| Experimental Investigation of a Lift Augmented Ground Effect Platform |
SEP 2005 |
108 pages |
| Authors:
Roberto T. Igue; AIR FORCE INST OF TECH WRIGHT-PATTERSONAFB OH SCHOOL OF ENGINEERING
|
 | This experimental study investigated the feasibility of applying the concept of a skirtless hovercraft into the production of an operational vehicle. A 0.255 m diameter prototype was designed, built and tested. An air bearing table was used as a testing platform, virtually eliminating the influence of friction and providing one degree of freedom for the experiments. Static tests were performed at various heights and craft configurations, providing a wide range ... |
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| Characteristics of a Dual-Slotted Circulation Control Wing of Low Aspect Ratio Intended for Naval Hydrodynamic Applications |
31 AUG 2005 |
30 pages |
| Authors:
Ernest O. Rogers; Martin J. Donnelly; NAVAL SURFACE WARFARE CENTER CARDEROCK DIV BETHESDA MD HYDROMECHANICS DIRECTORATE
|
| An experimental investigation was conducted in a water tunnel to explore the application of Coanda-effect circulation control to low aspect ratio wings. The facility was the Large Cavitation Channel in Memphis, TN. The intended application is to high-lift control surfaces (appendages) on underwater naval vehicles. Test results are interpreted in light of both theory and the extensive experience with circulation control (CC) technology at NSWCCD. The semi-span wing test model ... |
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| A Study of a Skirtless Hovercraft Design |
MAY 2004 |
70 pages |
| Authors:
Edward A. Kelleher; AIR FORCE INST OF TECH WRIGHT-PATTERSONAFB OH DEPT OF AERONAUTICS AND ASTRONAUTICS
|
| Initial study into three possible skirtless hovercraft designs. The designs utilize Coanda nozzles and a Coanda wing surface to generate lift and create a pressure cushion below the craft. The pressure cushion is to be maintained by an air curtain created by flow spill from the Coanda wing surface. Three proposed skirtless hovercraft designs were analyzed via computational fluid dynamics to ascertain their lift generation capabilities. The three designs were ... |
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| Dual Cavitating Hydrofoil Structures for Multi-Speed Applications. |
11 FEB 1997 |
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| Authors:
Young T. Shen; DEPARTMENT OF THE NAVY WASHINGTON DC
|
 | A hydrofoil structures for efficient operation over a wide speed range from subcavitating to supercavitating operation is provided. The dualcavitating hydrofoil overcomes cavitation problems associated with high speed operation of prior art subcavitating hydrofoils by providing a supercavitating profile shape in the lower surface to achieve a supercavitating condition at high speeds and overcomes performance related problems associated with low speed operation and structural problems associated with high speed operation ... |
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| Marine Propeller. |
07 NOV 1995 |
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| Authors:
Robert M. Williams; Ernest O. Rogers; Maurice M. Sevik; DEPARTMENT OF THE NAVY WASHINGTON DC
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| A marine propeller using the circulation control principle of blowing tangentially over a Coanda surface at the trailing edge of each blade to develop high blade lift (thrust). Each blade has internal chambers and two blowing slots so that blowing is controllable for forward and for reverse thrust without reversing rotational direction of the propeller. This propeller is capable of generating much greater thrust and ship speed at lower RPM ... |
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| Thrust Vector Control of Rectangular Jets Using Counterflow |
31 AUG 95 |
141 pages |
| Authors:
Michael R. Van der Veer; Paul J. Strykowski; MINNESOTA UNIV MINNEAPOLIS OFFICE OF RESEARCH AND TECHNOLOGY TRANSFER ADMINIS TRATION
|
| Fluidic vectoring of a subsonic jet was examined using a curved countercurrent mixing layer. A rectangular jet having a 4:1 aspect ratio was studied at Mach numbers up to 0.5 at a stagnation temperature of 300 K. Several different curved control surfaces called "collars" were placed downstream of the nozzle exit over which the pressure forces could act to produce jet thrust vectoring. Results showed that by applying counterfiow over ... |
