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The Supersonic Axial-Flow Compressor

Description: An investigation has been made to explore the possibilities of axial-flow compressors operating with supersonic velocities into the blade rows. Preliminary calculations showed that very high pressure ratios across a stage, together with somewhat increased mass flows, were apparently possible with compressors which decelerated air through the speed of sound in their blading. The first phase of the investigation was the development of efficient supersonic diffusers to decelerate air through the speed of sound. The present report is largely a general discussion of some of the essential aerodynamics of single-stage supersonic axial-flow compressors. As an approach to the study of supersonic compressors, three possible velocity diagrams are discussed briefly. Because of the encouraging results of this study, an experimental single-stage supersonic compressor has been constructed and tested in Freon-12. In this compressor, air decelerates through the speed of sound in the rotor blading and enters the stators at subsonic speeds. A pressure ratio of about 1.8 at an efficiency of about 80 percent has been obtained.
Date: January 1, 1950
Creator: Kantrowitz, Arthur
Partner: UNT Libraries Government Documents Department

Paths of Target Seeking Missiles in Two Dimensions

Description: Parameters that enter into equation of trajectory of a missile are discussed. Investigation is made of normal pursuit, of constant, proportional, and line--of-sight methods of navigation employing target seeker, and of deriving corresponding pursuit paths. Pursuit paths obtained under similar conditions for different methods are compared. Proportional navigation is concluded to be best method for using target seeker installed in missile.
Date: July 1946
Creator: Watkins, Charles E.
Partner: UNT Libraries Government Documents Department

Paths of target-seeking missiles in two dimensions

Description: Report presenting a discussion of some of the parameters that enter into the equation of the path of a missile which is pursuing its target. The missile is assumed to be guided by a target seeker that might be employed in any one of several ways. Results regarding the normal-pursuit navigation, constant navigation, proportional navigation, line-of-sight navigation, and effect of angle of attack and sideslip are provided.
Date: July 1946
Creator: Watkins, Charles E.
Partner: UNT Libraries Government Documents Department

Parameters determining performance of supersonic pilotless airplanes powered by ram-compression power planes

Description: Report presenting the dimensional parameters of ram-compression power plants as related to their thrust and economy performance and an investigation of the speed and range performance possibilities of a family of pilotless airplanes powered with one of the power plants. The analysis of the power plants includes the power-plant configuration, aerodynamic and thermodynamic cycle, constants used in the computations, power-plant performance, and operation of the power unit with fixed areas at various flight speeds. The investigation of the aircraft included a description of its characteristics, speed, range, effect of wing selection of speed, and effect of size on performance.
Date: June 1946
Creator: Hill, Paul R.
Partner: UNT Libraries Government Documents Department

Investigations on Laminar Boundary-Layer Stability and Transition on Curved Boundaries

Description: Report presenting an investigation of the transition of the boundary layer from the laminar to the turbulent region on a flat plate, on the concave and convex side of a plate with a 20-foot radius of curvature, and on the convex side of a plate with a 30-inch radius of curvature.
Date: May 1946
Creator: Liepmann, Hans W.
Partner: UNT Libraries Government Documents Department

Stability and Control Force Tests of Four- and Six-Unit Wing Designs of Low Aspect Ratio and 20 Degree Triangular Plan Form

Description: Report presenting an investigation to obtain force-test data on a wing design suitable for high-speed guided missiles, especially data on rolling moments produced in yawed and pitched attitudes. Force tests were conducted on two models of a wing design of low aspect ratio and 20 degree triangular plan form. Results regarding the application of results, four-unit wing design, and six-unit wing design are provided.
Date: May 1946
Creator: Paulson, John W.; Varney, Elizabeth P. & Johnson, Joseph L.
Partner: UNT Libraries Government Documents Department

Critical Mach Numbers of Thin Airfoil Sections with Plain Flaps

Description: Critical Mach number as function of lift coefficient is determined for certain moderately thick NACA low-drag airfoils. Results, given graphically, included calculations on same airfoil sections with plain flaps for small flap deflections. Curves indicate optimum critical conditions for airfoils with flaps in such form that they can be compared with corresponding results for zero flap deflections. Plain flaps increase life-coefficient range for which critical Mach number is in region of high values characteristic of low-drag airfoils.
Date: April 1946
Creator: Pardee, Otway O'M. & Heaslet, Max A.
Partner: UNT Libraries Government Documents Department

