Torsion Galloping of Elongated Bluff Cross Sections

2002 ◽  
Author(s):  
Allan Larsen
Keyword(s):  
Experimental Study ◽  
Cross Sections ◽  
Body Surface ◽  
Vortex Structures ◽  
The Body ◽  
Fluid Stream ◽  
Sign Reversal ◽  
Moment Coefficient ◽  
Coherent Vortex ◽  
The Moment

Torsion galloping of slender structures in a fluid stream is often attributed to a sign reversal of the moment slope, i.e. the moment coefficient attains increasingly negative values with increasing positive angles of attack or visa versa. A numerical and experimental study has revealed that torsion galloping of certain bluff elongated cross sections can not be attributed solely to moment slope reversal but rather the formation and drift of large coherent vortex structures along the body surface.

Variable Reynolds Number Experimental Study on Aerodynamic Characteristic of Supercritical Airfoil RAE2822

2013 ◽  
Vol 420 ◽  
pp. 42-46
Author(s):  
Na Wang ◽  
Chao Gao
Keyword(s):  
Experimental Study ◽  
Reynolds Number ◽  
Wind Tunnel ◽  
Pressure Distribution ◽  
Pressure Coefficient ◽  
Lower Surface ◽  
Number Range ◽  
Moment Coefficient ◽  
Pressure Distributions ◽  
The Moment

An experimental study of pressure distributions over RAE2822 airfoil in the two-dimensional test section 0.8×0.4 meter of a transonic wind tunnel which is the first pressruized continuous wind tunnel in China is presented. This paper in order to further study the influence of the dynamic of continuous changes Reynolds number at Mach number is 0.66 and 0.80, and the attack angle is from-2 degree to 10 degree, and especially the Reynolds number range from3.0×106to 12×106. The study is focalized on the subsonic range of flow conditions with separation and shock wave in the boundary layer. The influence of pressure distribution and pressure coefficient and moment coefficient caused by Reynolds number increasing are analyzed and discussed. The conclusions showed that the pressure distribution of the lower surface of the airfoil get the influence of the Reynolds number is negligible. The Reynolds number impact on the pressure distribution is faintness at Ma=0.66. Reynolds number increases affect the airfoil central and trailing edge pressure. As the Reynolds number increases, the CL curve move and the gradient increasing. The moment coefficient decreased as the Reynolds number increasing. The CL curve with Cd curve moves left as Reynolds number increasing.

scholarly journals APPROACHES TO TRACHEOSTOMY IN PATIENTS WITH DEEP NECK BURNS AND INHALATION INJURY

2018 ◽  
Vol 177 (4) ◽  
pp. 52-55
Author(s):  
V. A. Porhanov ◽  
D. O. Vagner ◽  
S. B. Bogdanov ◽  
E. V. Zinoviev ◽  
I. V. Shlyk
Keyword(s):  
Body Surface ◽  
Inhalation Injury ◽  
The Body ◽  
New Method ◽  
Anterior Surface ◽  
Early Recovery ◽  
The Moment

The OBJECTIVE is to evaluate the results of introduction of the new method of preparation in patients with deep neck  burns to the imposition of tracheostomy. MATERIAL AND METHODS. The study included 124 patients with extensive  deep burns and inhalation injury. The method of treatment consisted of early (3–4 days from the moment of injury)  necrectomy with simultaneous autodermoplasty in the projection of the anterior surface of the neck and torso on the area  of 1–1.5% of the body surface. Tracheostomy was performed after graft engraftment. RESULTS. According to the proposed  method, 20 patients were operated. 17 of them were subjected tracheostomy through the restored skin on 11.6±1.8 days.  CONCLUSION. The method of the early recovery of th skin in the projection of tracheostomy in patients with deep burns  of the neck allows to safely subject tracheostomy through the restored skin on 8–14 days from the moment of the burn.