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| Efficiency of Fiber Dispersion |
JUL 93 |
25 pages |
| Authors:
C. W. Bruce; Mike J. Thurston; A. V. Jelinek; ARMY RESEARCH LAB WHITE SANDS MISSILE RANGE NM
|
| Net efficiencies for the dissemination of graphitic fibers are determined for two continuous processes (fibers cut as part of the dispersion process or precut). In both cases an extensive grid of passive dosimetric samplers inset with a coarser grid of time resolved aerosol density samplers provided an absolute time average dosage profile, which was integrated over space to give the total effective airborne aerosol mass. The efficiency is expressed as ... |
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| Aerodynamic Surface Tip Vortex Attenuation System. |
27 OCT 1992 |
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| Authors:
Robert M. Taylor; DEPARTMENT OF THE NAVY WASHINGTON DC
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| Apparatus and method for attenuating fluid foil tip vortices, featuring a 'Coanda tip' and a 'Coanda curtain'. The fluid foil tip has a Coanda surface and means for discharging compressed fluid adjacent thereto; a resultant fluid barrier is formed generally chordwise and perpendicular to the fluid foil plane and tangential to the fluid foil tip upon Coanda entrainment and deflection of the discharged compressed fluid. The fluid barrier prevents crossflow ... |
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| An Experimental Study of a Sting-Mounted Circulation Control Wing |
DEC 91 |
136 pages |
| Authors:
Steven J. Lacher; AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH SCHOOL OF ENGINEERING
|
| This wind tunnel study investigated the lift, drag, and pitching moment of a 20% thick, 8.5% camber, partial elliptical cross-section, single blowing slot, 2.325 aspect ratio, rectangular circulation control wing. The AFIT 5-foot wind tunnel was used. Lift and drag were referenced to the wind axis. The Reynolds number was 500,000 for all tests. Angle of attack was varied from -6 to 16 degrees and the effects of pulsed blowing ... |
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| Optimal Control of Lift/Drag Ratio on a Rotating Cylinder |
JUN 91 |
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| Authors:
Yuh-Roung Ou; John A. Burns; INSTITUTE FOR COMPUTER APPLICATIONS IN SCIENCE AND ENGINEERING HAMPTON VA
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| A Literature Search and Evaluation of Angled Wall Jet Deflection |
JUN 91 |
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| Authors:
Peter R. Witting; H. J. Sneck; ARMY ARMAMENT RESEARCH DEVELOPMENT AND ENGINEERING CENTER WATERVLIET NY BENET LABS
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| It has been suggested that the direction and shape of bore evacuator jets can be affected by the angle the evacuator holes make with the tube wall. A literature search was conducted to discover and evaluate what is known about the deflection of wall jets. Preliminary findings indicate that the Coanda effects outside the hole have little effect in drawing three-dimensional jets closer to the wall. Some jets were found ... |
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| Oscillating-Flow Wind Tunnel Studies for a Circulation Control Circular Cylinder |
MAR 91 |
110 pages |
| Authors:
George P. Christopoulos; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| A two-dimensional circulation control (4.25-in. diam. x 24-in. span) model was designed for installation in the Naval Postgraduate School oscillating flow, low speed wind tunnel. An adjustable, tangential blowing slots was included in the design to provide circulation control capability using the Coanda flow effect aft of the spanwise slot. Orifice locations were defined for obtaining surface static pressures which could be subsequently processed to yield sectional lift and drag ... |
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| Use of Navier-Stokes Methods to Predict Circulation Control Airfoil Performance |
MAR 89 |
84 pages |
| Authors:
Steven L. Williams; AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH SCHOOL OF ENGINEERING
|
