Engineering topics
Halstead, D. W.
Publications and source records attributed to Halstead, D. W..
Solutions to Kuessner's integral equation in unsteady flow using local basis functions
The computational procedure and numerical results are presented for a new method to solve Kuessner's integral equation in the case of subsonic compressible flow about harmonically oscillating planar surfaces with controls. Kuessner's equation is a linear transformation from pressure to normalwash. The unknown pressure is expanded in terms of prescribed basis functions and the unknown basis function coefficients are determined in the usual manner by satisfying the given normalwash distribution either collocationally or in the complex least squares sense. The present method of solution differs from previous ones in that the basis functions are defined in a continuous fashion over a relatively small portion of the aerodynamic surface and are zero elsewhere. This method, termed the local basis function method, combines the smoothness and accuracy of distribution methods with the simplicity and versatility of panel methods. Predictions by the local basis function method for unsteady flow are shown to be in excellent agreement with other methods. Also, potential improvements to the present method and extensions to more general classes of solutions are discussed.
BUCLAP2: A computer program for instability analysis of laminated long plates subjected to combined inplane loads. User's manual
The usage of the computer program BUCLAP2 is described. The program is intended for linear instability analysis of long, rectangular flat and curved laminated plates with arbitrary orientation of orthotropic axes in each layer. The loadings considered are combinations of inplane normal and shear loads. Arbitray elastic boundary conditions are included for the sides of the plate Instructions for use of the program are included along with Input data requirements, output information, and sample problems. For program description, see .
BUCLAP2: A computer program for instability analysis of laminated long plates subjected to combined inplane loads
This program description document describes the program structure and the design details of a CDC 6600 FORTRAN 4 digital computer program, BUCLAP2, which uses minimum energy principles to do an elastic stability analysis of curved and flat laminated rectangular long plates subjected to combined inplane normal and shear loads. Given the geometry, the material properties, and slected boundary conditions for the plate element, the program calculates the minimum buckling load for various wave lengths. The two parallel ends of the program calculates the minimum buckling load for various wave lengths. The two parallel ends of the long plate must be simply supported and arbitrary elastic boundary conditions may be imposed along either one or both external longitudinal sides. For guide to program use, see
Predicting and analyzing the thermal flux incident on test articles in a simulated space environment
The increase in importance and sophistication of thermal-vacuum testing has accentuated the problem of defining the environment to which the test article was subjected. An adequate definition of the test environment is essential to the verification of test-article thermal models. The technique used for defining the test environment at the NASA Manned Spacecraft Center Space Environment Simulation Laboratory and its application during a recent major thermal-vacuum testing program is discussed.
Analysis of the Apollo heat shield performance. Volume 2 - CHAD computer program
CHAD computer program for Apollo heat shield ablation performance analysis
Analysis of the Apollo heat shield performance. Volume 1 - Analytical methods
Analysis of Apollo heat shield using mathematical models