We study a boundary value problem in subsonic aeroelasticity and introduce the cofinite Hilbert transform as a tool in solving an auxiliary linear integral equation on the complement of a finite interval on the real line R.

Scientific problems related to modern aeronautical engineering and dealing with basic properties of shear flows and the associated fluid mechanics phenomena are emphasized. In this context some recent experimental results on subsonic aerodynamics are considered.

Hydrogen may substitute traditional hydrocarbon fuels in propeller and jet aircraft. In the case of propulsion, use combustion engines is preferable to fuel cells plus electric motors. The conversion efficiency from chemical mechanical energy at larger with cells, but propulsion system also larger, addition heavier. Fuel have a better appeal for novel urban air mobility solutions. Hybridization...

An adaptive control system using extremum-seeking optimization is developed to suppress subsonic cavity flow oscillations. The overall control system is developed by following two steps. First, a simple linear control law which uses measurements of wall pressure fluctuations at two different locations in the cavity is developed, and the effect on the magnitude of the limit cycle produced by tun...

Accounting for the Reynolds number is critical in numerical simulations of turbulence, particularly for subsonic flow. For Smoothed Particle Hydrodynamics (SPH) with constant artificial viscosity coefficient α, it is shown that the effective Reynolds number in the absence of explicit physical viscosity terms scales linearly with the Mach number — compared to mesh schemes, where the effective Re...

This paper presents results from investigations of chemically reacting flowfields and optical gain profiles in HF chemical laser media by infrared hyperspectral imaging. Subsonic and supersonic chemiluminescent F+H2 reacting flowfields, produced in high-fluence microwave-driven reactors, were imaged at a series of wavelengths, 2.6-3.1 microm, by a low-order, spectrally scanning Fabry-Perot inte...

A review of wind accretion in high-mass X-ray binaries is presented. We focus attention to different regimes of quasi-spherical accretion onto the neutron star: the supersonic (Bondi) accretion, which takes place when the captured matter cools down rapidly and falls supersonically toward NS magnetospghere, and subsonic (settling) accretion which occurs when plasma remains hot until it meets the...

Noise generation in a subsonic round jet is studied by a simplified model, in which nonlinear interactions of spatially evolving instability modes lead to the radiation of sound. The spatial mode evolution is computed using linear parabolized stability equations. Nonlinear interactions are found on a mode-by-mode basis and the sound radiation characteristics are determined by solution of the Li...