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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Computer program using numerical methods that calculates minimum time for space vehicle to meet its mission with optimum trajectory, and can maximize option if burning time is fixed
Trajectory optimization by explicit numerical methods
Evaluating methods of numerically integrating equations of motion for nonlinear dynamic analyses of shells of revolution by matrix displacement method
Computer methods for numerical solution of systems of nonlinear differential equations
Numerical methods of integration of the equations of motion of a controlled satellite under the influence of gravity-gradient torque are considered. The results of computer experimentation using a number of Runge-Kutta, multi-step, and extrapolation methods for the numerical integration of this differential system are presented, and particularly efficient methods are noted. A large bibliography of numerical methods for initial value problems for ordinary differential equations is presented, and a compilation of Runge-Kutta and multistep formulas is given. Less common numerical integration techniques from the literature are noted for further consideration.
A numerical method for the solution of large systems of nonlinear differential equations of the boundary-layer type is described. The method is a modification of the technique for satisfying asymptotic boundary conditions. The present method employs inverse interpolation instead of the Newton method to adjust the initial conditions of the related initial-value problem. This eliminates the so-called perturbation equations. The elimination of the perturbation equations not only reduces the user's preliminary work in the application of the method, but also reduces the number of time-consuming initial-value problems to be numerically solved at each iteration. For further ease of application, the solution of the overdetermined system for the unknown initial conditions is obtained automatically by applying Golub's linear least-squares algorithm. The relative ease of application of the proposed numerical method increases directly as the order of the differential-equation system increases. Hence, the method is especially attractive for the solution of large-order systems. After the method is described, it is applied to a fifth-order problem from boundary-layer theory.
Numerical methods, FORTRAN program and table form for complex integrals evaluation along unit circle in positive direction
Numerical method solution of nonlinear two- point boundary value problem associated with optimum transfer of spacecraft
Numerical method for treating time transient gas lubrication equation
A numerical method for calculating the time-average, vertical temperature structure of planetary atmospheres is presented. It is assumed that the atmospheres are in radiative-convective equilibrium, which is a good first approximation to many situations. Numerical tests of the rate of convergence and accuracy of the answer are presented. The method can readily handle molecular sources of opacity. Accurate results can be obtained with a minimum of computer time, because the number of iterations needed (about 4) is small and the number of pressure levels at which the net flux needs to be evaluated (about 10) is small. As an application of this procedure, some model atmospheres of Jupiter are calculated.
Numerical method for reducing data from thick calorimeter to determine heating rate to calorimeter surface
Numerical method for rocket trajectory determination from multistation Doppler tracking data
Numerical methods for mixed boundary value problem of axisymmetric shells of revolution, using truncated series expansion and finite difference expressions
Numerical method for calculating near field sonic room pressure signatures and application to high speed digital computer programming
Explicit numerical methods for integrating coupled nonlinear ordinary differential equations with parasitic eignevalues
Numerical method for evaluation and utilization of supersonic nacelle-wing interference
Numerical method to obtain pressure distribution on arbitrary wing planform of various surface shapes with attention to aerodynamic characteristics
Time-dependent numerical method for blunt body flow field solutions