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Poison ivy and poison sumac and their eradication.

Description: Describes the characteristics of poison ivy and poison sumac, the damage they cause, and methods of control and eradication; also provides remedies for ivy poisoning.
Date: 1940
Creator: Grant, C. V. (Charles Vincent), b. 1880.; Coville, Frederick V. (Frederick Vernon), 1867-1937.; Hansen, A. A.; Sievers, A. F. (Arthur Frederick), b. 1885. & Talbot, M. W. (Murrell Williams), b. 1889.
Partner: UNT Libraries Government Documents Department

Line Parameters and Computed Spectra for Water Vapor Bands at 2.7 mu

Description: From Foreword: "This Monograph is one of a series intended to provide fundamental information required for the estimation and interpretation of atmospheric transmittance at infrared frequencies. Part I of this Monograph presents the fundamental properties of the 2.7m water vapor band in terms of line absorptions and the integrated transmittance at any frequency for infinite resolution. Part II presents examples of the "degraded" transmittance for finite resolution, as a function of the spectral slit width, concentration, and pressure with which direct observations may be compared."
Date: August 3, 1964
Creator: Gates, David M.; Calfee, Robert F.; Hansen, David W. & Benedict, W. S.
Partner: UNT Libraries Government Documents Department

A numerical procedure for designing cascade blades with prescribed velocity distribution in incompressible potential flow

Description: Report presenting a step-by-step numerical procedure based on conformal-mapping theory for the design of a cascade of airfoils with a prescribed dimensionless-velocity distribution in incompressible potential flow. It includes a set of tables to serve as a guide in computation. A comparison of several different types of airfoil design are included to examine the reliability of the procedure.
Date: June 1950
Creator: Hansen, Arthur G. & Yohner, Peggy L.
Partner: UNT Libraries Government Documents Department

Condensation of air in supersonic wind tunnels and its effects on flow about models

Description: Report presenting the results of an investigation of condensation phenomena in supersonic wind tunnel. Lower and upper limits for the degree of supersaturation attainable before the onset of condensation of air are discussed. A method is presented for calculating the properties of a stream containing a small fraction of condensed air.
Date: April 1952
Creator: Hansen, C. Frederick & Nothwang, George J.
Partner: UNT Libraries Government Documents Department

X-ray instrumentation for density measurements in a supersonic flow field

Description: Report describing an instrument based on the principle that an x-ray beam is essentially undeviated while traversing a short path in air. It was used to measure the product of air density and the path length in the 10- by 14-inch supersonic wind tunnel. The measurements obtained were accomplished by comparing the intensity of two beams from the same X-ray source.
Date: December 1952
Creator: Dimeff, John; Hallet, Ralph K., Jr. & Hansen, C. Frederick
Partner: UNT Libraries Government Documents Department

Aerodynamic design of axial-flow compressors: Volume 3

Description: Chapters XI to XIII concern the unsteady compressor operation arising when compressor blade elements stall. The fields of compressor stall and surge are reviewed in Chapters XI and XII, respectively. The part-speed operating problem in high-pressure-ratio multistage axial-flow compressors is analyzed in Chapter XIII. Chapter XIV summarizes design methods and theories that extend beyond the simplified two-dimensional approach used previously in the report. Chapter XV extends this three-dimensional treatment by summarizing the literature on secondary flows and boundary layer effects. Charts for determining the effects of errors in design parameters and experimental measurements on compressor performance are given in Chapters XVI. Chapter XVII reviews existing literature on compressor and turbine matching techniques.
Date: August 1, 1956
Creator: Johnsen, Irving A.; Bullock, Robert O.; Graham, Robert W.; Costilow, Eleanor L.; Huppert, Merle C.; Benser, William A. et al.
Partner: UNT Libraries Government Documents Department

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 1, 1958
Creator: Hansen, Arthur G.
Partner: UNT Libraries Government Documents Department

