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A Method of Computing the Transient Temperature of Thick Walls From Arbitrary Variation of Adiabatic-Wall Temperature and Heat-Transfer Coefficient

Description: "A method of calculating the temperature of thick walls has been developed in which the time series and the response to a unit triangle variation of surface temperature concepts are used, together with essentially standard formulas for transient temperature and heat flow into thick walls. The method can be used without knowledge of the mathematical tools of its development. The method is particularly suitable for determining the wall temperature in one-dimensional thermal problems in aeronautic… more
Date: June 18, 1957
Creator: Hill, P. R.
Item Type: Refine your search to only Report
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Calculated and Measured Stresses in Simple Panels Subject to Intense Random Acoustic Loading Including the Near Noise Field of a Turbojet Engine

Description: "Flat 2024-T3 aluminum panels measuring 11 inches by 13 inches were tested in the near noise fields of a 4-inch air jet and turbojet engine. The stresses which were developed in the panels are compared with those calculated by generalized harmonic analysis. The calculated and measured stresses were found to be in good agreement. In order to make the stress calculations, supplementary data relating to the transfer characteristics, damping, and static response of flat and curved panels under peri… more
Date: June 3, 1957
Creator: Lassiter, Leslie W. & Hess, Robert W.
Item Type: Refine your search to only Report
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Spark ignition of flowing gases

Description: Research conducted at the NACA Lewis Laboratory on ignition of flowing gases by means of long-duration discharges is summarized and analyzed. Data showing the effect of a flowing combustible mixture on the physical and electrical characteristics of spark discharges and data showing the effects of variables on the spark energy required for ignition that has been developed to predict the effect of many of the gas-stream and spark variables is described and applied to a limited amount of experimen… more
Date: June 20, 1956
Creator: Swett, Clyde C., Jr.
Item Type: Refine your search to only Report
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Torsional Stiffness of Thin-Walled Shells Having Reinforcing Cores and Rectangular, Triangular, or Diamond Cross Section

Description: "A theoretical investigation has been made of the Saint-Venant torsion of certain composite bars. These bars are composed of two materials -- one material in the form of a thin-walled cylindrical shell and the other material in the form of a core which fills the interior of the shell and is bonded to it. An approximate boundary-value problem is formulated on assumptions similar to those of the theory of torsion of hollow thin-walled shells (Bredt theory)" (p. 771).
Date: June 7, 1956
Creator: McComb, Harvey G., Jr.
Item Type: Refine your search to only Report
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An experimental investigation of sting-support effects on drag and a comparison with jet effects at transonic speeds

Description: Various dummy stings were tested on the rear of a related series of afterbody shapes for Mach numbers from 0.80 to 1.10 and Reynolds numbers based on body length from 15.0 x 16 to the 6th power to 17.4 x 10 to the 6th power. A method is presented whereby approximate sting interference corrections can be made to models having afterbody shapes and sting supports similar to those of these tests if the Reynolds numbers are of the same order of magnitude and a turbulent boundary layer exists at the … more
Date: June 4, 1956
Creator: Cahn, Maurice S.
Item Type: Refine your search to only Report
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Influence of Alloying upon Grain-Boundary Creep

Description: "Grain-boundary displacement, occurring in bicrystals during creep at elevated temperature (350 degrees c), has been measured as a function of the copper content (0.1 to 3 percent) in a series of aluminum-rich aluminum-copper solid-solution alloys. The minimums in stress and temperature, below which grain-boundary motion does not occur, increase regularly with the copper content as would be expected if recovery is necessary for movement. Otherwise, the effects, if any, of the copper solute upon… more
Date: June 24, 1955
Creator: Rhines, F. N.; Bond, W. E. & Kissel, M. A.
Item Type: Refine your search to only Report
open access

NACA Transonic Wind-Tunnel Test Sections

Description: Report presents an approximate subsonic theory for the solid-blockage interference in circular wind tunnels with walls slotted in the direction of flow. This theory indicated the possibility of obtaining zero blockage interference. Tests in a circular slotted tunnel based on the theory confirmed the theoretical predictions.
Date: June 20, 1955
Creator: Wright, Ray H. & Ward, Vernon G.
Item Type: Refine your search to only Report
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On boattail bodies of revolution having minimum wave drag

Description: The problem of determining the shape of slender boattail bodies of revolution for minimum wave drag has been reexamined. It was found that minimum solutions for Ward's slender-body drag equation can exist only for the restricted class of bodies for which the rate of change of cross-sectional area at the base is zero. In order to eliminate this restriction, certain higher order terms must be retained in the drag equation and isoperimetric relations. The minimum problem for the isoperimetric cond… more
Date: June 8, 1955
Creator: Harder, Keith C. & Rennemann, Conrad, Jr.
Item Type: Refine your search to only Report
open access

