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in creator/contributor: "Chang, Y.W."

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Comparison of ICEPEL predictions with single elbow flexible piping system experiment

The ICEPEL Code for coupled hydrodynamic-structural response analysis of piping systems is used to analyze an experiment on the response of flexible piping systems to internal pressure pulses. The piping system consisted of two flexible Nickel-200 pipes connected in series through a 90/sup 0/ thick-walled stainless steel elbow. A tailored pressure pulse generated by a calibrated pulse gun is stabilized in a long thick-walled stainless steel pipe leading to the flexible piping system which ended… more

Date: January 1, 1978

Creator: A-Moneim, M.T. & Chang, Y.W.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Computer simulation of LMFBR piping systems. [Accident conditions]

Integrity of piping systems is one of the main concerns of the safety issues of Liquid Metal Fast Breeder Reactors (LMFBR). Hypothetical core disruptive accidents (HCDA) and water-sodium interaction are two examples of sources of high pressure pulses that endanger the integrity of the heat transport piping systems of LMFBRs. Although plastic wall deformation attenuates pressure peaks so that only pressures slightly higher than the pipe yield pressure propagate along the system, the interaction … more

Date: January 1, 1977

Creator: A-Moneim, M.T.; Chang, Y.W. & Fistedis, S.H.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Comparison of a Two-Dimensional Hydrodynamics Code (Rexco) to Excursion Experiments for Fast Reactor Containment.

No Description Available.

Date: January 1, 1972

Creator: Ash, J. E.; Chang, Y. W. & Julke, R. T.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Bauschinger effects and work-hardening in spheroidized steels

The effects of cementite particles and subgrain boundaries on work-hardening behavior of spheroidized carbon steels were investigated by making direct measurements of residual internal stresses. These internal stresses developed due to plastic incompatibilities between elastic particles and an elastic-plastic matrix. A continuum analysis of these internal stress fields, based upon a multiple slip model, is presented and is found to be in good accord with the experiments. The internal stresses a… more

Date: May 1, 1977

Creator: Chang, Y W

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Application of containment codes to LMFBRs in the United States

The application of containment codes to predict the response of the fast reactor containment and the primary piping loops to HCDAs is described. Five sample problems are given to illustrate their applications. The first problem deals with the response of the primary containment to an HCDA. The second problem deals with the coolant flow in the reactor lower plenum. The third proem concerns sodium spillage and slug impact. The fourth problem deals with the response of a piping loop. The fifth pro… more

Date: January 1, 1977

Creator: Chang, Y. W.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Comparison of REXCO Code Predictions with SRI SM-2 Experimental Results

This report deals with the REXCO-code predictions of the SRI SM-2 test. Two calculations were performed with the REXCO-HEP code: one used the pressure history of the core detonation products as input and the other the pressure-volume relations of the detonation products as input. The other inputs of the computer analysis are the vessel and the core-barrel dimensions and boundary conditions, the constitutive equations of the vessel and the core barrel materials, and the equation of state for the… more

Date: August 1978

Creator: Chang, Y. W. & Gvildys, J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Structural dynamics in LMFBR containment analysis: a brief survey of computational methods and codes

In recent years, the use of computer codes to study the response of primary containment of large, liquid-metal fast breeder reactors (LMFBR) under postulated accident conditions has been adopted by most fast reactor projects. Since the first introduction of REXCO-H containment code in 1969, a number of containment codes have evolved and been reported in the literature. The paper briefly summarizes the various numerical methods commonly used in containment analysis in computer programs. They are… more

Date: January 1, 1977

Creator: Chang, Y. W. & Gvildys, J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Dynamic characteristics of Bridgestone low shear modulus-high damping seismic isolation bearings

Bridgestone Company of Japan is one of the leading seismic bearing manufacturers in the world. Their bearings have very good performance records. It appears that Bridgestone`s high damping bearings are made of a blend of filled natural and synthetic rubbers with fillers and plastizers whereas in the United States, the high damping compound is a carbon filled natural rubber. To compare the properties of the two different kinds of high damping compounds, Argonne National Laboratory (ANL) purchase… more

Date: June 1, 1993

Creator: Chang, Y. W. & Seidensticker, R. W.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Eulerian method for large-displacement fluid-structure interaction in reactor containments

