Thermal neutron transport near a moderator discontinuity using the method of weighted residuals - I. Theory

Beynon, T.D.; Moon, J R

doi:10.1088/0022-3727/5/5/311

Cited by 5 publications

(4 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A homogeneous non-multiplying moderator is contained within 1 x 1 < a with a free The multigroup equations for the scalar flux @(x) for an energy group g(g E N ) is with Our comparisons with transport theory have been made using the P1 Selengut-Goertzel approximation to the scattering kernel in the integral Boltzmann equation, In this approximation the appropriate forms of the transport equation for the one-group and multigroup scalar fluxes, $(x) and #g(x) respectively become (Beynon and Moon 1972)…”

Section: Basic Considerationsmentioning

confidence: 99%

A numerical study of optimum boundary conditions for multigroup diffusion theory

Beynon¹,

Hopper²

1978

J. Phys. D: Appl. Phys.

Self Cite

View full text Add to dashboard Cite

Using an energy dependent extrapolated endpoint Z0g as a variable parameter, a least-squares technique is used to minimise differences between the solutions of the multi-group transport and diffusion equations for one-dimensional slab geometry. The optimised Z0g values thus obtained are compared with the familiar prescriptions based on one-group theory, particularly the Milne condition cg Sigma trgZ0g=0.71. Applications to some moderating materials show that while the Milne formula is adequate for natural iron, a better prescription for light water would be cg Sigma trgZ0g=0.35. A similar analysis for extrapolation lengths lambda g yields an optimised fit of Sigma trg lambda g=0.62 for light water moderators.

show abstract

Section: Basic Considerationsmentioning

confidence: 99%

A numerical study of optimum boundary conditions for multigroup diffusion theory

Beynon¹,

Hopper²

1978

J. Phys. D: Appl. Phys.

Self Cite

View full text Add to dashboard Cite

show abstract

“…Detailed descriptions of the analysis employed in the present computations have been given elsewhere (Beynon andMoon 1972, 1973), and we shall only outline here the basic forms of the equations used. Two adjacent semi-infinite slabs have been considered with a constant temperature in each half.…”

Section: Theorymentioning

confidence: 99%

Some theoretical considerations of neutron rethermalization near temperature and poisoning discontinuities in light water

Beynon

Moon

1974

J. Phys. D: Appl. Phys.

Self Cite

View full text Add to dashboard Cite

A numerical investigation is made of neutron rethermalization effects in light water near physical temperature discontinuities and discontinuities in 1/ν-poisoning. It is shown that calculations of effective neutron temperatures in unpoisoned water systems possessing only temperature discontinuities are insensitive to the details of the scattering model assumed, and that rethermalization occurs within 1 cm of the temperature interface. However, with or without the presence of physical temperature discontinuities but with one region poisoned, effective temperature differences of up to 70 K exist between predictions using the Nelkin model and the Haywood frequency distribution for the water molecule. In this case, rethermalization occurs up to 2 cm into the poisoned region.

show abstract

“…This method has been discussed and justified in some detail earlier (Beynon and Moon 1972, hereafter referred to as I). Briefly, it consists of expanding the scalar flux of neutrons, 4(r, E ) , at position Y and energy E, as…”

Section: Introductionmentioning

confidence: 99%

Spectral, luminescence, and lasing properties of a yttrium scandium gallium garnet crystal activated with chromium and erbium

Zharikov¹,

Il'ichev²,

Kalitin³

et al. 1986

Sov. J. Quantum Electron.

View full text Add to dashboard Cite

Using the method of weighted residuals, a detailed numerical study is made of the neutronics of spherical cold neutron sources composed of liquid hydrogen and liquid deuterium in reactor moderators of light water, heavy water and graphite, Particular attention is paid to the physical effects at the cold source boundary. The computations allow a number of conclusions to be made on the best designs of spherical cold source configurations. It is found that for small spherical sources there is little difference in neutron gain using either normal-hydrogen or para-hydrogen, and that the largest gains are obtainable from large deuterium-filled sources.

show abstract

Thermal neutron transport near a moderator discontinuity using the method of weighted residuals - I. Theory

Cited by 5 publications

References 10 publications

A numerical study of optimum boundary conditions for multigroup diffusion theory

A numerical study of optimum boundary conditions for multigroup diffusion theory

Some theoretical considerations of neutron rethermalization near temperature and poisoning discontinuities in light water

Spectral, luminescence, and lasing properties of a yttrium scandium gallium garnet crystal activated with chromium and erbium

Contact Info

Product

Resources

About