819,774 research outputs found
Four-Body Bound State Calculations in Three-Dimensional Approach
The four-body bound state with two-body interactions is formulated in
Three-Dimensional approach, a recently developed momentum space representation
which greatly simplifies the numerical calculations of few-body systems without
performing the partial wave decomposition. The obtained three-dimensional
Faddeev-Yakubovsky integral equations are solved with two-body potentials.
Results for four-body binding energies are in good agreement with achievements
of the other methods.Comment: 29 pages, 2 eps figures, 8 tables, REVTeX
Orthogonal, solenoidal, three-dimensional vector fields for no-slip boundary conditions
Viscous fluid dynamical calculations require no-slip boundary conditions.
Numerical calculations of turbulence, as well as theoretical turbulence closure
techniques, often depend upon a spectral decomposition of the flow fields.
However, such calculations have been limited to two-dimensional situations.
Here we present a method that yields orthogonal decompositions of
incompressible, three-dimensional flow fields and apply it to periodic
cylindrical and spherical no-slip boundaries.Comment: 16 pages, 2 three-part figure
Recent experiences with three-dimensional transonic potential flow calculations
Some recent experiences with computer programs capable of solving finitie-difference approximations to the full potential equation for the transonic flow past three dimensional swept wings and simple wing-fuselage combinations are discussed. The programs used are a nonconservative program for swept wings, a quasi-conservative finite-volume program capable of treating swept wings mounted on fuselages of slowly varying circular cross section, and a fully conservative finite volume scheme capable of treating swept wings and wing-cylinder combinations. The present capabilities of these codes are reviewed. The relative merits of the conservative and nonconservative formulations are discussed, and the results of calculations including corrections for the boundary-layer displacement effect are presented
Three-dimensional compressible stability-transition calculations using the spatial theory
The e(exp n)-method is employed with the spatial amplification theory to compute the onset of transition on a swept wing tested in transonic cryogenic flow conditions. Two separate eigenvalue formulations are used. One uses the saddle-point method and the other assumes that the amplification vector is normal to the leading edge. Comparisons of calculated results with experimental data show that both formulations give similar results and indicate that the wall temperature has a rather strong effect on the value of the n factor
Validation of a three-dimensional viscous analysis of axisymmetric supersonic inlet flow fields
A three-dimensional viscous marching analysis for supersonic inlets was developed. To verify this analysis several benchmark axisymmetric test configurations were studied and are compared to experimental data. Detailed two-dimensional results for shock-boundary layer interactions are presented for flows with and without boundary layer bleed. Three dimensional calculations of a cone at angle of attack and a full inlet at attack are also discussed and evaluated. Results of the calculations demonstrate the code's ability to predict complex flow fields and establish guidelines for future calculations using similar codes
Nuclear radiation environment analysis for thermoelectric outer planet spacecraft
Neutron and gamma ray transport calculations were performed using Monte Carlo methods and a three-dimensional geometric model of the spacecraft. The results are compared with similar calculations performed for an earlier design
Bound State Calculations of the Three-Dimensional Yakubovsky Equations with the inclusion of Three-Body Forces
The four-body Yakubovsky equations in a Three-Dimensional approach with the
inclusion of the three-body forces is proposed. The four-body bound state with
two- and three-body interactions is formulated in Three-Dimensional approach
for identical particles as function of vector Jacobi momenta, specifically the
magnitudes of the momenta and the angles between them. The modified three
dimensional Yakubovsky integral equations is successfully solved with the
scalar two-meson exchange three-body force where the Malfliet-Tjon-type
two-body force is implemented. The three-body force effects on the energy
eigenvalue and the four-body wave function, as well as accuracy of our
numerical calculations are presented.The four-body Yakubovsky equations in a
Three-Dimensional approach with the inclusion of the three-body forces is
proposed. The four-body bound state with two- and three-body interactions is
formulated in Three-Dimensional approach for identical particles as function of
vector Jacobi momenta, specifically the magnitudes of the momenta and the
angles between them. The modified three dimensional Yakubovsky integral
equations is successfully solved with the scalar two-meson exchange three-body
force where the Malfliet-Tjon-type two-body force is implemented. The
three-body force effects on the energy eigenvalue and the four-body wave
function, as well as accuracy of our numerical calculations are presented.Comment: 23 pages, 2 eps figures, 5 tables. Major changes; version to appear
in European Physical Journal
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