Incompressible Flutter Characteristics of Representative Aircraft Wings

Description: "This report gives the results of a detailed study of the flutter characteristics of four representative aircraft wings. This study was made using the electric-analog computer at the California Institute of Technology. During the course of this investigation eight important parameters of each wing were varied and, in addition, the effects of mass, inertia, pitching spring, and location of a concentrated mass were investigated for all four wings and at several sweepback angles" (p. 1385).
Date: June 6, 1955
Creator: Wilts, C. H.
Item Type: Refine your search to only Report
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Comparison of performance of experimental and conventional cage designs and materials for 75-millimeter-bore cylindrical roller bearings at high speed

Description: From Summary: "The results of two investigations, one to determine the relative merits of four experimental and two conventional design 75-millimeter-bore (size 215) cylindrical roller bearings and one to determine the relative merits of nodular iron and bronze as cage materials for this size and type of bearing, are presented in this report. Nine test bearings were operated over a range of dn values (product of bearing bore in mm and shaft speed in r.p.m) from 0.3 x 10(6) to 2.3 x 20(6), radia… more
Date: June 30, 1954
Creator: Anderson, William J.; Macks, E. Fred & Nemeth, Zolton N.
Item Type: Refine your search to only Report
open access

Generalized Indical Forces on Deforming Rectangular Wings in Supersonic Flight

Description: "A method is presented for determining the time-dependent flow over a rectangular wing moving with a supersonic forward speed and undergoing small vertical distortions expressible as polynomials involving spanwise and chordwise distances. The solution for the velocity potential is presented in a form analogous to that for steady supersonic flow having the familiar "reflected area" concept discovered by Evvard. Particular attention is paid to indicial-type motions and results are expressed in te… more
Date: June 30, 1954
Creator: Lomax, Harvard; Fuller, Franklyn B. & Sluder, Loma
Item Type: Refine your search to only Report
open access

Shock-turbulence interaction and the generation of noise

Description: Interaction of convected field of turbulence with shock wave is analyzed to yield modified turbulence, entropy spottiness, and noise generated downstream of the shock. Analysis is generalization of single-spectrum-wave treatment of NACA-TN-2864. Formulas for spectra and correlations are obtained. Numerical calculations yield curves of rms velocity components, temperature, pressure, and noise in db against Mach number for m = 1 to infinity; both isotropic and strongly axisymmetric (lateral/longi… more
Date: June 3, 1954
Creator: Ribner, H. S.
Item Type: Refine your search to only Report
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Cooperative Investigation of Relationship Between Static and Fatigue Properties of Wrought N-155 Alloy at Elevated Temperatures

Description: Report presents the correlation of extensive data obtained relating properties of wrought N-155 alloy under static, combined static and dynamic, and complete reversed dynamic stress conditions. Time period for fracture ranged from 50 to 500 hours at room temperature, 1,000 degrees, 1,200 degrees, and 1,500 degrees F.
Date: June 15, 1953
Creator: NACA Subcommittee on Power-Plant Materials
Item Type: Refine your search to only Report
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Analytical Derivation and Experimental Evaluation of Short-Bearing Approximation for Full Journal Bearing

Description: From Introduction: "This report extends the short-bearing pressure-distribution function of Michell and Cardullo to give equations for the various bearing characteristics. This short-bearing approximation makes available formulas relating eccentricity ratio to applied load, attitude angle, angular position of peak film pressure to unit pressure on projected area."
Date: June 12, 1953
Creator: DuBois, George B. & Ocvirk, Fred W.
Item Type: Refine your search to only Report
open access

Studies of the speed stability of a tandem helicopter in forward flight

Description: Flight-test measurements, related analytical studies, and corresponding pilots' opinions of the speed stability of tandem-rotor helicopter are presented. An undesirable instability, evidenced by rearward stick motion with increasing forward speed at constant power, is indicated to be caused by variations with speed of the front-rotor downwash at the rear rotor. An analytical expression for predicting changes in speed stability caused by changes in rotor geometry is derived and constants for use… more
Date: June 4, 1953
Creator: Tapscott, Robert J. & Amer, Kenneth B.
Item Type: Refine your search to only Report
open access

High-Resolution Autoradiography

Description: This investigation was made to adapt wet-process autoradiography to metallurgical samples to obtain high resolution of segregated radioactive elements in microstructures. Results are confined to development of the technique, which was perfected to a resolution of less than 10 microns. The radioactive samples included carbon-14 carburized iron and steel, nickel-63 electroplated samples, a powder product containing nickel-63, and tungsten-185 in N-155 alloy.
Date: June 1, 1953
Creator: Towe, George C.; Gomberg, Henry J. & Freemen, J. W.
Item Type: Refine your search to only Report
open access

