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in subjects: "Transients"

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Severe accident core heatup transients in modular high temperature gas-cooled reactors without operating Reactor Cavity Cooling Systems

The ultimate decay heat removal system for the current Modular High Temperature Gas-Cooled reactors is a completely passive natural convection air cooling loop. This paper considers an extremely remote accident scenario, where even this passive system fails, and heat rejection is only via a layer of thermal insulation to the reactor silo structure and the surrounding soil. The results show that even in this case the peak fuel temperatures remain well within safe limits. However, vessel and conc… more

Date: January 1, 1988

Creator: Kroeger, P. G.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

SCORE-EVET: a computer code for the multidimensional transient thermal-hydraulic analysis of nuclear fuel rod arrays. [BWR; PWR]

The SCORE-EVET code was developed to study multidimensional transient fluid flow in nuclear reactor fuel rod arrays. The conservation equations used were derived by volume averaging the transient compressible three-dimensional local continuum equations in Cartesian coordinates. No assumptions associated with subchannel flow have been incorporated into the derivation of the conservation equations. In addition to the three-dimensional fluid flow equations, the SCORE-EVET code ocntains: (a) a one-… more

Date: February 1, 1978

Creator: Benedetti, R. L.; Lords, L. V. & Kiser, D. M.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Source-jerk analysis using a semi-explicit inverse kinetic technique

A method is proposed for measuring the effective reproduction factor, k, in subcritical systems. The method uses the transient response of a subcritical system to the sudden removal of an extraneous neutron source (i.e., a source jerk). The response is analyzed using an inverse kinetic technique that least-squares fits the exact analytical solution corresponding to a source-jerk transient as derived from the point-reactor model. It has been found that the technique can provide an accurate means… more

Date: January 1, 1985

Creator: Spriggs, G.D. & Pederson, R.A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

A theoretical prediction of critical heat flux in subcooled pool boiling during power transients

Understanding and predicting critical heat flux (CHF) behavior during steady-state and transient conditions are of fundamenatal interest in the design, operation, safety of boiling and two-phase flow devices. This paper discusses the results of a comprehensive theoretical study made specifically to model transient CHF behavior in subcooled pool boiling. This study is based upon a simplified steady-state CHF model in terms of the vapor mass growth period. The results obtained from this theory in… more

Date: January 1, 1988

Creator: Pasamehmetoglu, K. O.; Nelson, R. A. & Gunnerson, F. S.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

TRANSIENT RADIATION EFFECTS IN CAPACITORS AND DIELECTRIC MATERIALS

Measurements of dielectric leakage, capacitance, electric strength, andd charge scattering phenomena were performed at the Kukla and Godiva III critical assemblies for tantalum and aluminum electrolytic, wax- and oilimpregnated paper, mylar, mica, and ceramic capacitors, and for mylar and Vitamin B-impregnated paper. Leakage data indicate that gamma induced conductivity in capacitor dielectric varies directly with gamma DELTA , where gamma is the gamma radiation rate and DELTA is 0.9 for mylar,… more

Date: August 15, 1961

Creator: Wicklein, H. W. & Dickhaut, R. H.

Item Type: Book

Partner: UNT Libraries Government Documents Department

open access

PNL technical review of pressurized thermal-shock issues. [PWR]

Pacific Northwest Laboratory (PNL) was asked to develop and recommend a regulatory position that the Nuclear Regulatory Commission (NRC) should adopt regarding the ability of reactor pressure vessels to withstand the effects of pressurized thermal shock (PTS). Licensees of eight pressurized water reactors provided NRC with estimates of remaining effective full power years before corrective actions would be required to prevent an unsafe operating condition. PNL reviewed these responses and the r… more

Date: July 1, 1982

Creator: Pedersen, L. T.; Apley, W. J.; Bian, S. H.; Defferding, L. J.; Morgenstern, M. H.; Pelto, P. J. et al.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Blanket technology experiments at Argonne National Laboratory

Argonne National Laboratory has the largest US program for the development of blanket technology. The goals of the program are to resolve critical issues for different blanket concepts, to develop the understanding and predictive capability of blanket behavior, and to develop the technology needed to build and operate advanced fusion blankets. The projects within the program are liquid metal MHD, breeder neutronics, tritium oxidation, transient electromagnetics, FLIBE chemistry, and insulator c… more

Date: February 1, 1988

Creator: Mattas, R. F.; Reed, C. B.; Picologlou, B.; Finn, P.; Clemmer, R.; Porges, K. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Natural convection phenomena in a nuclear power plant during a postulated TMLB' accident