Field of Flow About a Jet and Effect of Jets on Stability of Jet-Propelled Airplanes

Description: A theoretical investigation was conducted on jet-induced flow deviation. Analysis is given of flow inclination induced outside cold and hot jets and jet deflection caused by angle of attack. Applications to computation of effects of jet on longitudinal stability and trim are explained. Effect of jet temperature on flow inclination was found small when thrust coefficient is used as criterion for similitude. The average jet-induced downwash over tail plane was obtained geometrically.
Date: April 1946
Creator: Ribner, Herbert S.
Partner: UNT Libraries Government Documents Department

Development of Wing Inlets

Description: Lift, drag, internal flow, and pressure distribution measurements were made on a low-drag airfoil incorporating various air inlet designs. Two leading-edge air inlets are developed which feature higher lift coefficients and critical Mach than the basic airfoil. Higher lift coefficients and critical speeds are obtained for leading half of these inlet sections but because of high suction pressures near exist, slightly lower critical speeds are obtained for the entire inlet section than the basic airfoil.
Date: March 1946
Creator: Racisz, Stanley F.
Partner: UNT Libraries Government Documents Department

Flight Investigation at High Speeds of Profile Drag of Wing of a P-47D Airplane Having Production Surfaces Covered with Camouflage Paint

Description: Wing section outboard of flap was tested by wake surveys in Mach range of 0.25 - 0.78 and lift coefficient range 0.06 - 0.69. Results indicated that minimum profile-drag coefficient of 0.0097 was attained for lift coefficients from 0.16 to 0.25 at Mach less than 0.67. Below Mach number at which compressibility shock occurred, variations in Mach of 0.2 had negligible effect on profile drag coefficient. Shock was not evident until critical Mach was exceeded by 0.025.
Date: March 1946
Creator: Zalovcik, John A. & Daum, Fred L.
Partner: UNT Libraries Government Documents Department

Flight Investigation at High Speeds of Profile Drag of Wing of a P-47d Airplane Having Production Surfaces Covered With Camouflage Paint

Description: Report presenting a flight investigation made at high speeds to determine the profile drag of a P-47D airplane wing with production surfaces covered with camouflage paint. The results indicated that a minimum profile-drag coefficient of 0.0097 was attained for lift coefficients from 0.16 to 0.25 at Mach numbers less than 0.67.
Date: March 1946
Creator: Zalovcik, John A. & Daum, Fred L.
Partner: UNT Libraries Government Documents Department

A method for the calculation of external lift, moment, and pressure drag of slender open-nose bodies of revolution at supersonic speeds

Description: Report presenting a method for the calculation of the external lift, moment, and pressure drag of slender open-nose bodies of revolution at supersonic speeds. The lift, moment, and pressure drag of a typical ramjet body shape are calculated at several Mach numbers. Results regarding the results of the calculations, comparison with experiment, and another application of the method are provided.
Date: March 1946
Creator: Parker, Hermon M.
Partner: UNT Libraries Government Documents Department

Theory and Application of Hot-Wire Instruments in the Investigation of Turbulent Boundary Layers

Description: Report presenting an account of the recent developments in hot-wire instruments for use in turbulent boundary layers to determine the magnitude of the several components of the turbulent velocity fluctuations together with the correlation between them and turbulent shearing stress.
Date: March 1946
Creator: Schubauer, G. B. & Klebanoff, P. S.
Partner: UNT Libraries Government Documents Department

Effects of Specific Types of Surface Roughness on Boundary-Layer Transition

Description: Report presenting tests conducted with two typical low-drag airfoils of 90-inch chord to determine the effects of surface projections, grooves, and sanding scratches on boundary-layer transition. Data were obtained for projections of various sizes and chordwise locations on both low-drag airfoils.
Date: February 1946
Creator: Loftin, Laurence K., Jr.
Partner: UNT Libraries Government Documents Department

