Study of Compressible High Speed Gas Flow in Piping System : 2nd Report, Piping Systems with Sudden Enlargement

This paper reports the results of experiments and finite element simulations on the structural response of piping systems to internal detonation loading. Specifically, the work described in this paper focuses on the forces that are produced at tee-junctions that lead to axial and bending structural responses of the piping system. Detonation experiments were conducted in a 2-in. (50 mm) diameter schedule 40 piping system that was fabricated using 304 stainless steel and welded to ASME B31.3 standards. The 4.1 m (162-in.) long piping system included one tee and was supported using custom brackets and cantilever beams fastened to steel plates that were bolted to the laboratory walls. Nearly-ideal detonations were used in a 30/70 H2-N2O mixture at 1 atm initial pressure and 300 K. Pressure and hoop, axial, and support strains were measured using a high-speed (1 MHz) digital data acquisition system and calibrated signal conditioners. It was concluded that detonations propagate through the run of a 90° tee with relatively little disturbance in either direction. The detonation load increases by approximately a factor of 2 when the detonation enters through the branch. The deflections of the cantilever beam supports and the hoop and axial pipe strains could be adequately predicted by finite element simulations. The support loads are adequately predicted as long as the supports are constrained to the piping. This paper shows that with relatively simple models, quantitative predictions of tee forces can be made for the purposes of design or safety analysis of piping systems subject to internal detonations.

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The Scaling of Pressure Fluctuations From Equal-Tee Piping Components for In-Plant Noise Prediction

Flow-Induced Vibration ◽

10.1115/pvp2003-2088 ◽

2003 ◽

Author(s):

Denis G. Karczub ◽

Fred W. Catron ◽

Allen C. Fagerlund

Keyword(s):

Pressure Fluctuation ◽

High Speed ◽

Gas Flow ◽

Characteristic Curve ◽

Internal Noise ◽

High Mass ◽

Piping System ◽

Gas Density ◽

System Components ◽

Fluctuation Scaling

An important element of in-plant noise modeling for high-speed gas flow, in addition to the noise generated by control valves, is the noise due to piping system components such as tees which becomes significant at high mass flow rates. An effective tool for the modeling of noise due to piping system components is non-dimensional pressure fluctuation scaling. The current paper outlines procedures for characterization of the internal noise due to an equal tee with unequal outlet flows using non-dimensional pressure fluctuation scaling. Experimental data is presented demonstrating general collapse of the measured data onto a single characteristic curve for several combinations of flow velocity and gas density under steady-state flow conditions. Flow ratios of 1:2, 1:3, 1:4 and 2:3 between each of the two outlet legs from the equal tee are considered, as well as the affect of gas density over a range of 345kPaG to 1380kPaG.

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Characterisation of Air-Water Two-Phase Flow Using a Wire-Mesh Sensor

Volume 6: Fluids and Thermal Systems; Advances for Process Industries, Parts A and B ◽

10.1115/imece2011-62777 ◽

2011 ◽

Cited By ~ 1

Author(s):

Carlos E. F. do Amaral ◽

O´liver B. S. Scorsim ◽

Eduardo N. Santos ◽

Marco Jose´ da Silva ◽

Marco Germano Conte ◽

...

Keyword(s):

High Speed ◽

Gas Flow ◽

Two Phase Flow ◽

Flow Patterns ◽

Industrial Applications ◽

Wire Mesh ◽

Phase Flow ◽

Two Phase ◽

Flow Rates ◽

Piping Systems

Two phase flow occurs in many industrial applications, mainly in the transport of mixtures. Many patterns can be produced according to the liquid and gas flow rates. The identification of these patterns is very important in the design of piping systems and equipments. This work proposes an experimental study to identify multiphase flow patterns of water and air in horizontal pipes. The study was developed using an experimental circuit of 26 mm diameter and 9.2 m length pipe, at Thermal Sciences Lab (LACIT) at the Federal University of Technology - Parana´. To characterize the flow patterns, an intrusive mesh electrodes sensor was used, which allows the detailed visualization of the phases distribution. Tests were made using several experimental settings of water and gas flow rates. Measurements were compared to images obtained by high speed camera and the temporal void fraction series which were analyzed with the use of PDF and PSD functions, showing the singularities for each two-phase flow pattern.

