Showing papers in "Journal of Computational Physics in 1977"

TL;DR: In this paper, a numerical algorithm integrating the 3N Cartesian equations of motion of a system of N points subject to holonomic constraints is formulated, and the relations of constraint remain perfectly fulfilled at each step of the trajectory despite the approximate character of numerical integration.

TL;DR: In this paper, the authors describe the use of arbitrary sampling distributions chosen to facilitate the estimate of the free energy difference between a model system and some reference system, but the conventional Monte Carlo methods of obtaining such averages are inadequate for the free-energy case.

TL;DR: In this article, the authors extended previous work on the solution of the Navier-Stokes equations in the presence of moving immersed boundaries which interact with the fluid and introduced an improved numerical representation of the δ-function.

TL;DR: In this paper, an approach to numerical convection is presented that exclusively yields upstream-centered schemes, which start from a meshwise approximation of the initial-value distribution by simple basic functions, e.g., Legendre polynomials.

TL;DR: In this paper, a finite-difference approach is proposed for compressible flow conservation laws, involving more of the physics in the conservation laws and more attractive schemes are proposed for more efficient computations.

TL;DR: In this article, a binary collision model by the Monte Carlo method is proposed for plasma simulations with particle codes, which describes a collision integral of the Landau form, and the results are in good agreement with theoretical ones.

TL;DR: In this article, a three-dimensional finite-difference model of air flow over an irregular lower surface is described, and the model is nonhydrostatic and the anelastic approximation has been used to filter sound waves.

TL;DR: In this paper, the authors presented a new method which sidesteps the ill conditioning, guarantees convergence to the unique best least-squares fit, gives positive coefficients, and produces fits orders of magnitude more accurate than any which have so far been published.

TL;DR: In this article, a method for automatic generation of boundary-fitted curvilinear coordinate systems, where the transformed coordinates are solutions of an elliptic differential system in the physical plane and where the coordinate lines are coincident with all boundaries of a general multiply-connected, two-dimensional region containing any number of arbitrarily shaped bodies, is described along with a suitable computer code for implementing the method.

TL;DR: In this paper, the utility of mappings to solve numerically problems in infinite regions was investigated and it was shown that mappings are useful if the solution being sought behaves in a simple way at infinity; otherwise, they are not particularly helpful.

TL;DR: Two methods are presented to eliminate the second-order derivatives in parabolic equations, while keeping the fourth-order accuracy and the tridiagonal nature of the schemes.

TL;DR: In this article, the potential energy, the forces and the virial in a computer ensemble of N polarizable point dipoles were analyzed using an iterative scheme for use in molecular dynamics calculations.

TL;DR: In this paper, higher-order collocation procedures resulting in tridiagonal matrix systems are derived from polynomial spline interpolation and by Hermitian (Taylor series) finite-difference discretization.

TL;DR: In this paper, the authors considered the conformation of a molecule by the unusual means of proposing the matrix D of all interatomic distances subject to a priori energetic and geometric constraints, and then calculating the corresponding atomic coordinates.

TL;DR: In this article, the random choice method is analyzed and appropriate boundary conditions are described, and applications to time-dependent reacting gas flow in one dimension are carried out for solving problems where the diffusion constant vanishes or is very small, and where artificial or numerically induced diffusion cannot be tolerated.

TL;DR: In this article, a finite element method for the numerical solution of the two-dimensional Stefan problem is described, where at each time step, the free boundary is approximated by a polygonal line whose vertices coincide with triangulation nodes.

TL;DR: In this article, a simulation of 2D turbulence in a square region with periodic boundary conditions has been performed using a highly accurate approximation of the inviscid Navier-Stokes equations to which a modified viscosity has been added.

TL;DR: The time evolution and stability of the Kortewegde Vries-Burgers equation are studied numerically in this paper, where it is found that nonanalytic initial data satisfying the boundary conditions of the problem evolve asymptotically into the steady-state shocks predicted by a time independent analysis.

TL;DR: In this article, the boundary potential is computed by finding a set of correction charges on the boundary only, and convolving them with a suitable Green's function, which is equivalent to convolving the source distribution with the Green's functions, but requires less storage and computer time.

TL;DR: In this paper, a procedure for numerical solution of the Navier-Stokes equations for flow about arbitrarily shaped two-dimensional bodies is given, based on a technique of automatic numerical generation of a curvilinear coordinate system having a coordinate line coincident with the body contour regardless of its shape.

TL;DR: In this paper, the authors studied the soliton behavior of the regularized long-wave (RLW) equation and showed that the behavior of solutions of the RLW equation mirrors closely, both qualitatively and quantitavely, the behaviour of the Korteweg-de Vries equation.

TL;DR: In this article, different procedures for treating artificial boundaries are analyzed, and it is shown that many commonly used methods give bad results, and a new procedure is developed for the case where the asymptotic behaviour of the coefficient matrices is known.

TL;DR: In this paper, a nonlinear method of filtering computational noise from fourth and higher order convective difference schemes is introduced which removes the computational noise without inflicting significant amplitude losses in sharply peaked waves.

TL;DR: In this article, a multilevel, free-surface, viscous primitive equation ocean model was developed to study the response of baroclinic oceans to stationary and moving weather systems.

TL;DR: The method allows for the inclusion of additional information, such as uncertainties in the data and other constraints given by the general phenomenology of the experiment or theory, and can be applied to the calculation of numerical derivatives and integrals of data points.

TL;DR: The operation counts for this problem are derived so that they are applicable even if the number of mesh points in any direction is small, and some input-output considerations for coding problems which require auxiliary storage are discussed.

TL;DR: In this article, a particle simulation code was developed for low-frequency plasma phenomena, which is particularly suited for the investigation of low frequency plasma phenomena in which the transverse displacement current is neglected and the self-consistent magnetic fields are retained.

TL;DR: In this article, the numerical calculation of rotational flow at large Reynolds number is considered, where the vortices move under their mutually induced velocities plus a random component to simulate effects of viscosity.

TL;DR: In this article, an iterative finite difference model is developed to describe two-dimensional periodic gravity waves on the surface of a fluid containing vorticity in the form of a vertical shear current.