Effects of Specific Types of Surface Roughness on Boundary-Layer Transition

Description: Report presenting tests of two typical low-drag airfoils of 90-inch chord to determine the effects of surface projections, grooves, and sanding scratches on boundary-layer transition. Data were obtained for projections of various sizes and chordwise locations on both low-drag airfoils.
Date: February 1946
Creator: Loftin, Laurence K., Jr.
Partner: UNT Libraries Government Documents Department

Effect of Compressibility on the Pressure and Forces Acting on a Modified NACA 65,3-019 Airfoil Having a 0.20-Chord Flap

Description: An investigation has been conducted in the Langley rectangular high-speed tunnel to determine the effect of compressibility on the pressure distribution for a modified NACA 65,3-019 airfoil having a 0.20-chord flap. The investigation was made for an angle-of-attack range extending from -2 to 12 deg at .20 flap deflections from 0 to -12 deg. Test data were obtained for Mach numbers from 0.28 to approximately 0.74. The results show that the effectiveness of the trailing-edge-type control surface rapidly decreased and approached zero as the Mach number increased above the critical value.
Date: January 1, 1946
Creator: Lindsey, W. F.
Partner: UNT Libraries Government Documents Department

Wind-tunnel investigation of an NACA 66-series 16-percent-thick low-drag tapered wing with Fowler and split flaps

Description: Report presenting testing to determine the aerodynamic characteristics of an NACA 66-series 16-percent-thick low-drag tapered wing with Fowler and split flaps. The wing had a straight trialing edge and a constant-chord center section. Results regarding lift and pitching-moment characteristics and stalling characteristics are provided.
Date: January 1946
Creator: Heely, Robert H. & Foster, Gerald V.
Partner: UNT Libraries Government Documents Department

A flight investigation of NACA aileron modifications for the improvement of the lateral control characteristics of a high-speed fighter airplane

Description: Report presenting a flight investigation to improve the lateral control of a high-speed fighter airplane. Testing occurred with the original ailerons and a set of modified ailerons, which consisted of an increased balance chord and increased nose radius. The modified ailerons appear to offer a solution to the problem of aileron overbalance and oscillation in high-speed dives.
Date: December 1945
Creator: Williams, Walter C.
Partner: UNT Libraries Government Documents Department

Two-dimensional wind-tunnel investigation of 0.20-airfoil-chord plain ailerons of different contour on an NACA 65(sub 1)-210 airfoil section

Description: Report presenting an investigation of three interchangeable sealed-gap 0.20-airfoil-chord plain ailerons of different contour on the NACA 65(sub 1)-210 airfoil section. The three aileron contours tested were the true airfoil contour, straight sides, and a beveled trailing edge. Results regarding the aileron effectiveness, aileron hinge moments, lift, pitching moment, and drag are provided.
Date: December 1945
Creator: Underwood, William J.; Braslow, Albert L. & Cahill, Jones F.
Partner: UNT Libraries Government Documents Department

Effects of Compressibility on the Maximum Lift Characteristics and Spanwise Load Distribution of a 12-Foot-Span Fighter-Type Wing of NACA 230-Series Airfoil Sections

Description: Lift characteristics and pressure distribution for a NACA 230 wing were investigated for an angle of attack range of from -10 to +24 degrees and Mach range of from 0.2 to 0.7. Maximum lift coefficient increased up to a Mach number of 0.3, decreased rapidly to a Mach number of 0.55, and then decreased moderately. At high speeds, maximum lift coefficient was reached at from 10 to 12 degrees beyond the stalling angle. In high-speed stalls, resultant load underwent a moderate shift outward.
Date: November 1, 1945
Creator: West, F E
Partner: UNT Libraries Government Documents Department

An Infrared Cloud Indicator 1: Analysis of Infrared-Radiation Exchange With Tables and Chart for Calibration of the Cloud Indicator

Description: Report presenting a description of an experimental model of a flight instrument that utilizes infrared radiations for detecting and indicating the location of clouds at night. A preliminary investigation is made of data in the scientific literature. A table and chart are developed that make it practical to determine the magnitude of the net exchange of radiation for any particular atmosphere of known composition and distribution of temperature.
Date: November 1945
Creator: Warfield, Calvin N. & Kenimer, Robert L.
Partner: UNT Libraries Government Documents Department