Frictional Resistance of Enclosed Rotating Cones With Superposed Throughflow

1979 ◽  
Vol 101 (2) ◽  
pp. 259-264 ◽  
Author(s):  
Y. Yamada ◽  
M. Ito
Keyword(s):  
Experimental Study ◽  
Frictional Resistance ◽  
The Other ◽  
Appreciable Effect ◽  
Moment Coefficient ◽  
Rate Of Increase ◽  
Rotating Cone ◽  
Cone Vertex ◽  
The Moment ◽  
Conical Casing

The research summarized in this paper is an experimental study of the frictional moment on a cone rotating in a conical casing with an outward throughflow. The cone vertex angles tested in the present experiment are θ = 30, 60 and 90 deg. In the region where the frictional moment on the rotating cone with no throughflow is increased by the effect of Taylor-type vortices, an increase of the throughflow rate results in a decrease of the frictional moment, if the throughflow rate is not so large. In the region where the Taylor-type vortices have no appreciable effect on the frictional moment, on the other hand, the rate of increase in CM with increasing Cq. sin (θ/2) is almost independent of θ, where CM and Cq denote the moment coefficient and the dimensionless throughflow rate, respectively.

Gender determination of caucasoid hair using image analysis

1993 ◽  
Vol 51 ◽  
pp. 216-217
Author(s):  
T.B. Ball ◽  
W.M. Hess
Keyword(s):  
Image Analysis ◽  
Cross Sections ◽  
Scalp Hair ◽  
The Body ◽  
Equivalent Diameter ◽  
Cross Sectional ◽  
Hair Samples ◽  
Length Width ◽  
Morphological Differences

It has been demonstrated that cross sections of bundles of hair can be effectively studied using image analysis. These studies can help to elucidate morphological differences of hair from one region of the body to another. The purpose of the present investigation was to use image analysis to determine whether morphological differences could be demonstrated between male and female human Caucasian terminal scalp hair.Hair samples were taken from the back of the head from 18 caucasoid males and 13 caucasoid females (Figs. 1-2). Bundles of 50 hairs were processed for cross-sectional examination and then analyzed using Prism Image Analysis software on a Macintosh llci computer. Twenty morphological parameters of size and shape were evaluated for each hair cross-section. The size parameters evaluated were area, convex area, perimeter, convex perimeter, length, breadth, fiber length, width, equivalent diameter, and inscribed radius. The shape parameters considered were formfactor, roundness, convexity, solidity, compactness, aspect ratio, elongation, curl, and fractal dimension.

The Role of Computer Modeling in Electrocardiography

1990 ◽  
Vol 29 (04) ◽  
pp. 282-288 ◽  
Author(s):  
A. van Oosterom
Keyword(s):  
Electrical Activity ◽  
Computer Modeling ◽  
Body Surface ◽  
Electrical Current ◽  
The Body ◽  
Volume Conductor ◽  
Current Generator ◽  
Cardiac Electrical Activity ◽  
Source Models

AbstractThis paper introduces some levels at which the computer has been incorporated in the research into the basis of electrocardiography. The emphasis lies on the modeling of the heart as an electrical current generator and of the properties of the body as a volume conductor, both playing a major role in the shaping of the electrocardiographic waveforms recorded at the body surface. It is claimed that the Forward-Problem of electrocardiography is no longer a problem. Several source models of cardiac electrical activity are considered, one of which can be directly interpreted in terms of the underlying electrophysiology (the depolarization sequence of the ventricles). The importance of using tailored rather than textbook geometry in inverse procedures is stressed.

