Abstract
A set of solutions of the time-dependent diffusion equation for two-region bounded systems in spherical and cylindrical geometries is presented. Two types of solutions are given for each geometry: the general solution and a solution for the case where the spatial distribution of the thermal neutron flux is constant inside the inner region. These solutions provide the theoretical background for the development of a new method of measuring the thermal neutron macroscopic absorption cross section. The theoretical description of the method worked out for small samples is in good agreement with the experimental results presented. The principles of measuring the neutron transport cross section using small samples and mathematical solutions are described. The possibility of applying a sinusoidally modulated neutron source is presented. Special attention is paid to proper averaging of the thermal neutron diffusion parameters and to the problem of boundary effects. The so-called thermal neutron average dynamic parameters have been used. Results obtained from the modified diffusion theory compare satisfactorily with those obtained form the one-speed transport and P{sub 3} theory approximations. (au) (56 refs.).
Woznicka, U
[1]
- Henryk Niewodniczanski Inst. of Nuclear Physics, Krakow (Poland)
Citation Formats
Woznicka, U.
Time-dependent thermal neutron field in two-region bounded systems.
Sweden: N. p.,
1991.
Web.
Woznicka, U.
Time-dependent thermal neutron field in two-region bounded systems.
Sweden.
Woznicka, U.
1991.
"Time-dependent thermal neutron field in two-region bounded systems."
Sweden.
@misc{etde_10136043,
title = {Time-dependent thermal neutron field in two-region bounded systems}
author = {Woznicka, U}
abstractNote = {A set of solutions of the time-dependent diffusion equation for two-region bounded systems in spherical and cylindrical geometries is presented. Two types of solutions are given for each geometry: the general solution and a solution for the case where the spatial distribution of the thermal neutron flux is constant inside the inner region. These solutions provide the theoretical background for the development of a new method of measuring the thermal neutron macroscopic absorption cross section. The theoretical description of the method worked out for small samples is in good agreement with the experimental results presented. The principles of measuring the neutron transport cross section using small samples and mathematical solutions are described. The possibility of applying a sinusoidally modulated neutron source is presented. Special attention is paid to proper averaging of the thermal neutron diffusion parameters and to the problem of boundary effects. The so-called thermal neutron average dynamic parameters have been used. Results obtained from the modified diffusion theory compare satisfactorily with those obtained form the one-speed transport and P{sub 3} theory approximations. (au) (56 refs.).}
place = {Sweden}
year = {1991}
month = {Oct}
}
title = {Time-dependent thermal neutron field in two-region bounded systems}
author = {Woznicka, U}
abstractNote = {A set of solutions of the time-dependent diffusion equation for two-region bounded systems in spherical and cylindrical geometries is presented. Two types of solutions are given for each geometry: the general solution and a solution for the case where the spatial distribution of the thermal neutron flux is constant inside the inner region. These solutions provide the theoretical background for the development of a new method of measuring the thermal neutron macroscopic absorption cross section. The theoretical description of the method worked out for small samples is in good agreement with the experimental results presented. The principles of measuring the neutron transport cross section using small samples and mathematical solutions are described. The possibility of applying a sinusoidally modulated neutron source is presented. Special attention is paid to proper averaging of the thermal neutron diffusion parameters and to the problem of boundary effects. The so-called thermal neutron average dynamic parameters have been used. Results obtained from the modified diffusion theory compare satisfactorily with those obtained form the one-speed transport and P{sub 3} theory approximations. (au) (56 refs.).}
place = {Sweden}
year = {1991}
month = {Oct}
}