| The predictive capability of the two-dimensional compressible mass- averaged Navier-Stokes equations was investigated for a typical circulation control air-foil. The governing equations were solved using the implicit approximate factorization algorithm of Beam-Warming with the turbulence model of Baldwin-Lomax. To account for the unique characteristics of circulation control airfoils, an empirical turbulence model correction due to Bradshaw was used. This thesis is unique in that the predictive capability of the computational ... |
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| Lift Distribution on a High Aspect Ratio Circulation Control Wing with Root Lift Cutout |
JUN 85 |
|
| Authors:
R. J. Furey; DAVID W TAYLOR NAVAL SHIP RESEARCH AND DEVELOPMENT CENTER BETHESDA MD AVIATION AND SURFACE EFFECTS DEPT
|
| A computational procedure is developed, based on lifting line theory, which successfully predicts the spanwise lift distribution at moderate blowing momentum coefficient on a high aspect ratio (AR = 18) circulation control wing- body model with several variations in the spanwise lift distribution which validates this procedure. Additional keywords: Coanda surface; Wing body configurations; Mathematical models. (Author) |
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| Modelling Circulation Control by Blowing |
AUG 1984 |
12 pages |
| Authors:
M. M. Soliman; R V. Smith; I. C. Cheeseman; SOUTHAMPTON UNIV (UNITED KINGDOM)
|
| This paper describes a new theoretical representation of circulation control based on discrete vortex modelling techniques. The application of discrete vortex modelling to the prediction of circulation control is initially presented for the Coanda flow of a wall jet around a circular cylinder in a free stream. The decay in the jet momentum, due to viscous and entrainment effects, has been represented in the model by decaying the strength of ... |
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| Leading Edge Augmentor Wing-in-Ground Effect Vehicle. |
17 APR 1984 |
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| Authors:
David G. Rousseau; DEPARTMENT OF THE NAVY WASHINGTON DC
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| A Wing-in-Ground (WIG) effect vehicle for traveling over water utilizing the efflux from propulsors to create a static pressure increase under the wings. The propulsors are carried inside the fuselage or in other safe locations away from sea spray and debris. The efflux is carried by conduit running the full span of the wing leading edge and is directed under the wing. The efflux also entrains ambient air by Coanda ... |
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| An Experimental Study of Thrust Augmenting Ejectors |
DEC 1983 |
59 pages |
| Authors:
W. D. Lewis; AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH SCHOOL OF ENGINEERING
|
| An automated thrust augmentation data acquisition facility was designed and constructed. The facility provides the capability of measuring thrust augmentation ratio and mass flow augmentation ratio. A three dimensional graphics plot of exit flow is provided for flow analysis. Tests were conducted on a 4.4 in. diameter circular ejector, with eight primary nozzles mounted symmetrically along the perimeter of the inlet. A fixed ejector geometry was used. The ratio of ... |
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| Investigation of Parameters Influencing the Deflection of a Thick Wall Jet by a Thin Wall Jet Coflowing over a Rounded Corner |
DEC 1983 |
54 pages |
| Authors:
G. G. Huson; DAVID W TAYLOR NAVAL SHIP RESEARCH AND DEVELOPMENT CENTER BETHESDA MD AVIATION AND SURFACE EFFECTS DEPT
|
| Recent investigations proved the compatibility of the Circulation Control and the Upper Surface Blowing Concepts. This static investigation is a follow-up to determine what combinations of geometric and pneumatic variables produce an effective deflection of a thick wall jet by a thin wall jet exhausting over a rounded corner. Static pressure distributions over the corner indicate that maximum deflections of the thick wall jet occur when a high average suction ... |
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| Reattachment of a Three-Dimensional, Incompressible Jet to an Adjacent Axisymmetric Inclined Surface |
MAR 1983 |
44 pages |
| Authors:
E. E. Niemi Jr; LOWELL UNIV RESEARCH FOUNDATION MA
|