The use of Body Surface Index as a Better Clinical Health indicators Compare to Body Mass Index and Body Surface Area for Clinical Application

2018 ◽  
pp. 131-136
Author(s):  
Shirazu I. ◽  
Theophilus. A. Sackey ◽  
Elvis K. Tiburu ◽  
Mensah Y. B. ◽  
Forson A.
Keyword(s):  
Surface Area ◽  
Body Surface Area ◽  
Clinical Application ◽  
Body Surface ◽  
Body Height ◽  
Health Indicators ◽  
The Body ◽  
Body Parameters ◽  
The Relationship ◽  
Individual Body

The relationship between body height and body weight has been described by using various terms. Notable among them is the body mass index, body surface area, body shape index and body surface index. In clinical setting the first descriptive parameter is the BMI scale, which provides information about whether an individual body weight is proportionate to the body height. Since the development of BMI, two other body parameters have been developed in an attempt to determine the relationship between body height and weight. These are the body surface area (BSA) and body surface index (BSI). Generally, these body parameters are described as clinical health indicators that described how healthy an individual body response to the other internal organs. The aim of the study is to discuss the use of BSI as a better clinical health indicator for preclinical assessment of body-organ/tissue relationship. Hence organ health condition as against other body composition. In addition the study is `also to determine the best body parameter the best predict other parameters for clinical application. The model parameters are presented as; modeled height and weight; modelled BSI and BSA, BSI and BMI and modeled BSA and BMI. The models are presented as clinical application software for comfortable working process and designed as GUI and CAD for use in clinical application.

Differenzierungen im Begriff, Gegenwart‘ bei Husserl und Merleau-Ponty

2017 ◽  
Vol 2017 (1) ◽  
pp. 39-54
Author(s):  
Jörg Zimmer
Keyword(s):  
Modern Philosophy ◽  
The Body ◽  
Fundamental Concept ◽  
Phenomenological Description ◽  
Philosophy Of Time ◽  
Phenomenology Of Perception ◽  
The World ◽  
Classical Philosophy ◽  
The Moment ◽  
Empty Time

In classical philosophy of time, present time mainly has been considered in its fleetingness: it is transition, in the Platonic meaning of the sudden or in the Aristotelian sense of discreet moment and isolated intensity that escapes possible perception. Through the idea of subjective constitution of time, Husserl’s phenomenology tries to spread the moment. He transcends the idea of linear and empty time in modern philosophy. Phenomenological description of time experience analyses the filled character of the moment that can be detained in the performance of consciousness. As a consequence of the temporality of consciousness, he nevertheless remains in the temporal conception of presence. The phenomenology of Merleau-Ponty, however, is able to grasp the spacial meaning of presence. In his perspective of a phenomenology of perception, presence can be understood as a space surrounding the body, as a field of present things given in perception. Merleau-Ponty recovers the ancient sense of ‘praesentia’ as a fundamental concept of being in the world.

scholarly journals An experimental study of the motion of ice past obstacles by the process of regelation

1976 ◽  
Vol 17 (75) ◽  
pp. 79-98 ◽  
Author(s):  
E. M. Morris
Keyword(s):  
Thermal Conductivity ◽  
Experimental Study ◽  
Cross Sections ◽  
Transition Point ◽  
Water Layer ◽  
Single Object ◽  
Two Systems ◽  
Basal Sliding

AbstractThe results of regelation experiments, in which a single object is pulled through ice, cannot be applied directly to the problem of basal sliding in glaciers because the two systems have different geometries. When the force applied to a single object is small, impurities trapped in the regelation water-layer around the object inhibit the regelation process. At larger forces, above the Drake-Shreve transition point, impurities are shed in a trace behind the object. However, when ice moves over a series of obstacles a trace may exist above and below the transition point. The regelation velocity below the transition point is not reduced by the effect of trapped impurities. In an experiment in which brass cylingerrs of various cross-sections rotate in ice, the ratio between the expected regelation velocity, calculated using the basal-sliding theory of Nye, and the measured regelation velocity is 8±2, both above and below the transition point. The same ratio has been obtained by other workers with wires of similar thermal conductivity above the transition point. Measurements of température differences indicate that supercooling cannot be the main source of the unexpectedly low regelation velocities above the transition point.

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