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Flow Modellium software package for calculating high-speed compressible gas flow

Журнал вычислительной математики и математической физики ◽

10.31857/s004446690003544-9 ◽

2018 ◽

Vol 58 (11) ◽

pp. 1932-1954

Author(s):

M. Petrov ◽

Keyword(s):

Software Package ◽

High Speed ◽

Gas Flow ◽

Compressible Gas Flow ◽

Compressible Gas

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Heat Transmission in High Speed Gas Flow (3rd Report)

Transactions of the Japan Society of Mechanical Engineers ◽

10.1299/kikai1938.18.67_31 ◽

1952 ◽

Vol 18 (67) ◽

pp. 31-35

Author(s):

Kensuke KAWASHIMO ◽

Shigebumi AOKI

Keyword(s):

High Speed ◽

Gas Flow ◽

Heat Transmission

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Non-Linear Design Verification of Nuclear Power Piping According to ASME III NB/NC

Volume 1: Plant Operations, Maintenance, Installations and Life Cycle; Component Reliability and Materials Issues; Advanced Applications of Nuclear Technology; Codes, Standards, Licensing and Regulatory Issues ◽

10.1115/icone16-48910 ◽

2008 ◽

Author(s):

Lingfu Zeng ◽

Lennart G. Jansson

Keyword(s):

Nuclear Power ◽

Design Evaluation ◽

Piping System ◽

Design Verification ◽

Intensive Study ◽

Non Linear ◽

Piping Systems ◽

Design Requirements

A nuclear piping system which is found to be disqualified, i.e. overstressed, in design evaluation in accordance with ASME III, can still be qualified if further non-linear design requirements can be satisfied in refined non-linear analyses in which material plasticity and other non-linear conditions are taken into account. This paper attempts first to categorize the design verification according to ASME III into the linear design and non-linear design verifications. Thereafter, the corresponding design requirements, in particular, those non-linear design requirements, are reviewed and examined in detail. The emphasis is placed on our view on several formulations and design requirements in ASME III when applied to nuclear power piping systems that are currently under intensive study in Sweden.

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Comparison of Failure Modes of Piping Systems With Wall Thinning Subjected to In-Plane, Out-of-Plane, and Mixed Mode Bending Under Seismic Load: An Experimental Approach

Journal of Pressure Vessel Technology ◽

10.1115/1.4001517 ◽

2010 ◽

Vol 132 (3) ◽

Cited By ~ 12

Author(s):

Izumi Nakamura ◽

Akihito Otani ◽

Masaki Shiratori

Keyword(s):

Dynamic Behavior ◽

Failure Modes ◽

Seismic Load ◽

Piping System ◽

Shake Table ◽

Shake Table Tests ◽

Wall Thinning ◽

Piping Systems ◽

Out Of Plane ◽

Plane Bending

Pressurized piping systems used for an extended period may develop degradations such as wall thinning or cracks due to aging. It is important to estimate the effects of degradation on the dynamic behavior and to ascertain the failure modes and remaining strength of the piping systems with degradation through experiments and analyses to ensure the seismic safety of degraded piping systems under destructive seismic events. In order to investigate the influence of degradation on the dynamic behavior and failure modes of piping systems with local wall thinning, shake table tests using 3D piping system models were conducted. About 50% full circumferential wall thinning at elbows was considered in the test. Three types of models were used in the shake table tests. The difference of the models was the applied bending direction to the thinned-wall elbow. The bending direction considered in the tests was either of the in-plane bending, out-of-plane bending, or mixed bending of the in-plane and out-of-plane. These models were excited under the same input acceleration until failure occurred. Through these tests, the vibration characteristic and failure modes of the piping models with wall thinning under seismic load were obtained. The test results showed that the out-of-plane bending is not significant for a sound elbow, but should be considered for a thinned-wall elbow, because the life of the piping models with wall thinning subjected to out-of-plane bending may reduce significantly.

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The Influence of Support Hardware and Piping System Seismic Response on Snubber Support Damping

Journal of Pressure Vessel Technology ◽

10.1115/1.2842329 ◽

1997 ◽

Vol 119 (4) ◽

pp. 451-456 ◽

Cited By ~ 2

Author(s):

C. Lay ◽

O. A. Abu-Yasein ◽

M. A. Pickett ◽

J. Madia ◽

S. K. Sinha

Keyword(s):

Seismic Response ◽

Fundamental Frequency ◽

Damping Ratio ◽

Damping Coefficient ◽

Piping System ◽

Nodal Displacement ◽

Damping Coefficients ◽

Fundamental Frequencies ◽

Piping Systems

The damping coefficients and ratios of piping system snubber supports were found to vary logarithmically with pipe support nodal displacement. For piping systems with fundamental frequencies in the range of 0.6 to 6.6 Hz, the support damping ratio for snubber supports was found to increase with increasing fundamental frequency. For 3-kip snubbers, damping coefficient and damping ratio decreased logarithmically with nodal displacement, indicating that the 3-kip snubbers studied behaved essentially as coulomb dampers; while for the 10-kip snubbers studied, damping coefficient and damping ratio increased logarithmically with nodal displacement.

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