| A study was made of the fluid mechanics of a thrust reverser jet reattaching to an aircraft nozzle afterbody. The problem basically involves the Coanda effect flow of a three-dimensional, incompressible jet to an adjacent axisymmetric, inclined surface. The equations were derived in integral form and programmed for numerical solution for the case of an exhaust flow with no opposing free stream flow. Test data are reported for a scale ... |
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| COANDA Control of a Thick Wall-Jet in the Static Case |
NOV 1982 |
10 pages |
| Authors:
G. G. Hudson; DAVID W TAYLOR NAVAL SHIP RESEARCH AND DEVELOPMENT CENTER ANNAPOLIS MD
|
| The thrust from a turbofan engine top-mounted on a circulation control (CC) wing was recently found to vector downward (and in some cases more than 90 degrees downward, producing thrust reversal) when the CC Coanda jet is activated. Experimental research was undertaken to provide a basis for understanding this phenomenon, for projecting its practical limits, and for exploiting its benefits. Within the range of parameters investigated, thrust- turning performance tended ... |
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| Ground Runup Noise Suppression Program. Part 3. Dry Suppressor Technology Base |
20 JUN 1982 |
|
| Authors:
R. Glass; M. Lepor; NAVAL OCEAN SYSTEMS CENTER SAN DIEGO CA
|
| The Ground Runup Noise Suppression Final Report consists of three documents. The first document, part 1, is an executive summary which provides a brief, technical description and overview of the program conducted at the Naval Ocean Systems Center (NOSC). The second document, Part 2, provides a documented history of NOSC's participation in the Dry Jet Noise Suppression Program. This document, part 3, is a technical summary of the information and ... |
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| An Experimental Study of Rectangular and Circular Thrust Augmenting Ejectors |
DEC 1981 |
74 pages |
| Authors:
Gregory Unnever; AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH SCHOOL OF ENGINEERING
|
| A short rectangular ejector and two circular ejectors were tested to determine the effects of primary nozzle configuration and geometry on thrust augmentation. The primary nozzle configurations consisted primarily of slot nozzles which injected fluid parallel to the diffuser walls and achieved Coanda type flow at the throat. Results of the rectangular ejector tests indicate that thin plates installed in the mixing chamber or the diffuser, increase mixing but decrease ... |
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| A Flight Test Evaluation of the Ball-Bartoe Jetwing Propulsive Lift Concept |
01 JUL 1981 |
189 pages |
| Authors:
Ralph d. Kimberlin; TENNESSEE UNIV SPACE INST TULLAHOMA
|
| The need for military aircraft that will operate from short unimproved airfields, and the decks of smaller aircraft carriers has increased in recent years due to a changing world situation and the shrinking of the dollar. Such aircraft need to be fuel efficient, quiet, maneuverable, have low infrared signature, and carry a large useful load. The Ball-Bartoe 'Jetwing' is a single engine upper surface blowing concept which offers the possibility ... |
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| Investigation of the Circulation Control Wing/Upper Surface Blowing High-Lift System on a Low Aspect Ratio Semispan Model |
MAY 1981 |
|
| Authors:
Michael J. Harris; DAVID W TAYLOR NAVAL SHIP RESEARCH AND DEVELOPMENT CENTER BETHESDA MD AVIATION AND SURFACE EFFECTS DEPT
|
| The results from one in a series of investigations undertaken to develop the Circulation Control Wing/Upper Surface Blowing (CCW/USB) high-lift concept are presented. Included are: isolation of propulsion jet turning, effects of tip devices, and thrust reversing. As evaluated, the concept employs a modified supercritical wing with a 3.6-percent chord circular trailing edge and tangential blowing from a thin, full-span slot over this trailing edge. In addition, turbofans are mounted ... |
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| Investigation of Acoustic Interactions in Jet Thrust Augmenting Ejectors |
05 MAR 1981 |
|
| Authors:
J. R. Campbell; K. D. Korkan; H. Viets; ROCKWELL INTERNATIONAL COLUMBUS OH NORTH AMERICAN AIRCRAFT OPERATIONS
|
| The performance of a constant area rectangular ejector with varying mixing length was investigated to determine the aeroacoustics interaction effects. The rectangular ejector investigation was conducted in two phases. The phase one investigation involved the testing of three different aspect ratio rectangular convergent nozzles at pressure between 15-45 psig to determine the acoustic and jet spreading characteristics. From these data a rectangular ejector incorporating endwall and ejector flap blowing was ... |
