National Advisory Committee for Aeronautics (NACA) - 136 Matching Results

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Application of the Method of Coordinate Perturbation to Unsteady Duct Flow

Description: The method of coordinate perturbation is applied to the unsteady flow of a compressible fluid in ducts of variable cross section. Solutions, in the form of perturbation series, are obtained for unsteady flows in ducts for which the logarithmic derivative of area variation with respect to the space coordinate is a function of the 'smallness' parameter of the perturbation series. This technique is applied to the problem of the interaction of a disturbance and a shock wave in a diffuser flow. It i… more
Date: September 1958
Creator: Himmel, Seymour C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Effect of Free-Stream Turbulence on Heat Transfer From a Flat Plate

Description: Turbulence was generated by using screens, and the turbulence percentage was measured by a hot-wire anemometer both in the boundary layer and the free stream. The local heat-transfer coefficient was measured at 12 locations along the plate for the cases of various turbulence levels. The transition Reynolds number from laminar to turbulent flow decreases as the main-stream turbulence level increases. In the range of laminar heat transfer the effect of turbulence in the main flow was not great, b… more
Date: September 1958
Creator: Sugawara, Sugao; Sato, Takashi; Komatsu, Hiroyasu & Osaka, Hiroichi
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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On Possible Similarity Solutions for Three-Dimensional Incompressible Laminar Boundary-Layer Flows Over Developable Surfaces and with Proportional Mainstream Velocity Components

Description: Analysis is presented on the possible similarity solutions of the three-dimensional, laminar, incompressible, boundary-layer equations referred to orthogonal, curvilinear coordinate systems. Requirements of the existence of similarity solutions are obtained for the following: flow over developable surface and flow over non-developable surfaces with proportional mainstream velocity components.
Date: September 1958
Creator: Hansen, Arthur G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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On the Flutter of Cylindrical Shells and Panels Moving in a Flow of Gas

Description: The equations of shells are taken in the form of the general technical theory of shallow shells and shells of medium length. The aerodynamic forces acting on a shell are taken into account only as forces of excess pressure according to the formula proposed by A.A. Iliushin in reference 3.
Date: September 1958
Creator: Stepanov, R. D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Theory and Experiments on Supersonic Air-to-Air Ejectors

Description: A comparison of experiment with theory is made for air ejectors having cylindrical mixing sections and operating under conditions of supersonic primary flow and either mixed or supersonic regimes of mixing. The effect on ejector performance of such parameters as mixer length and cross section, terminating diffuser, primary Mach number, and primary nozzle position is presented in terms of mass flow and pressure ratio.
Date: September 1958
Creator: Fabri, J. & Paulon, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Turbulent Boundary Layer on a Rough Curvilinear Surface

Description: "A number of semiempirical approximate methods exist for determining the characteristics of the turbulent boundary layer on a curvilinear surface. At present, among these methods, the one proposed by L. G. Loitsianskii is given frequent practical application. This method is sufficiently effective and permits, in the case of wing profiles with technically smooth surfaces, calculating the basic characteristics of the boundary layer and the values of the overall drag with an accuracy which suffice… more
Date: September 1958
Creator: Droblenkov, V. F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Principles of Turbulent Heat Transfer

Description: "The literature on turbulent heat transfer has in the course of years attained a considerable volume. Since this very complicated problem has not as yet found a complete solution, further studies in this field may be expected. The heat engineer must therefore accommodate himself to a constantly increasing number of theories and formulas. Since the theories generally start from hypothetical assumptions, and since they contain true and false assertions, verified knowledge and pure suppositions of… more
Date: September 1957
Creator: Reichardt, H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Finite Span Wings in Compressible Flow

Description: Equations are developed using the source distribution method for the velocity potential function and pressure on thin wings in steady and unsteady motion. Closed form solutions are given for harmonically oscillating wings of general plan form including the effect of the wing wake. Some useful examples are presented in an appendix for arrow, semielliptical, and hexagonal plan form wings.
Date: September 1956
Creator: Krasilschchikova, E. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Optimum Flight Paths of Turbojet Aircraft

Description: "The climb of turbojet aircraft is analyzed and discussed including the accelerations. Three particular flight performances are examined: minimum time of climb, climb with minimum fuel consumption, and steepest climb. The theoretical results obtained from a previous study are put in a form that is suitable for application on the following simplifying assumptions: the Mach number is considered an independent variable instead of the velocity; the variations of the airplane mass due to fuel consum… more
Date: September 1955
Creator: Miele, Angelo
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Theory of Dynamic Creep

Description: An analysis is given of the causes of the increase in the creep of a material under dynamic loads. A theory of dynamic creep is proposed based on the after-effect theory of Becker. Three circumstances that must be taken into account when theoretically treating dynamic creep are provided.
Date: September 1955
Creator: Predvoditelev, A. A. & Smirnov, B. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Kinetic Treatment of the Nucleation in Supersaturated Vapors

Description: The equations of the individual processes of self nucleation are utilized through an electrical analogy to obtain the nucleation frequency. This process is shown to be shorter and less subject to error than that of previous investigators since the appearance of indeterminant integration constants is completely avoided. With the nucleation frequencies of crystals and spheres the Ostwald law of stages is reviewed and modified.
Date: September 1954
Creator: Becker, R. & Döring, Werner
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Analytical Study of Shimmy of Airplane Wheels