Experimental investigation of free-convection heat transfer in vertical tube at large Grashof numbers

Description: Report presents the results of an investigation conducted to study free-convection heat transfer in a stationary vertical tube closed at the bottom. The walls of the tube were heated, and heated air in the tube was continuously replaced by fresh cool air at the top. The tube was designed to provide a gravitational field with Grashof numbers of a magnitude comparable with those generated by the centrifugal field in rotating-blade coolant passages (10(8) to 10(13)). Local heat-transfer coefficien… more
Date: June 30, 1952
Creator: Eckert, E. R. G. & Diaguila, A. J.
Item Type: Refine your search to only Report
open access

Theory and Procedure for Determining Loads and Motions in Chine-Immersed Hydrodynamic Impacts of Prismatic Bodies

Description: "A theoretical method is derived for the determination of the motions and loads during chine-immersed water landings of prismatic bodies. This method makes use of a variation of two-dimensional deflected water mass over the complete range of immersion, modified by a correction for three-dimensional flow. Equations are simplified through omission of the term proportional to the acceleration of the deflected mass for use in calculation of loads on hulls having moderate and heavy beam loading" (p.… more
Date: June 25, 1952
Creator: Schnitzer, Emanuel
Item Type: Refine your search to only Report
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The effects on dynamic lateral stability and control of large artificial variations in the rotary stability derivatives

Description: This report presents the results of an investigation conducted in the Langley free-flight tunnel to determine the effects of large artificial variations of several rotary lateral-stability derivatives on the dynamic lateral stability and control characteristics of a 45 degree sweptback-wing airplane model. Calculations of the period and damping of the lateral motions and of the response to roll and yaw disturbances were made for correlation with the experimental results. The calculated results … more
Date: June 20, 1952
Creator: Schade, Robert O. & Hassell, James L., Jr.
Item Type: Refine your search to only Report
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A summary of lateral-stability derivatives calculated for wing plan forms in supersonic flow

Description: "A compilation of theoretical values of the lateral-stability derivatives for wings at supersonic speeds is presented in the form of design charts. The wing plan forms for which this compilation has been prepared include a rectangular, two trapezoidal, two triangular, a fully-tapered swept-back, a sweptback hexagonal, an unswept hexagonal, and a notched triangular plan form. A full set of results, that is, values for all nine of the lateral-stability derivatives for wings, was available for the… more
Date: June 26, 1951
Creator: Jones, Arthur L. & Alksne, Alberta
Item Type: Refine your search to only Report
open access

Calculations of Laminar Heat Transfer Around Cylinders of Arbitrary Cross Section and Transpiration-Cooled Walls With Application to Turbine Blade Cooling

Description: "An approximate method for the development of flow and thermal boundary layers in the laminar region on cylinders with arbitrary cross section and transpiration-cooled walls is obtained by the use of Karman's integrated momentum equation and an analogous heat-flow equation. Incompressible flow with constant property values throughout the boundary layer is assumed. The velocity and temperature profiles within the boundary layer are approximated by expressions composed of trigonometric functions"… more
Date: June 22, 1951
Creator: Eckert, E. R. G. & Livingood, J. N. B.
Item Type: Refine your search to only Report
open access

Air forces and moments on triangular and related wings with subsonic leading edges oscillating in supersonic potential flow

Description: From Introduction: "This report is concerned with the derivation of expressions for the velocity potential and associated forces and moments for oscillating triangular wings in supersonic flow. The purpose of the present report is to make use of the expanded form of the velocity potential to obtain the forces and moments, based on the first terms of this potential, for a rigid triangular wing performing vertical and pitching sinusoidal oscillations in mixed supersonic flow."
Date: June 19, 1951
Creator: Watkins, Charles E. & Berman, Julian H.
Item Type: Refine your search to only Report
open access

Discussion of boundary-layer characteristics near the wall of an axial-flow compressor

Description: From Summary: "The boundary-layer velocity profiles in the tip region of an axial-flow compressor downstream of the guide vanes and downstream of the rotor were measured by use of total-pressure and claw-type yaw probes. These velocities were resolved into two components: one along the streamline of the flow outside the boundary layer, and the other perpendicular to it. The affinity among all profiles was thus demonstrated with the boundary-layer thickness and the deflection of the boundary lay… more
Date: June 7, 1951
Creator: Mager, Artur; Mahoney, John J. & Budinger, Ray E.
Item Type: Refine your search to only Report
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