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| Design of a Slot Height Distribution for Increased Hover Control Power on a Circulation Control Rotor |
DEC 1980 |
|
| Authors:
Daniel W. Poe; DAVID W TAYLOR NAVAL SHIP RESEARCH AND DEVELOPMENT CENTER BETHESDA MD AVIATION AND SURFACE EFFECTS DEPT
|
| The Circulation Control Rotor Performance Prediction computer program was used with the XH-2/CCR rotor configuration to determine a slot height distribution that would improve control power in hover without causing excessive cyclic pressure requirements for trim in forward flight. Effects of total slot area as well as distribution were considered. The final distribution was constrained by a minimum practical slot height setting of 0.002 in. and a minimum unpressurized blade ... |
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| Computation of the Turbulent Mixing in Curved Ejectors |
30 APR 1980 |
44 pages |
| Authors:
E. F. Schum; P. M. Bevilaqua; S. V. Patankar; ROCKWELL INTERNATIONAL COLUMBUS OH NORTH AMERICAN AIRCRAFT OPERATIONS
|
| A numerical method has been developed to calculate the effects of curvature on the turbulent mixing within a thrust augmenting ejector. Curvature modification are included in both the kinetic energy and dissipation equations of the turbulence model. The elliptic effects of curvature on the mean flow are determined by combining an elliptic solution for the pressure field with a conventional marching solution for the velocity field. Predictions of the velocity ... |
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| JA-6A Circulation Control Wing Contractor Flight Demonstration. |
28 AUG 1979 |
|
| Authors:
R. W. Boyd; NAVAL AIR TEST CENTER PATUXENT RIVER MD
|
| A circulation Control Wing (CCW) Flight Demonstrator was designed and built by Grumman Aerospace Corporation (GAC) using a modified A-6A airplane. The design was a joint effort by David Taylor Naval Ship Research and Development Center (DTNSRDC) and GAC based on research originated by DTNSRDC. The airplane demonstrated significant STOL potential. COmpared to the basic A-6A airplane, takeoff and landing roll distances were improved by 36% and 43%, respectively. Maximum ... |
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| Experimental Investigation of a Circulation Control Aileron. |
JUL 1979 |
|
| Authors:
Steven W. Prince; DAVID W TAYLOR NAVAL SHIP RESEARCH AND DEVELOPMENT CENTER BETHESDA MD AVIATION AND SURFACE EFFECTS DEPT
|
| A Circulation Control (CC) aileron was tested on a semispan wing-fuselage model at a dynamic pressure equal to 20 lb/sq ft (957 N/sq m) and a Reynolds number of 0.8 million per ft (2.62 million per m). Three different trailing edge geometries were used on CC ailerons of 10 and 20 percent of the half span. Blowing was controlled to produce jet momentum coefficients from 0.0017 to 0.0124. Rolling moment ... |
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| The Low-Speed Characteristics of a 15-Percent Quasi-Elliptical Circulation Control Airfoil with Distributed Camber. |
MAY 1979 |
|
| Authors:
Jane Abramson; DAVID W TAYLOR NAVAL SHIP RESEARCH AND DEVELOPMENT CENTER BETHESDA MD AVIATION AND SURFACE EFFECTS DEPT
|
| The aerodynamic characteristics of a circulation control elliptic airfoil section with a 15-percent thickness-to-chord ratio were evaluated subsonically. The airfoil, designated NCCR1513-7559E, incorporates a high degree of nose camber and an increased leading edge radius in a profile designed for high subsonic speeds. Critical Mach numbers in excess of 0.7 were predicted analytically for several typical operating conditions. Lift coefficients up to 4.63 were produced at momentum coefficients of 0.22. ... |
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| Jet Engine Class 'C' Test Cell Exhaust System Phase. Coanda/Refraction Noise Suppression Concept-Advanced Development. |
MAY 1979 |
|
| Authors:
R. E. Ballard ; D. L. Armstrong; BOEING WICHITA CO KS
|
