In this paperwe have solved the hydrodynamic equations governing the spherically symmetric isothermal accretion (wind) onto (away from) compact objects using various pseudo-Schwarzschild potentials.These solutions are essentially one parameter solutions in a sense that all relevant dynamical as well as thermodynamic quantities for such a flow could be obtained (with the assumption of a one-temp...

Plasma in the Sun's hot corona expands into the heliosphere as a supersonic and highly magnetized solar wind. This paper provides an overview of our current understanding of how the corona is heated and how the solar wind is accelerated. Recent models of magnetohydrodynamic turbulence have progressed to the point of successfully predicting many observed properties of this complex, multi-scale s...

Massive stars drive powerful, supersonic winds via the radiative momentum associated with the thermal UV emission from their photospheres. Shock phenomena are ubiquitous in these winds, heating them to millions, and sometimes tens of millions, of degrees. The emission line spectra from the shock-heated plasma provide powerful diagnostics of the winds’ physical conditions, which in turn provide ...

Models are presented for the aerodynamic coefficients of Supersonic Ringsail and Disk-Gap-Band parachutes as functions of total porosity, λT, Mach number, M, and total angle of attack, αT (when necessary). The source aerodynamic coefficients data used for creating these models were obtained from a wind tunnel test of subscale parachutes. In this wind tunnel test, subscale parachutes of both par...

In Paper I we showed that steady line-driven disk wind solutions can exist by using “simple” models that mimic the disk environment. Here I extend the concepts introduced in Paper I and discuss many details of the analysis of the steady/unsteady nature of 1D line-driven winds. This work confirms the results and conclusions of Paper I, and is thus consistent with the steady nature of the 1D stre...

We present two-dimensional hydrodynamic models of thermally driven winds from highly irradiated, closein extra-solar planets. We adopt a very simple treatment of the radiative heating processes at the base of the wind, and instead focus on the differences between the properties of outflows in multidimensions in comparison to spherically symmetric models computed with the same methods. For hot (...

In this article, an attempt is made to describe and review the most widely used methods for flow visualization. The first part describes the basis and applications of different visualization methods (non optical) for subsonic and supersonic flow in wind and water tunnels: direct injection methods, (smoke, dye, fog and different small particles) visualization methods by electrolytic and photoche...

Nonintrusive, off-body flow barometry in Mach 2 airflow has been demonstrated in a large-scale supersonic wind tunnel using seedless laser-induced thermal acoustics (LITA). The static pressure of the gas flow is determined with a novel differential absorption measurement of the ultrasonic sound produced by the LITA pump process. Simultaneously, the streamwise velocity and static gas temperature...

Massive binary star systems are not uncommon, and neither the supersonic collision of their winds. In the present work we study these shocks and the further consequences on wind structure. The post-shock gas is a warm and high-density environment, which allows dust to form and grow. We show that this growth is fast, of just a few hours. An application for ηCar shows that, probably, the decline ...