of Engine Cooling Fan." Advanced Materials Research 732-733 (August 2013): 495–500. http://dx.doi.org/10.4028/www.scientific.net/amr.732-733.495.

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It’s introduced the method of calculation, modeling techniques and solution techniques of the aerodynamic performance of engine cooling fan. Based on a fan-tunnel test, the relation between static pressure, power, efficiency with volume flow is calculated in Fluent. It is proposed a few improved models and compared the calculations of different models. It’s analyzed the problems and reasons in the calculations of models and proposed the improved methods in fan test and numerical calculation. Keywords:Cooling Fan, Aerodynamic Performance, Models

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Chen Jun-Xiang, Yu Ji-Dong, Geng Hua-Yun, and He Hong-Liang. "Temperature and pressure calculation of porous materials." Acta Physica Sinica 66, no. 5 (2017): 056401. http://dx.doi.org/10.7498/aps.66.056401.

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Shishkin, S. F., A. S. Shishkin, and V. B. Ponomarev. "Calculation of pressure losses during pneumatic transport." NOVYE OGNEUPORY (NEW REFRACTORIES), no. 12 (January 23, 2020): 51–55. http://dx.doi.org/10.17073/1683-4518-2019-12-51-55.

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A method for calculating pressure losses during pneumatic transport is considered with the aim of choosing the most favorable operating mode, which allows to reduce the consumption of compressed air. It has been established that the generally accepted formulas for calculating pressure losses along the path, calculated as the sum of the pressure losses for pure gas and material, do not explain the fact of the initial decrease in pressure losses with increasing air flow rate, and then their growth. The importance of accounting for changes in air density and air flow velocity along the length of the pipe, as well as the need to take into account the overlap of part of the pipeline section with material in the case of high concentrations, is shown. It is proposed to determine the pressure loss using the Bernoulli equation in integral form, for example, the Gauss method using eight nodes. The applicability of the method for calculating both straight and inclined sections of pipelines is established. The experimental results of studying and analyzing the proposed isothermal model in a vacuum pneumatic transport laboratory installation are presented. An example of calculating the pressure loss for an industrial pneumatic conveying system with a pipe length of 450 m and an inner diameter of 147 mm at various flow rates of the material is shown. Ill. 4. Ref. 21. Tab. 1.

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SUGAWARA, Hirofumi, and Junsei KONDO. "Errors in Calculation of Satulation Vapor Pressure." Journal of Japan Society of Hydrology and Water Resources 7, no. 1 (1994): 440–43. http://dx.doi.org/10.3178/jjshwr.7.440.

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Sega, Marcello, Balázs Fábián, and Pál Jedlovszky. "Pressure Profile Calculation with Mesh Ewald Methods." Journal of Chemical Theory and Computation 12, no. 9 (August 24, 2016): 4509–15. http://dx.doi.org/10.1021/acs.jctc.6b00576.

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Milano, Giuseppe, and Toshihiro Kawakatsu. "Pressure calculation in hybrid particle-field simulations." Journal of Chemical Physics 133, no. 21 (December 7, 2010): 214102. http://dx.doi.org/10.1063/1.3506776.

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IMADO, Keiji, Masuji NAGATOSHI, Atsuyoshi MIURA, and Hioomi MIYAGAWA. "Calculation of contact pressure in conformal contact." Proceedings of the JSME annual meeting 2003.4 (2003): 149–50. http://dx.doi.org/10.1299/jsmemecjo.2003.4.0_149.

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Heinrich, J. C., and E. McBride. "Calculation of pressure in a mushy zone." International Journal for Numerical Methods in Engineering 47, no. 1-3 (January 10, 2000): 735–47. http://dx.doi.org/10.1002/(sici)1097-0207(20000110/30)47:1/3<735::aid-nme791>3.0.co;2-j.

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Griffiths, D. V., and C. O. Li. "Accurate pore pressure calculation in undrained analysis." Engineering Computations 6, no. 4 (April 1989): 339–42. http://dx.doi.org/10.1108/eb023788.

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Journal articles on the topic 'Pressure calculation'

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