| The successfully demonstrated Coanda/refraction air-cooled exhaust noise suppressor system is applied to the Navy requirement for an effective air-cooled retrofit configuration for the class 'C' test cells (concrete enclosure). The technical approach consists of analytically sizing retrofit components to meet both acoustic ad aerothermodynamic requirements and then testing at one-sixth scale using simulated afterburning engine exhaust to verify the design configuration. Model variations included exhaust stack height, exhaust stack inner ... |
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| Jet Engine Demountable Test Cell Exhaust System Phase - Coanda/Refraction Noise Suppression Concept - Advanced Development. |
APR 1979 |
|
| Authors:
R. E. Ballard ; W. F. Byers ; D. L. Armstrong; BOEING WICHITA CO KS
|
| The successfully demonstrated Coanda/refraction air-cooled exhaust noise suppressor system is applied to the Navy requirement for effective exhaust noise suppression in jet engine demountable test cells. The technical approach consists of analytical studies and one-sixth scale model tests using simulated afterburning engine exhaust. Revisions are made to the previously developed system to improve noise suppression capability while reducing the system overall size and initial cost. Revisions include moving secondary air ... |
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| Development of the A-6/Circulation Control Wing Flight Demonstrator Configuration |
JAN 1979 |
155 pages |
| Authors:
Robert J. Englar; DAVID W TAYLOR NAVAL SHIP RESEARCH AND DEVELOPMENT CENTER BETHESDA MD AVIATION AND SURFACE EFFECTS DEPT
|
| Wind tunnel investigations were conducted on a 1/8.5-scale model of the A-6/Circulation Control Wing (CCW) flight demonstrator aircraft in order to confirm the high lift capability of the concept, to improve lifting and control surfaces and to provide supporting data to assure safety of flight and adequate handling of the full-scale aircraft. The best configuration developed during these investigations produced a 2.2-fold increase in C sub L max over the ... |
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| A Viscous/Potential Flow Interaction Analysis for Circulation-Controlled Airfoils. |
MAY 1978 |
|
| Authors:
F. A. Dvorak; ANALYTICAL METHODS INC BELLEVUE WASH
|
| A method developed for the analysis of the incompressible viscous flow over circulation-controlled airfoils is described. A surface vorticity method is used to solve the inviscid portion of the flow and a combination of integral and finite difference methods is used to calculate the development of the viscous layers. An iterative process is used to arrive at final solutions which satisfy an appropriate trailing-edge condition and incorporate the interaction between ... |
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| An Analysis of the Stability of an Aircraft Equipped with an Air Cushion Recovery System. |
MAR 1978 |
|
| Authors:
Max Allen Stafford; AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OHIO SCHOOL OF ENGINEERING
|
| The stability of an aircraft equipped with an air cushion recovery system (ACRS) was investigated both in-flight and during the landing (slideout) phase of flight. Digital computer simulations were used to identify unstable tendencies of a specific aircraft (the Jindivik drone). Control system designs are proposed to eliminate the instabilities. A nonlinear, six degree of freedom, aerodynamic model is developed based on available wind-tunnel data. The model is used in ... |
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| Viscid/Inviscid Interaction Analysis of Thrust Augmenting Ejectors. |
28 FEB 1978 |
|
| Authors:
P. M. Bevilaqua; A. D. DeJoode; ROCKWELL INTERNATIONAL COLUMBUS OHIO COLUMBUS AIRCRAFT DIV
|
| A method has been developed for calculating the static performance of thrust augmenting ejectors by matching a viscous solution for the flow through the ejector to an inviscid solution for the flow outside the ejector. In effect, the ejector shroud is considered to be 'flying' in the secondary velocity field induced by the entrainment of the primary jets. A two-dimensional analysis utilizing a turbulence kinetic energy model for the inner, ... |
|
| Jet Engine Tail Pipe Flow Deflector. |
24 JAN 1978 |
|
| Authors:
John C. Vaughan III; DEPARTMENT OF THE AIR FORCE WASHINGTON D C
|
| Apparatus for producing a component of thrust at right angles to the main thrust direction of a jet engine. The apparatus comprises a deflecting device which provides a surface, bounded by side walls normal to the surface, that curves outwardly from tangency to the main thrust direction at the tail pipe edge. A series of control ports extending transversely of the curved surface at the point of tangency are connected ... |