An Eulerian method for analyzing large-displacement fluid-structure interaction in reactor containments is presented. The emphasis is on the development of a generalized hydrodynamic scheme to treat the irregular cells created by the movement of the structure with respect to the fixed Eulerian coordinates. A relaxation equation is derived from the boundary condition at the fluid-structure interface for the solution of the pressure at the interface. By combining this with the Poisson equation a … more

Date: January 1, 1977

Creator: Chang, Y. W. & Wang, C. Y.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Evaluation of Lagrangian, Eulerian, and arbitrary Lagrangian-Eulerian methods for fluid-structure interaction problems in HCDA analysis

The analysis of fluid-structure interaction involves the calculation of both fluid transient and structure dynamics. In the structural analysis, Lagrangian meshes have been used exclusively, whereas for the fluid transient, Lagrangian, Eulerian, and arbitrary Lagrangian-Eulerian (quasi-Eulerian) meshes have been used. This paper performs an evaluation on these three types of meshes. The emphasis is placed on the applicability of the method in analyzing fluid-structure interaction problems in HC… more

Date: January 1, 1979

Creator: Chang, Y. W.; Chu, H. Y.; Gvildys, J. & Wang, C. Y.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Analysis of LMFBR primary system response to an HCDA using an Eulerian computer code

Applications of an Eulerian code to predict the response of LMFBR containment and primary piping systems to hypothetical core disruptive accidents (HCDA), and to analyze sodium spillage problems, are described. The computer code is an expanded version of the ICECO code. Sample problems are presented for slug impact and sodium spillage, dynamics of the HCDA bubbles, and response of a piping loop. (JWR)

Date: January 1, 1975

Creator: Chang, Y. W.; Wang, C. Y.; Chu, H. Y.; Abdel-Moneim, M. T. & Gvildys, J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Site characteristics of Argonne National Laboratory in Illinois

This report reviews the geology and topography of the Argonne National Laboratory, near Lemont, Illinois. It describes the thickness and stratigraphy of soils, glacial till, and bedrock in and adjacent to the laboratory and support facilities. Seismic surveys were also conducted through the area to help determine the values of seismic wave velocities in the glacial till which is important in determining the seismic hazard of the area. Borehole log descriptions are summarized along with informat… more

Date: January 1, 1995

Creator: Chang, Y.W.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Some remaining problems in HCDA analysis. [LMFBR]

The safety assessment and licensing of liquid-metal fast breeder reactors (LMFBRs) requires an analysis on the capability of the reactor primary system to sustain the consequences of a hypothetical core-disruptive accident (HCDA). Although computational methods and computer programs developed for HCDA analyses can predict reasonably well the response of the primary containment system, and follow up the phenomena of HCDA from the start of excursion to the time of dynamic equilibrium in the syste… more

Date: January 1, 1981

Creator: Chang, Y.W.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Analysis of the FFTF primary-system response to an HCDA

No Description Available.

Date: January 1, 1974

Creator: Chang, Y.W. & Gvildys, J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Comparisons of REXCO code predictions with SRI SM-2 experimental results

SRI International has performed a series of simple model (SM) experiments for the Clinch River Breeder Reactor Project (CRBR). The SM tests consisted of five experiments. The energy source used to simulate the core-disassembly accident loads was a PETN-microsphere mixture, which was well calibrated. These experiments were well instrumented and performed under carefully controlled conditions. The experimental data can be used as reliable test data for validation of computer codes, as well as the… more

Date: January 1, 1979

Creator: Chang, Y.W. & Gvildys, J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Response of a base-isolated large liquid metal reactor plant to seismic loads

In recent years, base isolation has been applied to various civil structures such as bridges and buildings for the purpose of reducing its acceleration to below the level of ground accelerations during seismic events. The basic principal of base isolation is to introduce a soft layer of material between structure foundation to allow a degree of flexibility in horizontal motions which could reduce the seismic accelerations during earthquakes. If base isolation is properly designed, it shifts the… more

Date: January 1, 1989

Creator: Chang, Y.W. & Gvildys, J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Analysis of LMFBR containment response to an HCDA using a multifield Eulerian code. [MICE code]

During a hypothetical core disruptive accident (HCDA), a core meltdown may cause the fuel cladding to rupture and the fuel fragments to penetrate into the sodium coolant. The heat in the molten fuel may cause the liquid sodium to boil, changing its phase. The interactions between materials are so complicated that a single-material model with homogenized material properties is not adequate. In order to analyze the above phenomena more realistically, a Multifield Implicit Continuous-Fluid Euleria… more

