Asymmetrical Lateral Jet Interaction on a Slender Body in Supersonic Flow

2014 ◽  
Vol 565 ◽  
pp. 107-112
Author(s):  
Shi Jie Luo
Keyword(s):  
Supersonic Flow ◽  
Total Pressure ◽  
Angle Of Attack ◽  
The Body ◽  
Slender Body ◽  
Far Field ◽  
Field Interaction ◽  
Jet Interaction ◽  
Pressure Distributions ◽  
Highly Nonlinear

The lateral jet interaction on a slender body with rudders in supersonic flow had been investigated by numerical simulation, when the lateral jet is not in the longitudinal symmetry plane. It was called Asymmetrical lateral jet interaction in this paper. The flow features of jet interaction flowfield on the surface of the body or in the space far from the surface at different angles of attack and total pressure of jet was analyzed. As a result, the lateral jet interaction disturbed the pressure distributions of the slender body, and it was divided into near-field interaction near jet and far-field interaction aft-body on the basis of distance to jet. With the variety of the angle of attack and total pressure of jet, the pressure distributions at the aft-body change tempestuously, thereby the normal and lateral load will be from positive to negative, or reverse. The results also showed that the far-field interaction played a major role in the lateral jet interaction on a slender body in supersonic flow. The far-field interaction was caused by the changing of the outflow direction and intensity. Besides, the force/moment amplification factors presented highly nonlinear with the variety of angle of attack and total pressure of jet.

Numerical Simulation of Lateral Jet Interaction a Slender Body in Supersonic Flow

2013 ◽  
Vol 404 ◽  
pp. 296-301
Author(s):  
Shi Jie Luo ◽  
Yao Feng Liu ◽  
Ning Cao
Keyword(s):  
Supersonic Flow ◽  
Angle Of Attack ◽  
Symmetry Plane ◽  
Slender Body ◽  
Lateral Loads ◽  
Jet Interaction ◽  
Pressure Distributions ◽  
Highly Nonlinear ◽  
Flow Features ◽  
Force Moment

A numerical investigation has been conducted to research the interaction flowfield of lateral jet not in the longitudinal symmetry plane on a slender body with rudders in supersonic flow. The surface and space flow features of jet interaction flowfield with different angles of attack was analyzed. The paper also compared with and without jet interaction flowfield characteristics. As a result, the jet interaction destroys pressure distributions of the slender body, and causes normal and lateral loads. With angle of attack, the pressure distributions of the after body and rudders surfaces are change tempestuously. The results also show that the far-field interference played a major role in the lateral jet interaction. Besides, the force/moment amplification factors present highly nonlinear with angle of attack.

Visualization of asymmetric separation induced by lateral jet interaction on a slender body in supersonic flow

2020 ◽  
Vol 34 (14n16) ◽  
pp. 2040081
Author(s):  
Shi-Jie Luo ◽  
Yao-Feng Liu ◽  
Yu-Wei Liu
Keyword(s):  
Supersonic Flow ◽  
Flow Characteristic ◽  
Symmetry Plane ◽  
Flow Characteristics ◽  
Surface Flow ◽  
Slender Body ◽  
Separation Flow ◽  
Field Interaction ◽  
Jet Interaction ◽  
Pressure Distributions

The lateral jet interaction on a slender body in supersonic flow was investigated by numerical simulation. The spatial and surface flow characteristics induced by jet interaction were shown. As a result, when the lateral jet is not in the longitudinal symmetry plane, the jet interaction causes asymmetric separation flow of surface and space, and destroys the pressure distributions of the slender body. With different angle of attack and circumferential positions of jet, the flow characteristic of the after body for jet in asymmetry plane changes greatly. The results with and without jet interaction also show that the far-field interaction played a major role in the lateral jet interaction.

Two-Dimensional Boat-Tailed Bases in Supersonic Flow

1974 ◽  
Vol 25 (3) ◽  
pp. 210-224 ◽  
Author(s):  
P R Viswanath ◽  
R Narasimha
Keyword(s):  
Boundary Layer ◽  
Supersonic Flow ◽  
Free Stream ◽  
The Body ◽  
Base Pressure ◽  
Two Dimensional ◽  
Sharp Corner ◽  
Boundary Layer Effect ◽  
Pressure Distributions ◽  
Layer Effect

SummaryBoat-tailing of aft bodies may affect the base pressure through two mechanisms: firstly by changing the angle between the approaching flow at separation and the reattachment surface, and secondly by distorting the boundary layer through the favourable pressure gradient (which can be particularly severe in the presence of a sharp corner on the body). The first effect is isolated here by tests on inclined backward-facing steps with a fully developed turbulent boundary layer at separation, at free-stream Mach numbers of 1.75 and 2.4. It is found that the base pressure increases significantly with boat-tail angle; the data have been correlated taking explicit account of the boundary layer effect, modifying and extending the approach adopted by Nash. Charts are provided for quick estimation of base pressure in engineering calculations. Some of the earlier data on boat-tailed bases, on re-examination in the light of the present correlation, suggest that strongly distorted boundary layers at separation affect the base pressure appreciably. Several features of the measured reattachment pressure distributions, including their internal similarity, are also discussed.

