541 research outputs found
Stochastic modeling of the time-averaged equations for climate dynamics
Two analyses on climate dynamics are presented, both based on a simplified set of barotropic equations for representing large scale non-linear atmospheric circulation characteristics. The statistical properties of the set of equations were investigated for small values of a parameter k sub o, corresponding to the physical case of large zonal westerlies and relatively weak eddy motions. The effect of seasonal type forcing on the solution of these equations was also studied and some preliminary numerical results are presented
Magnetohydrodynamic and gasdynamic aspects of solar-wind flow around terrestrial planets: A critical review
Problems in space physics are discussed whose models, in simplified form, reduce to a supersonic flow scheme with a detached shock wave, namely: (1) solar wind interaction with an intrinsic planetary magnetic field; (2) solar wind interaction with the ionized component of the atmosphere of a comet; and (3) solar wind interaction with the ionosphere of a planet which does not possess its own magnetic field. The numerical study of the above problems is performed with the use of magnetogasdynamic equations for an ideal single fluid model. From the physical veiwpoint, the problems are solved in terms of as simple phenomena as possible; the principal objective is to make recently developed methods of numerical analysis of mixed flows applicable to space physics problems
Theoretical Determination of the Boundary of the Geomagnetic Field in a Steady Solar Wind
Theoretical determination of the boundary of the geomagnetic field in a steady solar win
Note on models of the propagation of solar flare plasma through interplanetary space
Theoretical treatment of propagation of solar flare disturbance in interplanetary spac
Theoretical Investigation of Submerged Inlets at Low Speeds
The general characteristics of the flow field in a submerged air inlet are investigated by theoretical, wind-tunnel, and visual-flow studies. Equations are developed for calculating the laminar and turbulent boundary-layer growth along the ramp floor for parallel, divergent, and convergent ramp walls, and a general equation is derived relating the boundary-layer pressure losses to the boundary-layer thickness. It is demonstrated that the growth of the boundary layer on the floor of the divergent-ramp inlet is retarded and that a vortex pair is generated in such an inlet. Functional relationships are established between the pressure losses in the vortices and the geometry of the inlet. A general discussion of the boundary layer and vortex formations is included, in which variations of the various losses and of the incremental external drag with mass-flow ratio are considered. Effects of compressibility are also discussed
Magnetohydrodynamic and gasdynamic theories for planetary bow waves
A bow wave was previously observed in the solar wind upstream of each of the first six planets. The observed properties of these bow waves and the associated plasma flows are outlined, and those features identified that can be described by a continuum magnetohydrodynamic flow theory. An account of the fundamental concepts and current status of the magnetohydrodynamic and gas dynamic theories for solar wind flow past planetary bodies is provided. This includes a critical examination of: (1) the fundamental assumptions of the theories; (2) the various simplifying approximations introduced to obtain tractable mathematical problems; (3) the limitations they impose on the results; and (4) the relationship between the results of the simpler gas dynamic-frozen field theory and the more accurate but less completely worked out magnetohydrodynamic theory. Representative results of the various theories are presented and compared
Interplanetary space-A new laboratory for rarefied gas dynamics
Interplanetary space provides simultaneously the best vacuum available to man and, because of the solar wind, a tenuous and unsteady high-speed outflow of predominantly hydrogen gas from the sun, a remarkable variety of rarefied gasdynamics phenomena, to observe. A review is provided of these phenomena, and of the way in which the present level of understanding has been achieved
Calculative techniques for transonic flows about certain classes of wing-body combinations, phase 2
Theoretical analysis and associated computer programs were developed for predicting properties of transonic flows about certain classes of wing-body combinations. The procedures used are based on the transonic equivalence rule and employ either an arbitrarily-specified solution or the local linerization method for determining the nonlifting transonic flow about the equivalent body. The class of wind planform shapes include wings having sweptback trailing edges and finite tip chord. Theoretical results are presented for surface and flow-field pressure distributions for both nonlifting and lifting situations at Mach number one
Calculation of solar wind flows about terrestrial planets
A computational model was developed for the determination of the plasma and magnetic field properties of the global interaction of the solar wind with terrestrial planetary magneto/ionospheres. The theoretical method is based on an established single fluid, steady, dissipationless, magnetohydrodynamic continuum model, and is appropriate for the calculation of supersonic, super Alfvenic solar wind flow past terrestrial planets. A summary is provided of the important research results
Development of a computational model for predicting solar wind flows past nonmagnetic terrestrial planets
A computational model for the determination of the detailed plasma and magnetic field properties of the global interaction of the solar wind with nonmagnetic terrestrial planetary obstacles is described. The theoretical method is based on an established single fluid, steady, dissipationless, magnetohydrodynamic continuum model, and is appropriate for the calculation of supersonic, super-Alfvenic solar wind flow past terrestrial ionospheres
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