摘要:

AbstractFor given maximum surface and internal fuel temperatures and coolant inlet temperature, the optimum degree of artificial roughening of the surface of gas-cooled fast reactor fuel elements is such that the Stanton number is approximately doubled with respect to smooth rods. For given coolant temperatures and maximum clad temperature, the power per unit length of rod increases approximately linearly with increasing Stanton number. Core performance is not sensitive to possible uncertainties in friction factor (±25%), slight decrease in surface heat transfer, or to the fraction of the active rod which is roughened. By proper design, fuel cycle costs remain low (0.5 to 0.6 mil/kWh) for a substantial range of values of maximum clad temperature (600 to 700°C), maximum linear rating (12 to 18 kW/ft), and degree of surface roughening (1.5 to 2.5) with helium cooling of oxide rods.

ISSN:0029-5639    

DOI:10.13182/NSE68-A19234

出版商:Taylor&Francis    

年代:1968

数据来源: Taylor

摘要:

AbstractThe adjoint transport problem for gamma radiation is formulated and prescriptions for its Monte Carlo solution are given. Emphasis is put upon requirements for calculation of effects in shielding against fallout and the differential effect of source position. Results are given for two situations: a detector three feet above a uniform infinite source of 1.25-MeV photons, and another detector placed in an open pit with a similar source.

ISSN:0029-5639    

DOI:10.13182/NSE68-A19235

出版商:Taylor&Francis    

年代:1968

数据来源: Taylor

摘要:

AbstractResults from Monte Carlo calculations of the longitudinal and lateral development of the nucleon-meson cascade in iron initiated by 1- and 3-GeV protons are presented and compared with experimental results. In general, the calculated and experimental results are in good agreement, although in the 3-GeV case the calculation yields a smaller buildup of particles for the smaller penetration depths. The Monte Carlo results for the longitudinal development are also compared with available results from a calculation using the straightahead approximation, and the agreement is quite good.

ISSN:0029-5639    

DOI:10.13182/NSE68-A19236

出版商:Taylor&Francis    

年代:1968

数据来源: Taylor

摘要:

AbstractThe eigensolutions of the multigroup neutron transport equation for the isotropic scattering medium in plane geometry are found by developing Case's method. The solution of the adjoint equation is also given in an explicit form. The completeness of the eigensolutions is proved by using the orthogonality relation to the adjoint solution. The degeneracy for the continuous eigenvalue is expressed in two ways: the unit vector system and the eigenvector system. In the latter case the orthogonality is formed, and the eigenvector system is thought of as a proper normal mode. As an application of this method, the infinite medium Green's function is constructed.

ISSN:0029-5639    

DOI:10.13182/NSE68-A19237

出版商:Taylor&Francis    

年代:1968

数据来源: Taylor

摘要:

AbstractA discussion is presented of the quantum-mechanical derivation of the Boltzmann equation, along with a demonstration that use of the superlattice representation of McIrvine and Overhauser enables avoidance of singular and non-physical terms in the Hamiltonian of the neutron-moderator system. The formal validity of the Boltzmann equation in finite systems is analyzed, and it is shown that the transport description is physically meaningful for systems of dimensions>>10−4cm.

ISSN:0029-5639    

DOI:10.13182/NSE68-A19238

出版商:Taylor&Francis    

年代:1968

数据来源: Taylor

摘要:

AbstractThe two-group one-dimensional neutron transport equation with isotropic scattering is studied. No analytical solution is found, but the equations are cast in a form that is convenient for numerical computation. This computation involves the solution of two coupled singular integral equations. The explicit form of these equations is obtained for two half-space problems—the Milne problem and the constant isotropic source problem.

ISSN:0029-5639    

DOI:10.13182/NSE68-A19239

出版商:Taylor&Francis    

年代:1968

数据来源: Taylor

摘要:

AbstractParticular numerical methods are described for solving the two-group neutron transport equations obtained in a companion paper. Numerical solutions are presented for the Milne problem and the constant source problem, and the results are compared withP1,P3, and doubleP1calculations. The most interesting result is the occurrence of a resonance in the continuum expansion coefficient which appears to be due to a zero of the dispersion functionΩ(z) in the unphysical Riemann sheet.

ISSN:0029-5639    

DOI:10.13182/NSE68-A19240

出版商:Taylor&Francis    

年代:1968

数据来源: Taylor

摘要:

AbstractThe Stabilized March Technique, SMT, is extended to the numerical solution of second-order, inhomogeneous problems, i.e., the multigroup neutron diffusion equations in one space dimension, and the one-velocity neutron transport equation in one space dimension. In the SMT, the solution vector is expanded in a complete set of vectors which is used in an unstable difference equation. The error growth is controlled, however, by periodic matrix transformations and may be preset. The method has its greatest advantage in relation to the computational speed of conventional methods in elongated meshes, such as multigroup diffusion calculations, or low-order discrete ordinate orPNcalculations with many spatial mesh points.

ISSN:0029-5639    

DOI:10.13182/NSE68-A19241

出版商:Taylor&Francis    

年代:1968

数据来源: Taylor

摘要:

AbstractThe Schwarz-Christoffel conformal mapping of the interior of a regular hexagon upon the interior of a circle has been integrated analytically, as a simple irrational function of the Weierstrass equianharmonic elliptic function. The hexagonal coordinate system thus generated has broad applicability to the nuclear, thermodynamic, and stress analyses of hexagonal lattice reactors.

ISSN:0029-5639    

DOI:10.13182/NSE68-A19242

出版商:Taylor&Francis    

年代:1968

数据来源: Taylor

ISSN:0029-5639    

DOI:10.13182/NSE68-A19243

出版商:Taylor&Francis    

年代:1968

数据来源: Taylor