After the TMI (Three Mile Island) accident, there has been significant interest in analyzing and understanding the phenomena that may occur in a PWR (Pressurized Water Reactor) accident which may lead to partial or total core meltdown and degradation. Natural convection is one of the important phenomena. In the present paper the results of two numerical simulations of (1) four-loop PWR and (2) three-loop PWR are presented. The simulations were performed with the COMMIX(2) computer code. Our ana… more

Date: January 1, 1987

Creator: Domanus, H. M.; Schmitt, R. C.; Sha, W. T.; Shah, V. L. & Han, J. T.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Cryogenic recovery analysis of forced flow supercritical helium cooled superconductors

A coupled heat conduction and fluid flow method of solution was presented for cryogenic stability analysis of cabled composite superconductors of large scale magnetic coils. The coils are cooled by forced flow supercritical helium in parallel flow channels. The coolant flow reduction in one of the channels during the spontaneous recovery transient, after the conductor undergoes a transition from superconducting to resistive, necessitates a parallel channel analysis. A way to simulate the parall… more

Date: August 1, 1977

Creator: Lee, A. Y.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Further considerations of critical heat flux in saturated pool boiling during power transients

In this paper, we further evaluate our previously postulated transient CHF model. First, we verify the steady-state CHF model on which the transient model is based by using recent macrolayer-thickness data. We also include the effect of thermal storage in the heater that we previously neglected. The use of a simplified approach in the prediction of the instantaneous surface heat flux for given pwoer generation rates considerably improves the predictive capability of the transient critical heat-… more

Date: January 1, 1988

Creator: Pasamehmetoglu, K.O. & Nelson, R.A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Research for Electric Energy Systems

This report documents the technical progress in investigations. The first investigation is concerned with the measurement of magnetic fields in support of epidemiogical and in vitro studies of biological field effects. NIST cohosted a workshop on exposure and biological parameters that should be considered during the vitro studies with extremely low frequency (ELF) magnetic and electric fields. Also, equations were developed to predict the magnetic field in a parallel plate magnetic field expos… more

Date: June 1, 1991

Creator: Anderson, W.E. (ed.)

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Stress-related phenomena in transient radiation-induced absorption in optical fibers

The optical properties of materials can be modified by exposure to radiation and research to investigate these radiation-induced phenomena has intensified over the last several decades. The advent of optical fiber technology and the many applications of optical fiber for information transmission have sharply increased the interest in these investigations. Optical fibers present a long optical transmission path and that path may traverse different adverse environments, including radiation areas.… more

Date: January 1, 1988

Creator: Looney, L. D.; Lyons, P. B. & Kelly, R. E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Detection and diagnosis of abnormal transients in nuclear power plants

This document describes a simulation-based algorithm that combines fuzzy logic with macroscopic conservation equations to diagnose multiple-failure events subject to uncertainties in transient data. Clusters of single-failure data points of similar characteristics are obtained through a pattern recognition algorithm and the cluster centers are combined in the space of macroscopic inventory derivatives to generate multiple-failure cluster centers. A fuzzy membership function is used to represent… more

Date: January 1, 1991

Creator: Lee, J. C.; Rank, P. J.; Hawkes, E.; Wehe, D. K. (Michigan Univ., Ann Arbor, MI (United States). Dept. of Nuclear Engineering) & Reifman, J. (Argonne National Lab., IL (United States))

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Overview of the Division 2351 Neutron Generator Test Facility waveform digitizing system. [Explosively activated neutron generators]

All neutron generator waveforms from units tested at the SLA neutron generator test site are digitized and the digitized data stored in the CDC 6600 tape library for display and analysis using the CDC 6600 computer. The digitizing equipment consists mainly of seven Biomation Model 8100 transient recorders, Digital Equipment Corporation PDP 11/20 computer, RK05 disk, seven-track magnetic tape transport, and appropriate DEC and SLA controllers and interfaces. The PDP 11/20 computer is programmed … more

Date: February 1, 1978

Creator: Bryant, T.C. Jr.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Final report of fuel dynamics Test E7

Test data from an in-pile failure experiment of high-power LMFBR-type fuel pins in a simulated $3/s transient-overpower (TOP) accident are reported and analyzed. Major conclusions are that (1) a series of cladding ruptures during the 100-ms period preceding fuel release injected small bursts of fission gas into the flow stream; (2) gas release influenced subsequent cladding melting and fuel release (there were no measurable FCI's (fuel-coolant interactions), and all fuel motion observed by the … more

Date: April 1, 1977

Creator: Doerner, R. C.; Murphy, W. F.; Stanford, G. S. & Froehle, P. H.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Outlet plenum mixing for transient overpower conditions of a one-exit nozzle LMFBR

