Experimental investigation of the interaction of a plane, oblique, incident-reflecting shock wave with a turbulent boundary layer on a cooled surface. Volume 1 - Test description and data summary

Interaction of plane, oblique, incident reflecting shock wave with turbulent boundary layer on cooled surface - summar

STOL landing thrust: Reverser jet flowfields

Analysis tools and modeling concepts for jet flow fields encountered upon use of thrust reversers for high performance military aircraft are described. A semi-empirical model of the reverser ground wall jet interaction with the uniform cross flow due to aircraft forward velocity is described. This ground interaction model is used to demonstrate exhaust gas ingestion conditions. The effects of control of exhaust jet vector angle, lateral splay, and moving versus fixed ground simulation are discussed. The Adler/Baron jet-in-cross flow model is used in conjunction with three dimensional panel methods to investigate the upper surface jet induced flow field

Investigation of impingement region and wall jets formed by the interaction of high aspect ratio lift jets and a ground plane

Flow characteristics of impinging jets emanating from rectangular exit area converging nozzles of exit area aspect ratio four, six, and eight were investigated. Azimuthal distributions of wall jet radial momentum flux in the ground plane were strongly directional and sensitive to rectangular nozzle exit area aspect ratio, jet impingement angle, and height above ground, H/D. Effects of jet exit velocity profile nonuniformities were also investigated. Data from the single nozzle rectangular jet impringement investigations were incorporated into an existing VTOL aircraft ground flow field computer program. It is suggested that this program together with the Douglas Neumann program modified for V/STOL applications may be used for the analysis and prediction of flow fields and resulting forces and moments on multijet V/STOL aircraft hovering in ground effect

Thin airfoils in rotational flow

September 1965Also issued as: Massachusetts Institute of Technology. Dept. of Mechanical Engineering. Thesis. 1966. Sc.DIncludes bibliographical references (leaves 88-90)The problem of rotational or shear flow about thin airfoils has been investigated theoretically and experimentally. The theoretical approach is based on the concept of a lifting line in a bounded shear flow whose primary flow velocity profile may be expressed in terms of elementary linear, hyperbolic, and / or circular functions. The solution of the linearized equations of motion is reduced to the solution of a characteristic value problem whose form is dependent on the geometry of the primary flow. The characteristic value problem is solved for four different velocity profiles including that of a monotonic-matched linear profile ( a layer of constant vorticity fluid bounded by layers of uniform flow ) which serves as a model for the experimental shear flows. The experimental work includes the measurement of local lift coefficients and spanwise lift distributions on thin symmetrical airfoils in monotonic shear flows for three values of the ratio of airfoil chord to shear layer thickness. The results of the lifting line theory show good agreement with the experimental data within the range of applicability, i.e. within the linear region of the CL, a relationship and for flow geometries where the distortion ( spanwise convection ) of the surfaces of constant stagnation pressure is negligible. The assumption that the local lift coefficient is a function only of the local angle of attack and the two-dimensional characteristic of the airfoil section ( a fundamental assumption of lifting line theory ) is investigated experimentally through a consideration of local pressure coefficient distributions. An approximate correction to the lifting line theory is suggested for flows in which the distortion of surfaces of constant stagnation pressure cannot be neglected.Under the sponsorship of General Electric Company, Allison Division of General Motors Corporatio

Le couteau de Bohémond et la thériaque à vilain. La vénénologie savante face aux remèdes “merveilleux” ou “populaires”

Originating in the western world at the end of the 13th century, treatises about poisoning aim to protect patients against poisons or to heal the poisoned. They must be considered as medical writings belonging to scholasticism. But the subject of toxicatio leads the authors to speak about antidotes that seem, at fi rst sight, far from the world of learned medicine because they are linked with “marvels of nature” or with popular culture. After listing those things mentioned by doctors, the paper will try to show why and how they were intellectually integrated in the scientia venenorum.[fr] Éclos en Occident à la fin du XIIIe siècle, les traités des poisons visent à protéger ou soigner les patients des périls ou des effets du poison. Ils se rangent parmi les écritures médicales scolastiques. Mais le domaine de la toxicatio conduit les auteurs à traiter d’antidotes à première vue éloignés des sphères de la médecine savante, soit qu’ils se rattachent aux “merveilles de la nature”, soit qu’ils proviennent de la culture vulgaire. Après avoir inventorié ces anti-poisons mentionnés par les docteurs, l’article s’attachera à montrer pourquoi et comment ils sont intellectuellement intégrés à la scientia venenorum

A gold lamella for ‘Blessed’ Abalala

This article examines a previously unpublished gold lamella of unknown provenance, datable on palaeographical grounds to the 1st century BCE, give-or-take a half century, either side. The tablet preserves three words written in Greek letters that may contain a GrecoPersian formula of protection in the afterlife for its bearer, Abalala, a name of pre-Islamic extraction. The study compares the formula with those on a number of shorter ‘Orphic’ gold lamellae to show that the tiny piece represents a ‘Totenpaß’ for the beneficent dead, rather than a protective charm (phylactery) with the usual voces magicae, although the distinction between magic words and meaningful text is not always clear in such instances