Date: January 1, 1977

Creator: Chu, H.Y. & Chang, Y.W.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Monitoring of soft high damping elastomeric bearings for earthquake isolation

Over the last 20 years several practical systems for the protection of buildings and their contents against the effects of earthquakes were developed. These systems rely on effectively decoupling the building from the strong horizontal ground accelerations that are some of the most damaging features of an earthquake. The isolation of small buildings against earthquakes poses particular problems for high damping elastomer. systems. It was recognized that one way to overcome these problems was to… more

Date: July 1, 1993

Creator: Coveney, V. A.; Kuroda, T.; Kobatake, M.; Nita, Y.; Kulak, R. F.; Chang, Y. W. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Seismic response of LMFBR tanks with imperfections

This paper deals with seismic responses of imperfect circular tanks. Physical imperfection due to manufacturing tolerances and numerical imperfection due to finite element spatial discretization are described. Numerical imperfections produced by 4-node and 9-node Lagrangian shell elements are examined. A convergence study is performed in which the number of the shell elements required to capture the dominant ''out-of-roundness'' modes under seismic excitations is determined. The response of a s… more

Date: January 1, 1985

Creator: Gvildys, J.; Ma, D.C. & Chang, Y.W.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

An overview of the EBR-II PRA (Probabilistic Risk Assessment)

Experimental Breeder Reactor-II, EBR-II, is a 60 MW(t) liquid sodium cooled, pool type fast reactor which has operated successfully as a power reactor and irradiation facility for over 25 years. Argonne National Laboratory is currently performing a Probabilistic Risk Assessment of EBR-II. An overview of the PRA is presented with special attention to those issues which are important to EBR-II such as the passive decay heat removal capabilities and the passive shut down capability provided by the… more

Date: January 1, 1990

Creator: Hill, D.J.; Chang, Y.W.; Deitrich, L.W.; Ragland, W.A. (Argonne National Lab., IL (USA)); Lehto, W.K. & Schaeffer, R.W. (Argonne National Lab., Idaho Falls, ID (USA))

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Comparison of seismic response of ordinary and base-isolated structures

Seismic isolation is growing rapidly worldwide as a cost-effective and reliable design strategy for a wide range of critical and important facilities (e.g., hospitals, computer centers, etc.) Shimizu Corporation of Japan has a test facility at Tohoku University in Sendai, Japan. The test facility was constructed in 1986 and has two buildings: one is base isolated and the other is conventionally founded. The buildings are full-size, three-story reinforced concrete structures. The dimensions and … more

Date: January 1, 1992

Creator: Kuroda, T.; Kobatake, M. (Shimizu Corp., Tokyo (Japan)); Seidensticker, R.W. & Chang, Y.W. (Argonne National Lab., IL (United States))

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Comparison of seismic response of ordinary and base-isolated structures

Date: April 1, 1992

Creator: Kuroda, T.; Kobatake, M.; Seidensticker, R. W. & Chang, Y. W.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

An overview of seismic-induced hydrodynamic phenomena in LMR reactor tanks

Liquid metal reactors (LMTs) usually contain a huge volume of liquid sodium as reactor coolant. Since most reactor components are submerged in the sodium coolant, the seismic-induced hydrodynamic effects are of great importance in the design of LMR reactor components. Because LMRs operate at low pressures, the reactor components are made of thin-walled structures. Of interest in reactor design, in particular, are the hydrodynamic pressures imposed on various components, such as the reactor vess… more

Date: January 1, 1991

Creator: Ma, D.C.; Chang, Y.W. & Seidensticker, R.W.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Dominant seismic sloshing mode in a pool-type reactor tank

Large-diameter LMR (Liquid Metal Reactor) tanks contain a large volume of sodium coolant and many in-tank components. A reactor tank of 70 ft. in diameter contains 5,000,000 of sodium coolant. Under seismic events, the sloshing wave may easily reach several feet. If sufficient free board is not provided to accommodate the wave height, several safety problems may occur such as damage to tank cover due to sloshing impact and thermal shocks due to hot sodium, etc. Therefore, the sloshing response … more

Date: January 1, 1987

Creator: Ma, D.C.; Gvildys, J. & Chang, Y.W.

Item Type: Article

Partner: UNT Libraries Government Documents Department