Engineering Commons^™

A Prompt D-D Neutron Calibration Of A Plastic Scintillator Detector, Dal H. Jensen

Nuclear Engineering ETDs

ABSTRACT

A new approach to the measurement of the neutron yield of low intensity (~ 2 x 10 neutrons/pulse) 0-0 neutron generators in a single pulse is described. A cylindrical (20.32 cm radius by 20.32 cm height) scin­tillator of Pilot-Bis optically coupled to a Phillips 57AVP photomulti­plier with a 20 cm diameter photocathode. The light pulse resulting from the neutron burst is fed into a voltage integrator calibrated in neutrons/ count.

The initial calibration of the stable neutron generator used in the scintillator calibration was performed using a silver activation detector (PT-502) designed by LASL. The data obtained for the …

Safeguards Considerations For A Htgr Nuclear Fuel Cycle, Philip G. Johnson

Nuclear Engineering ETDs

Given that the prime objective of safeguards for special nuclear materials (SNM) is nonproliferation of nuclear weapons, it is logical that safeguards priorities should be commensurate with the relative suitabilities of the various SNM forms in existence for application in nuclear explosives. The SNM forms in each reactor fuel cycle, for example, should be screened and ordered according to their relative suitabilities for such misapplication. Significant considerations in assigning protection priorities include the relative suitabilities based on materials characteristics, inherent protection features of the mateerials or the processing of the SNM forms, the quantities of these materials in existence, and …

Methods For Calculating Energy Deposition Using Coupled Neutron-Gamma Ray Transport, Lewis Douglas Rigdon

Nuclear Engineering ETDs

In radiation damage problems, it is desirable to know not only the neutron and gamma ray fluxes but also the energy deposition due to those fluxes. Following the recent availability of coupled neutron-gamma ray, multigroup-multitable cross sections and associated fluence-to-KERMA factors, an automated method has been developed for obtaining the energy deposition in a material region due to local neutron and gamma ray fluxes. Cross section sets which combine neutron and photon transport as well as a production matrix for neutron-induced gamma rays are used in the transport calculation. Thus in one discrete ordinates transport calculation, the energy deposition from …

Correlation Of Theory And Experiment For The Dynamics Of A Pressurized Water Reactor, J. G. Thakkar

Masters Theses

Dynamic tests were performed on the Carolina Power and Light Company's H. B. Robinson Unit 2 to determine the frequency response of the PWR steam supply system. Step inputs and multi-frequency binary signals of various sequence lengths and bit durations were used. The signals were introduced manually by the operator both for reactivity perturbation and steam flow perturbation tests. The experimental results were analyzed on and IBM 360/65 computer. The test results were compared with theoretical results predicted by a mathematical model of the system.

A mathematical model for the H. B. Robinson system was formulated. In most cases, the …

Experimental Study Of Electron Density And Confinement Time In An Electrostatically-Plugged Cusp Device Using A Microwave Interferometer, Robert Louis Hayward

Masters Theses

"The average electron density and electron confinement time in an electrostatically plugged magnetic spindle cusp device are studied using a 20 GHz microwave interferometer. The results are compared with the predictions from approximate theoretical equations. With a magnetic induction in the point cusp of 5000 Gauss, a plasma is produced by injecting a 5 mA, 500 eV electron beam into hydrogen gas at 10^-5 Torr. The measured electron density is 2 x 10^-10 cm^-3 and the measured confinement time is 80 ysec, which agree to within a factor of two with values predicted by theory"--Abstract, page ii.

Effect Of Photoneutrons On Transients Of Beryllium Reflected Reactors, Safdar Ahmad Ali

Doctoral Dissertations

"An analytical model is developed to account for the photoneutron sources present in a beryllium reflector. The time-dependent, two- dimensional and three energy-group diffusion equations are written with an additional photoneutron source term. Then an approximate flux composed of two spatial shapes chosen beforehand, each having an unknown time coefficient, is inserted into time-dependent multigroup equations and the weighted residual criterion is applied. This yielded multimode kinetics equations with generalized definitions for conventional matrix parameters: generation time, reactivity, delayed neutron and delayed photoneutron fraction matrices.

Two transients are analyzed for the University of Missouri Research Reactor: simulation of rod drop …