Two types of transient tests were employed to model a one-exit nozzle LMFBR outlet plenum. Water was used as a test fluid in the simulation of constant flowrates, Transient Overpower (TOP) conditions. In the first test, simulated fuel flow was 85% and blanket flow was 15%, whereas in the second test, the fuel flow was 100%. This allowed the assessment of the mitigating effects of blanket flow upon the exit nozzle temperature transient. The flow field was clearly three-dimensional, and a less ac… more

Date: April 1, 1978

Creator: Howard, P. A.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

A theoretical prediction of critical heat flux in forced convection boiling during power transients

In this paper, a theoretical prediction of critical heat flux (CHF) during power transients in forced convective boiling is presented. The analysis is restricted to the departure from nucleate boiling (DNB) type of CHF at low qualities. The developed theory is compared with the experimental data available in the literature. The agreement is favorable. The results are discussed in terms of the various parameters affecting the transient CHF. This new model also is compared with the semi-empirical… more

Date: January 1, 1988

Creator: Pasamehmetoglu, K.O.; Nelson, R.A. & Gunnerson, F.S.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

LMFBR system-wide transient analysis: the state of the art and US validation needs

This paper summarizes the computational capabilities in the area of liquid metal fast breeder reactor (LMFBR) system-wide transient analysis in the United States, identifies various numerical and physical approximations, the degree of empiricism, range of applicability, model verification and experimental needs for a wide class of protected transients, in particular, natural circulation shutdown heat removal for both loop- and pool-type plants.

Date: January 1, 1982

Creator: Khatib-Rahbar, M.; Guppy, J.G. & Cerbone, R.J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Superconducting fault current limiter. Sixth quarterly technical progress report, November 8, 1979-February 7, 1980

Progress in developing an improved superconducting fault current limiter (SCFCL) is described. A mathematical model of the most promising SCFCL design was used for determining transient characteristics, thermal recovery characteristics, and for evaluating types of shunt resistors. Some experimental work was done on Nb/sub 3/Sn film properties. (LCL)

Date: January 1, 1980

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Operational, control and protective system transient analyses of the closed-cycle GT-HTGR power plant

This paper presents a description of the analyses of the control/protective system preliminary designs for the gas turbine high-temperature gas-cooled reactor (GT-HTGR) power plant. The control system is designed to regulate reactor power, control electric load and turbine speed, control the temperature of the helium delivered to the turbines, and control thermal transients experienced by the system components. In addition, it provides the required control programming for startup, shutdown, loa… more

Date: July 1, 1980

Creator: Openshaw, F.L. & Chan, T.W.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Advanced thermohydraulic simulation code for pool-type LMFBRs (SSC-P code)

Models for components and processes that are needed for simulation of thermohydraulic transient in a pool-type liquid metal fast breeder reactor (LMFBR) plant are described in this report. A computer code, SSC-P, has been developed as a part of the Super System Code (SSC) development project. A user's manual is being prepared as a separate document. 27 refs., 26 figs., 1 tab.

Date: September 1, 1980

Creator: Madni, I. K. & Cazzoli, E. G.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

HEATING 7. 1 user's manual

HEATING is a FORTRAN program designed to solve steady-state and/or transient heat conduction problems in one-, two-, or three- dimensional Cartesian, cylindrical, or spherical coordinates. A model may include multiple materials, and the thermal conductivity, density, and specific heat of each material may be both time- and temperature-dependent. The thermal conductivity may be anisotropic. Materials may undergo change of phase. Thermal properties of materials may be input or may be extracted fr… more

Date: July 1, 1991

Creator: Childs, K.W.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

LOFT Steam Generator thermal analysis Class I review

A Class 1 review of the thermal analysis of the LOFT Steam Generator and of the transient thermal analysis of LOFT steam generator thermal well was made to confirm compliance of the analyses with the LOFT Technical Specifications, with the LOFT integral test system - preliminary component design description for the steam generator, and with Appendix C of ANC Specification 60139. Included in this review is an examination of the thermal transients and conditions to insure adequate conservatism in… more

Date: October 6, 1977

Creator: Kinnaman, T.L.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Liquid metal plasma valve development

A program for the development of liquid-metal plasma valves (LMPVs) is discussed in detail. The program consisted of two tasks. The first was the development and testing of valves in the laboratory and the fabrication, instrumentation, testing and in-service operation of two valves at the Bonneville Power Administration (BPA) facilities of the Pacific Intertie HVDC Power Tansmission System at Celilo, Oregon. The second task was the design, development, fabrication, installation, and operation o… more

Date: June 1, 1978

Item Type: Report

Partner: UNT Libraries Government Documents Department