The objective of this paper is to establish a simple two-dimensional theoretical model in an attempt to use a computer to numerically simulate the experimental results of Hummel regarding the rolling-up and interaction of the leading-edge and trailing edge vortex sheets on a delta wing. It was found experimentally that when the leading vortex is present the trailing-edge vortex sheet will roll up another vortex downstream from the trailing-edge. Furthermore, the circulation of the leading-edge vortex is opposite in direction to that of the trailing-edge vortex. The numerical results are in good agreement with the experimental pictures. (Translations, China, Chinese Language).

Acta Numerica has established itself as the prime forum for the presentation of definitive reviews of numerical analysis topics. The invited review papers, by leaders in their respective fields, allow researchers and graduate students alike quickly to grasp trends and developments. Highlights of the 1995 issue include articles on sequential quadratic programming, mesh adaption, free boundary problems and particle methods in continuum computations.

This acclaimed series provides survey articles on the present state and future direction of research in important branches of applied mechanics. Volume 31 provides the following fully referenced, and comprehensive articles:A New Integrable Shallow Water Equation discusses the initial value problem and soliton solutions for a newly discovered, completely integrable, dispersive shallow water equation as well as the elastic collision properties of the N-soliton solutionThe Onset and Development of Thermal Convection in Fully Developed Shear Flows focuses on a few basic states involving a Boussinesq fluid and fully developed forced flows, mainly of the Couette or Poiseuille typeVortex Element Methods for Flow Simulation covers vortex patches and filaments and a critical account of difficulties, limitations, and continuing efforts to improve the simulations of laminar or peturbulent flows through the use of vortex elementmethodsMicromechanics Constitutive Description of Thermoelastic Martensitic Transformations is concerned with the micromechanics description of transformation plasticity, incorporating microstructure, crystallography, thermodynamics and micromechanics into the continuum formulation of the macroscopic constitutive behavior.