Use this URL to cite or link to this record in EThOS: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.474715
Title: A Study of Neutron Heating in Fusion Reactor Materials.
Author: Taylor, N. P.
Awarding Body: University of Birmingham
Current Institution: University of Birmingham
Date of Award: 1977
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Abstract:
An important. quarrti,ty iD the design and analysis of corrtr-IoLed thermonuclear reactor._s. is the rate of heating in the material of the breeder bIenke t , due ·to'nuclear interactions induced. by neutrons originating in the fusion plasma. This 'nuclear heating' consists of three parts: neutron heating, gamma heating and a,ctiva,tionheating. In this work a method is developed for the calculation of neutron heating rates, utilizing computer codes uhich are already in common use for fusion reactor neutronics calcu,.lations,and using nuclear data which is also readily available; mainly that data uhich is .e.Lr-eadyin use for the computet Lon of neutron fluxes. The introduction, chapter 1, reviews the principles of controlled thermonuclear r-ee.tccr-s, and conceptual designs for the .maLn types of reactors that have been proposed, 'Hith particula.r emphasis on the effects of the various designs on the neutronics of the breeder blanket region. The importance of neutron heating calculations is also discussed. In chapter 2, calculational methods used for estimates of neutron fluxes are reviewed, in particular the method of discrete ordin~.tes, as used in this 110rk. Data requirements of these cc:lculations arc discussed, and previously used methods for neutron heating calculations revie.. red. The theory 01' the present method for neutron heating calculations are presented in chapter 3. Equations are developed for the energy depositj,on in each principle neutron reaction type, and these are combined to give a general formula for total neutron energy deposition It is shown tha t any reaction type (except fission) can 'be represented by this equation. Ohap'ter 4 di acuase s the total energy r-el ee.sed in inelastic scattering events, and a'method for calculeting this is developed, for use in the equations of chapter 3. This method makes use of known energy levels in the nuclei of interest, end an evapora t i on model approximation for the continuum of higher energy levels. The results of chapter 3 are put :i,nto a form suitable for calculation in chapter 5. Averaging into energy multigroups is . discussed, and an eque.ti on for the multigroup energy deposi tion factors is developed. The use of these factors is described, vnd.. finally en alternative method for neutron heat Lng celcu~:;'tions, by overel l energy balance considerations, is outlined. The method developed in chapte r s 3 - 5 is applied in chc.pte r 6 to calculations of neut ron heat.Lng re.te s in a var-Lety of materials of interest in fusion rea.ctor design. These cs.Lcul.ations are perf'ormed 'both in simple slab configurations and in a simple fusion reactor blc:.nket design. Calculations of neutron heating by a previous method are also made for comperison purposes, and agreement is good in most regions. As a further check, the alternative method outlined at tile end of chapter 5 is e.Lso applied, and agr-eemerrt is again good. Chapter 7 turns to. an exe.minadiianof activetion heating rates in the seme fusion reactor b'Lanket design C.s used in chapte r 6. Activat.ion heating rc.t es , which ar-o found to be small compar-ed'With ! neutron heating rates, are presented both as a f'unct i.on of position and of time. Conclusions are made in chapter 8, ..There a f'Low die>gre.mof the ·va.:rious computing mc\hods and pr-ogr-amsinvolved is used to display the features of the different methods, end the advantages of the present method. A description of the use of the program ENBAL, ..rhd ch uses the methods for neutron heating developed in chapters 3 - 5, is provided in the appendix.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.474715  DOI: Not available
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