Numerical solution of nonlinear equations for spinning shallow spherical shells
Nonlinear spinning shallow spherical shell equations solved for equilibrium stress and displacement distributions, discussing inertia loading
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Nonlinear spinning shallow spherical shell equations solved for equilibrium stress and displacement distributions, discussing inertia loading
Hybrid satellite attitude control system deformation model, utilizing pivoted flexible boom with tip mass as actuator and inertia wheels to dampen gravity induced librations
Temperature distribution in shadowed lunar craters formulated in Fredholm integral equations, showing constant temperature and correction for soil thermal inertia
Long wave approximation for peristaltic transport in circular cylindrical tube, noting inertia and wavelength effects on backward flow
Gearing system for eliminating backlash and filtering input torque fluctuations from high inertia load
Low-inertia flow-direction vane static and dynamic wind tunnel tests at subsonic and supersonic speeds for in-flight measurement of bust velocities
Axisymmetric flows with regions of closed streamlines confined by rotational inertia or electromagnetic pinch, for containment for gas core reactors
Neutron star matter equations of state involving hyperon formation effects for maximal stable mass models, tabulating moments of inertia
Thin conical shell under longitudinal impact, deriving theory for transverse and rotary inertias and transverse shear deformation effects
Compressible flow across shaft face seals and narrow slots, examining fluid inertia, viscous friction and entrance losses
Compressor raises pressure of gases from low ambient supply during space experiments by a system of low weight, size, and power input. Dc rotary-torque motor and ball-screw drive shaft activate first and second stage of compressor, utilizing inertia forces to operate check valves.
Electromagnetic wave enters reflector array consisting of grid work of metallic reflectors with each reflector obscuring a portion of its neighbors to prevent direct passage of wave through grid. Antenna movement involves reduced amplitude of angular motion and internal concellations of translational and rotational inertias.
Shoulder-harness and lap-belt restraint system was designed to be worn by individuals of widely different sizes and to permit normal body motion except under sudden deceleration. System is divided into two basic assemblies, lap belt and torso or shoulder harness. Inertia-activated reels immediately lock when seat experiences sudden deceleration.
A fixed-base piloted simulator investigation has been made of the feasibility of using any of several manual guidance and control techniques for emergency lunar escape to orbit with very simplified, lightweight vehicle systems. The escape-to-orbit vehicles accommodate two men, but one man performs all of the guidance and control functions. Three basic attitude-control modes and four manually executed trajectory-guidance schemes were used successfully during approximately 125 simulated flights under a variety of conditions. These conditions included thrust misalinement, uneven propellant drain, and a vehicle moment-of-inertia range of 250 to 12,000 slugs per square foot. Two types of results are presented - orbit characteristics and pilot ratings of vehicle handling qualities.
Analytical and experimental investigations of a pilot model of a channel for the study of two-phase flow under low or zero gravity are presented. The formulation of dimensionless parameters to indicate the relative magnitude of the effects of capillarity, gravity, pressure gradient, viscosity, and inertia is described. The investigation is based on the principal equations of fluid mechanics and thermodynamics. Techniques were investigated by using a laser velocimeter for measuring point velocities of the fluid within the porous material without disturbing the flow.
A mathematical model derived from the equation of heat conduction was developed to assist in interpreting thermal infrared images acquired from aircraft and spacecraft. The model assumes steady state boundary conditions. It contains parameters of rock and soil properties, atmospheric effects, site location, and season. The results predicted provide an explanation for the thermal differences among granite, limestone, and dolomite recorded in the December 1968 daytime and predawn flights over the Mill Creek, Oklahoma test site, during which representative thermal inertia and albedo values were used. A second test of the model made use of data acquired during the June 1970 predawn overflight of Mill Creek. A simple model of transient heating of the ground was constructed as an extension of the overall model, in order to examine the effects of atmospheric perturbations. The results obtained are consistent with those of ground observations made at the time of the overflight.
The equations for the motion, forces, and couples generated by clamshells released from spinning sounding rockets in accordance with a roll-out ejection concept are presented. The application of these equations to a study of a system for the Javelin rocket vehicle is discussed. The roll-out ejection concept advocated requires that each deploying clamshell be pivoted about an axis at its trailing edge located in the system sectioning plane. Clamshell despinning is a consequence of this deployment since the pivotal rate is in opposition to the rocket vehicle spin. The energy required by the deployment is derived largely from the rotational energy of the clamshell. Thus, the rocket vehicle will not be significantly despun by this kind of clamshell deployment. This ejection concept also permits a system design which makes it possible to limit clamshell angular motion to rotation about that one of its centroidal principal axes which is brought into parallelism with the rocket vehicle longitudinal axis. Also, by equalizing the moments of inertia about the other centroidal principal axes, the roll-out motion can be decoupled from any extraneous angular motion about these axes.
The power clutch presented is designed for the transfer of electrical signals and power across rotating joints. Radio noise, friction, and wear are virtually eliminated. The design, construction, and applications are discussed. This clutch eliminates the need of recycling solar arrays once each orbit by recycling only a low-inertia component of the power system.