The Flow and Interference Effects of a Body of Revolution and Its Stabilizing Surfaces When at a Small Angle of Attack

1965 ◽  
Vol 87 (4) ◽  
pp. 941-952
Author(s):  
E. J. Rodgers
Keyword(s):  
Velocity Field ◽  
Angle Of Attack ◽  
Surface Flow ◽  
The Body ◽  
Body Of Revolution ◽  
Interference Effects ◽  
Measured Velocity ◽  
Pressure Distributions ◽  
Flow Effects ◽  
Real Flow

The flow over a body of revolution and its stabilizing surfaces, at an angle of attack, was studied experimentally in order to obtain a better understanding of the real-flow effects as well as the interference effects between components of the configuration. The velocity field about the configuration, the surface flow, and the pressure distribution were obtained with the model mounted in the wind tunnel of the Ordnance Research Laboratory. Analysis of the data showed there is an increase in lift on the body and a decrease in lift on the stabilizing surfaces from that of the isolated components at the same incidence to the flow. The interference effects between components is evidenced by the surface flows and pressure distributions as well as the vorticity distribution calulated from the measured velocity field. The decreased lift on the stabilizing surfaces is clearly related to the flow over the after part of the body.

scholarly journals Preliminary Study on Aerodynamic Control of High-Angle-of-Attack Slender Body Using Blowing from Penetrating Flow Channels

2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Ayane Sato ◽  
Hiroyuki Nishida ◽  
Satoshi Nonaka
Keyword(s):  
Angle Of Attack ◽  
Surface Flow ◽  
The Body ◽  
Slender Body ◽  
High Angle ◽  
Control Effect ◽  
High Angle Of Attack ◽  
Separation Line ◽  
Flow Channels ◽  
Aerodynamic Control

The objective of this study is to experimentally verify a new aerodynamic control concept of a high-angle-of-attack slender body. In the concept, penetrating flow channels are installed to the apex of the slender body. The blowing or suction is generated at the channel exits in response to the surface pressure distribution. First, the effects of the flow channels on the aerodynamic characteristics are experimentally investigated in a low-speed wind tunnel. The result shows the Suction-Blowing type channel is the most effective because its control effect does not reduce even in higher mainstream flow velocity. The peak value of the side force and yawing moment can be reduced by up to 64% and 49%, respectively. In addition, visualization of the surface flow pattern by the oil flow method shows that the Suction-Blowing type channel makes not only the primary separation line on the body side but also the secondary separation line on the body back become symmetric.

Incompressible potential flow past ‘not-so-slender’ bodies of revolution at an angle of attack

1975 ◽  
Vol 70 (4) ◽  
pp. 651-661 ◽  
Author(s):  
P. Sivakrishna Prasad ◽  
N. R. Subramanian
Keyword(s):  
Velocity Potential ◽  
Angle Of Attack ◽  
The Body ◽  
Virtual Mass ◽  
Bodies Of Revolution ◽  
Exact Theory ◽  
Pressure Distributions ◽  
Ellipsoid Of Revolution ◽  
Slender Bodies ◽  
Good Agreement

Using the method of matched asymptotic expansions, an expansion of the velocity potential for steady incompressible flow has been obtained to order ε4for slender bodies of revolution at an angle of attack by representing the potential due to the body as a superposition of potentials of sources and doublets distributed along a segment of the axis inside the body excluding an interval near each end of the body. Also, expansions of the coefficients of longitudinal virtual mass and lateral virtual mass have been found. The pressure distributions over an ellipsoid of revolution of thickness ratio ε = 0·3 at zero angle of attack and at an angle of attack of 3° obtained by the present method are compared with results obtained from the exact theory and that of Van Dyke. The virtual-mass coefficients are also compared with those obtained from the exact theory and are found to be in good agreement up to ε = 0·3.