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| A Computational Model for Three-Dimensional Incompressible Small Cross Flow Wall Jets. |
15 DEC 1977 |
|
| Authors:
Norman D. Malmuth; R. K. Szeto; ROCKWELL INTERNATIONAL THOUSAND OAKS CALIF SCIENCE CENTER
|
| A computational model based on H. Keller's box scheme has been used to characterize turbulent incompressible wall jets in the small cross flow approximation prototypic of flows over upper-surface-blown and augmenter wings. Submerged and coflowing cases are considered. An eddy viscosity model was used to simulate the effects of turbulence. Approximate models are identified for flows in which the jet height tends to zero. If the span flow is introduced ... |
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| Circulation Control Airfoil Study. |
21 NOV 1977 |
|
| Authors:
Louis V. Schmidt; NAVAL POSTGRADUATE SCHOOL MONTEREY CALIF
|
| The prime goal of the investigations has been the evaluation of the unsteady aerodynamics, and in particular the transfer functions, applicable to the Circulation Control Airfoil (CCA) for the situation of harmonic blowing perturbations superimposed upon a mean cavity pressure. Circulation control was achieved upon the relatively thick (t/c = 0.214) elliptically shaped two-dimensional air foil by tangential jet injection at an upper surface slot just ahead of the rounded ... |
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| Two-Dimensional Subsonic Wind Tunnel Evaluation of Two Related Cambered 15-Percent Thick Circulation Control Airfoils |
SEP 1977 |
68 pages |
| Authors:
Jane Abramson; DAVID W TAYLOR NAVAL SHIP RESEARCH AND DEVELOPMENT CENTER BETHESDA MD AVIATION AND SURFACE EFFECTS DEPT
|
| Two circulation control cambered elliptic airfoil sections with a thickness-to-chord ratio of 0.15- and 1.0-percent circular arc camber were evaluated subsonically to determine their aerodynamic characteristics. The two models, designated NCCR 1510-7067N and NCCR 1510-7567S, have a common leading edge but different Coanda surfaces. |
|
| An Investigation of the Performance of a J52-P-8A Engine Operating under the Influence of High Bleed Flow Extraction Rates. |
AUG 1977 |
|
| Authors:
Rodney A. Hemmerly; DAVID W TAYLOR NAVAL SHIP RESEARCH AND DEVELOPMENT CENTER BETHESDA MD AVIATION AND SURFACE EFFECTS DEPT
|
| The uninstalled performance characteristics of a J52-P-8A engine operating under the influence of bleed flow extraction rates in excess of the standard specification limits were experimentally evaluated. This investigation was undertaken as part of the Circulation Control Wing Flight Demonstrator Program to assess engine capability of supplying airflow to power the high-lift aerodynamic system incorporated on the Flight Demonstrator and define a data base from which higher confidence level analytical ... |
|
| A Circulation Controlled Rotor Blade. |
24 JUN 1977 |
|
| Authors:
J. Schmidt; DEPARTMENT OF THE NAVY WASHINGTON D C
|
| A circulation controlled rotor blade is described which reduces rotor flutter by introducing a laminar flow over the trailing edge. A trailing edge structure has a deformable tube to control a spanwise slot formed by the juxtaposition of an upper trailing edge lip over the deformable tube. The laminar flow is created by compressed fluid directed through the rotor blade and through the slot. |
|
| Static Evaluation of a Circulation Control Centrifugal Fan. |
JUN 1977 |
|
| Authors:
Roger J. Furey; Robert E. Whitehead; DAVID W TAYLOR NAVAL SHIP RESEARCH AND DEVELOPMENT CENTER BETHESDA MD
|
| The static characteristics of a circulation control (CC) fan were determined to demonstrate the feasibility of the CC concept as a means of meeting the lift system requirements of a large, open ocean capable, surface effect ship (SES). These requirements being variable performance, at constant RPM, of sufficient range to provide for heave alleviation when operating at high speeds in advanced sea-states. The scope of the program included two solidity ... |
|
| Hover Evaluation of the Circulation Control High Speed Rotor. |
JUN 1977 |
|
| Authors:
Kenneth R. Reader; DAVID W TAYLOR NAVAL SHIP RESEARCH AND DEVELOPMENT CENTER BETHESDA MD AVIATION AND SURFACE EFFECTS DEPT
|