Description: The problem of shimmy of a castering wheel, such as the nose wheel of a tricycle gear airplane, is treated analytically. The flexibility of the tire is considered to be the primary cause of shimmy. The rather simple theory developed agrees rather well with previous experimental results. The author suggests that shimmy may be eliminated through a suitable choice of landing gear dimensions in lieu of a damper.
Date: September 1952
Creator: Bourcier de Carbon, Christian
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Excitation of Unstable Perturbations in a Laminar Friction Layer

Description: "With the aid of the method of small oscillations which was used successfully in the investigation of the stability of laminar velocity distributions in the presence of two-dimensional perturbations, the excitation of the unstable perturbations for the Hartree velocity distributions occurring in plane boundary-layer flow for decreasing and increasing pressure is calculated as a supplement to a former report. The results of this investigation are to make a contribution toward calculation of the … more
Date: September 1952
Creator: Pretsch, Joachim
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Transition Caused by the Laminar Flow Separation

Description: An experimental investigation of the effects of the geometry of body surface, Reynolds number, stream turbulence, and a roughness element (wire) on the reattachment of separated laminar boundary-layer flow on a bent flat plate is presented and discussed. The flow mechanisms determining reattachment of the boundary layer are analyzed and discussed.
Date: September 1952
Creator: Maekawa, T. & Atsumi, Shoichi
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Behavior of Fast Moving Flow of Compressible Gas in Cylindrical Pipe in Presence of Cooling

Description: For compressible flow with friction in a cylindrical pipe the momentum, continuity, and heat-transfer equations are examined to determine whether an increase in Mach number ("thermal" Laval nozzle) is obtainable through heat conduction from the gas through the pipe walls. The analysis is based on the assumption that the wall temperature is negligibly small in comparison with the stagnation temperature of the gas. The analysis leads to a negative result. When the gas cooling is increased by also… more
Date: September 1951
Creator: Varshavsky, G. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Generalization of Joukowski formula to an airfoil of a cascade in compressible gas stream with subsonic velocities

Description: It is shown that the ordinary Joukowski formula for lift force of cascade blades in incompressible flow can be applied to the case of subsonic compressible flow with sufficient accuracy, provided that the density in the formula is taken as the arithmetic mean of the densities far ahead of and behind the cascade.
Date: September 1951
Creator: Loitsianskii, L. G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Isentropic Phase Changes in Dissociating Gases and the Method of Sound Dispersion for the Investigation of Homogeneous Gas Reactions With Very High Speed

Description: The analytical results of Part I are also applied to sound dispersion by friction and heat conduction, An irreversible change of momentum, energy, and type of particle corresponding to friction, heat conduction, and diffusion effects can appear both in the direction of the sound field and traverse to it. Longitudinal damping, the coupling of longitudinal damping and that due to chemical and physical changes, and coupling of diffusion and compositional changes are treated for a plane sound wave … more
Date: September 1950
Creator: Damköehler, Gerhard
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Report on Investigation of Developed Turbulence

Description: "The recent experiments by Jakob and Erk, on the resistance of flowing water in smooth pipes, which are in good agreement with earlier measurements by Stenton and Pannell, have caused me to change my opinion that the empirical Blasius law (resistance proportional to the 7/4 power of the mean velocity) was applicable up to arbitrarily high Reynolds numbers. According to the new tests the exponent approaches 2 with increasing Reynolds number, where it remains an open question whether or not a spe… more
Date: September 19, 1949
Creator: Prandtl, L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Behavior of the Laminar Boundary Layer for Periodically Oscillating Pressure Variation

Description: "The calculation of the phenomena within the boundary layer of bodies immersed in a flow underwent a decisive development on the basis of L. Prandtl's trains of thought, stated more than forth years ago, and by numerous later treatises again and again touching upon them. The requirements of the steadily improving aerodynamics of airplanes have greatly increased with the passing of time and recently research became particularly interested in such phenomena in the boundary layer as are caused by … more
Date: September 1949
Creator: Quick, August Wilhelm & Schröder, K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Investigations on the Stability, Oscillation, and Stress Conditions of Airplanes with Tab Control: First Partial Report. Derivation of the Equations of Motion and their General Solutions

Description: "For the design and the construction of airplanes the control is of special significance, not only with regard to the flight mechanical properties but also for the proportional arrangement of wing unit, fuselage, and tail unit. Whereas these problems may be regarded as solved for direct control of airplane motions, that is, for immediate operation of the control surfaces, they are not clarified as to oscillations, stability, and stress phenomena occurring in flight motions with Indirect control… more
Date: September 1949
Creator: Filzek, B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Investigations on the Stability, Oscillation, and Stress Conditions of Airplanes With Tab Control: Second Partial Report: Application of the Solutions Obtained in the First Partial Report to Tab-Controlled Airplanes

Description: The first partial report, FB 2000, contained a discussion of the derivation of the equations of motion and their solutions for a tab-controlled airplane; the results obtained there are now to be applied to the longitudinal motion of tab-controlled airplanes. In view of the abundance of structural factors and aerodynamic parameters, a general discussion of the problems is unfeasible. Thus it is demonstrated on the basis of examples what stability, oscillation, and stress conditions are to be exp… more
Date: September 1949
Creator: Filzek, B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Theory of Characteristics

Description: The theory of characteristics will be presented generally for quasilinear differential equations of the second order in two variables. This is necessary because of the manifold requirements to be demanded from the theory of characteristics.
Date: September 1949
Creator: Tollmien, W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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