A Combination of the Quasi-Cylinder and Slender Body Theories

1955 ◽  
Vol 59 (532) ◽  
pp. 305-308 ◽  
Author(s):  
C. H. E. Warren ◽  
L. E. Fraenkel
Keyword(s):  
Point Of View ◽  
The Body ◽  
Slender Body ◽  
Maximum Diameter ◽  
Slender Body Theory ◽  
Bodies Of Revolution ◽  
Pressure Distributions ◽  
Simple Body ◽  
Body Theory ◽  
Supersonic Flow Past Bodies

The Quasi-Cylinder and slender body theories for the supersonic flow past bodies of revolution have been much used in recent years because, for reasonably simple body profiles, these theories permit a simple and rapid calculation of the first-order pressure distributions and aerodynamic forces. It is assumed in both theories that the body profile slope is small; in the quasi-cylinder theory it is also assumed that the body radius is nearly constant, whereas in the slender body theory it is assumed that the thickness ratio of the body (maximum diameter/length) is small.In the present note these two theories are combined completely. From a strictly mathematical point of view nothing is gained by this combination, and, furthermore,application of the combined theory to a particular case is in general a little more laborious than application of either of the original theories.

Men’s Hunger, Food Consumption, and Preferences for Female Body Types

2014 ◽  
Vol 45 (6) ◽  
pp. 495-497 ◽  
Author(s):  
Nicolas Guéguen
Keyword(s):  
Food Consumption ◽  
Female Body ◽  
The Body ◽  
Slender Body ◽  
Mediation Effect ◽  
Point Scale ◽  
Body Type ◽  
Experimental Conditions

Nelson and Morrison (2005 , study 3) reported that men who feel hungry preferred heavier women. The present study replicates these results by using real photographs of women and examines the mediation effect of hunger scores. Men were solicited while entering or leaving a restaurant and asked to report their hunger on a 10-point scale. Afterwards, they were presented with three photographs of a woman in a bikini: One with a slim body type, one with a slender body type, and one with a slightly chubby body. The participants were asked to indicate their preference. Results showed that the participants entering the restaurant preferred the chubby body type more while satiated men preferred the thinner or slender body types. It was also found that the relation between experimental conditions and the choices of the body type was mediated by men’s hunger scores.

The Supersonic Flow Past a Slender Ducted Body of Revolution with an Annular Intake

1950 ◽  
Vol 1 (4) ◽  
pp. 305-318
Author(s):  
G. N. Ward
Keyword(s):  
Supersonic Flow ◽  
Velocity Potential ◽  
Operational Calculus ◽  
The Body ◽  
Body Of Revolution ◽  
Internal Flows ◽  
Flow Past ◽  
External Forces ◽  
Internal Pressures ◽  
Slender Body Of Revolution

SummaryThe approximate supersonic flow past a slender ducted body of revolution having an annular intake is determined by using the Heaviside operational calculus applied to the linearised equation for the velocity potential. It is assumed that the external and internal flows are independent. The pressures on the body are integrated to find the drag, lift and moment coefficients of the external forces. The lift and moment coefficients have the same values as for a slender body of revolution without an intake, but the formula for the drag has extra terms given in equations (32) and (56). Under extra assumptions, the lift force due to the internal pressures is estimated. The results are applicable to propulsive ducts working under the specified condition of no “ spill-over “ at the intake.

scholarly journals Investigation on Wireless Link for Medical Telemetry Including Impedance Matching of Implanted Antennas

Sensors ◽  
2021 ◽  
Vol 21 (4) ◽  
pp. 1431
Author(s):  
Ilkyu Kim ◽  
Sun-Gyu Lee ◽  
Yong-Hyun Nam ◽  
Jeong-Hae Lee
Keyword(s):  
Real Time ◽  
Human Body ◽  
Near Field ◽  
Impedance Matching ◽  
The Body ◽  
Field Pattern ◽  
Communication Link ◽  
Far Field ◽  
Antenna Coupling ◽  
Medical Telemetry

The development of biomedical devices benefits patients by offering real-time healthcare. In particular, pacemakers have gained a great deal of attention because they offer opportunities for monitoring the patient’s vitals and biological statics in real time. One of the important factors in realizing real-time body-centric sensing is to establish a robust wireless communication link among the medical devices. In this paper, radio transmission and the optimal characteristics for impedance matching the medical telemetry of an implant are investigated. For radio transmission, an integral coupling formula based on 3D vector far-field patterns was firstly applied to compute the antenna coupling between two antennas placed inside and outside of the body. The formula provides the capability for computing the antenna coupling in the near-field and far-field region. In order to include the effects of human implantation, the far-field pattern was characterized taking into account a sphere enclosing an antenna made of human tissue. Furthermore, the characteristics of impedance matching inside the human body were studied by means of inherent wave impedances of electrical and magnetic dipoles. Here, we demonstrate that the implantation of a magnetic dipole is advantageous because it provides similar impedance characteristics to those of the human body.

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