| A high-speed rotor model, designated the RB-CCR (reverse blowing circulation control rotor), was evaluated in the hover mode. The model was tested as two- and four-bladed rotor with several rotor configurations. In general the hover tests demonstrated that a good figure of merit can be obtained over a large range of collective pitch angles. A comparison of configurations at various collective angles showed a steady improvement in performance with increasing ... |
|
| Data Reduction for the Unsteady Aerodynamics on a Circulation Control Airfoil. |
MAR 1977 |
|
| Authors:
Billy Murel Pickelsimer; NAVAL POSTGRADUATE SCHOOL MONTEREY CALIF
|
| Calculating the lift, drag, and pitching moment coefficients for an airfoil from the static pressure distribution obtained from wind tunnel tests is routine task when steady flow is considered, but it is much more complicated when the airfoil is operating in an unsteady flow field, similar to that experienced by a helicopter rotor blade, produced by an oscillating wind tunnel. A data reduction routine capable of condensing the large numbers ... |
|
| Design and Fabrication of Coanda Suppressor Flow Visualization Model |
10 FEB 1977 |
|
| Authors:
Dale W. Brees; BOEING CO SEATTLE WA
|
| Because the Navy Coanda noise suppressor exhibited three-dimensional flow anomalies a 1/2oth scale transparent laboratory model was fabricated to provide for visualization of the internal flow. Identification of flow anomalies and methods of correcting them by geometric design changes thus eliminating local acoustic lining erosion was the primary purpose for the model. In addition, model experimental flow data were to be correlated to analytical computer codings so they could be ... |
|
| Fluidic Angle-of-Attack Sensor. |
07 SEP 1976 |
|
| Authors:
Perer A. Freeman; DEPARTMENT OF THE NAVY WASHINGTON D C
|
| The patent relates to a fluidic angle-of-attack sensor for providing a differential output proportional to the angle-of-attack of flow impinging on the sensor. An excitation flow nozzle discharges into a coanda-effect cavity which opens into a centrally oriented impingement cavity so that excitation flow penetrates and impinges on the ambient flow field. A pair of output ports alternately intercept part of the excitation stream to provide a differential output pressure. ... |
|
| AN Analytical Study of a Boundary Layer TVC Nozzle Concept. |
MAR 1976 |
|
| Authors:
H. H. Tang; W. A. Anderson; J. Xerikos; MCDONNELL DOUGLAS ASTRONAUTICS CO HUNTINGTON BEACH CA
|
| Experimental investigations of the feasibility of directing missile thrust by controlling ambient airflow through ports in overexpanded nozzles have been conducted by the Naval Weapons Center and an NWC-sponsored contractor. Chandler Evans, Inc. The present analytical effort studied boundary-layer thrust vector control (BLTVC) technology with the following specific objectives: (1) Development of analytical or semi-empirical descriptions of the dominant phenomena that characterize the BLTVC flow field; (2) Derivation of similarity ... |
|
| An Experimental Investigation of the Whistler Nozzle and an Analytical Investigation of a Ring Wing in Supersonic Flow |
MAR 1976 |
|
| Authors:
Donald L. Weiss; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| This thesis consists of two parts. First, an experimental investigation of a new device called the whistler nozzle was conducted. Experiments were conducted in the areas of nozzle efficiency, mass entrainment, and flow visualization. Flow visualization showed the presence of a Coanda type jet wall interaction in the nozzle collar. Thrust efficiencies indicated that whistling could be achieved without much greater losses than the basic axisymmetric jet. Entrainment tests were ... |
|
| Fluidics Technology. |
JAN 1976 |
|
| Authors:
J. M. Kirshner; ADVISORY GROUP FOR AEROSPACE RESEARCH AND DEVELOPMENT PARIS (FRANCE)
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| This AGARDograph is based on material presented at a symposium on fluidics held by the Harry Diamond Laboratories of the United States Army. It largely represents a selection of material from the proceedings of this symposium, edited in the interests of a wider audience. The object of the compilation is to overview in concise form the present state of research, technology and applications of fluidics. An opening section on sensors ... |
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