A visualization study of secondary flows in cascades

Description: Flow-visualization techniques are employed to ascertain the streamline patterns of the nonpotential secondary flows in the boundary layers of cascades, and thereby to provide a basis for more extended analyses in turbomachines. The three-dimensional deflection of the end-wall boundary layer results in the formation of a vortex within each cascade passage. The size and tightness of the vortex generated depend upon the main-flow turning in the cascade passage. Once formed, a vortex resists turning in subsequent blade rows, with consequent unfavorable angles of attack and possible flow disturbances on the pressure surfaces of subsequent blade rows when the vortices impinge on these surfaces. Two major tip-clearance effects are observed, the formation of a tip-clearance vortex and the scraping effect of a blade with relative motion past the wall boundary layer. The flow patterns indicate methods for improving the blade tip-loading characteristics of compressors and of low- and high-speed turbulence.
Date: 1954
Creator: Herzig, Howard Z.; Hansen, Arthur G. & Costello, George R.
Partner: UNT Libraries Government Documents Department

Some numerical solutions of similarity equations for three-dimensional laminar incompressible boundary-layer flows

Description: From Summary: "Numerical solutions are presented for two classes of similarity equations corresponding to a range of three-dimensional boundary-layer flows. Equations for limiting-flow deflection and equations for the calculation of boundary-layer streamlines are also presented."
Date: September 1958
Creator: Yohner, Peggy L. & Hansen, Arthur G.
Partner: UNT Libraries Government Documents Department

Approximations for the thermodynamic and transport properties of high-temperature air

Description: Report presenting the thermodynamic and transport properties of high-temperature air in closed form starting from approximate partition functions for the major components in air and neglecting all minor components. The compressibility, energy, entropy, specific heats, speed of sound, coefficients of viscosity and thermal conductivity, and Prandtl numbers for air are provided for a range of temperatures and pressures.
Date: March 1958
Creator: Hansen, C. Frederick
Partner: UNT Libraries Government Documents Department

The erosion of meteors and high-speed vehicles in the upper atmosphere

Description: From Summary: "A simple inelastic collision model of meteor-atmosphere interaction is used and analytic relations for velocity, deceleration, size, and relative luminous magnitude of meteors are derived and expressed in dimensionless parametric form. The analysis is compared with available quantitative observations of meteor behavior and it is indicated that a large fraction of the atmospheric bombardment energy is used in eroding meteor material. The erosion from large, high-speed vehicles as they traverse the high-altitude, free-molecule portion of the atmosphere is calculated, on the assumption that the vaporization process is similar to that which occurs for meteors."
Date: March 1957
Creator: Hansen, C. Frederick
Partner: UNT Libraries Government Documents Department

A review of the thermodynamic, transport, and chemical reaction rate properties of high-temperature air

Description: Thermodynamic and transport properties of high temperature air, and the reaction rates for the important chemical processes which occur in air, are reviewed. Semiempirical, analytic expressions are presented for thermodynamic and transport properties of air. Examples are given illustrating the use of these properties to evaluate (1) equilibrium conditions following shock waves, (2) stagnation region heat flux to a blunt high-speed body, and (3) some chemical relaxation lengths in stagnation region flow.
Date: July 1958
Creator: Hansen, C. Frederick & Heims, Steve P.
Partner: UNT Libraries Government Documents Department

On possible similarity solutions for three-dimensional incompressible laminar boundary layers 2: similarity with respect to stationary polar coordinates

Description: From Summary: "Solutions of mainstream flow patterns for three-dimensional, laminar, incompressible thin-boundary-layer flows (over flat or slightly curved surfaces) having similarity with respect to stationary polar coordinates in the plane of the surface are derived. The solutions are summarized in a table."
Date: November 1956
Creator: Herzig, Howard Z. & Hansen, Arthur G.
Partner: UNT Libraries Government Documents Department

On possible similarity solutions for three-dimensional incompressible laminar boundary layers 1: similarity with respect to stationary rectangular coordinates

Description: From Summary: "Solutions of mainstream flow patterns for all possible incompressible laminar-boundary-layer flows having classical similarity with respect to rectangular coordinate systems are derived. These solutions, which apply to a wide range of flows, are summarized in table form."
Date: October 1956
Creator: Hansen, Arthur G. & Herzig, Howard Z.
Partner: UNT Libraries Government Documents Department

A survey of unclassified axial-flow-compressor literature

Description: A survey of unclassified axial-flow-compressor literature is presented in the form of brief reviews of the methods, results, and conclusions of selected reports. The reports are organized into several main categories with subdivisions, and frequent references are made within the individual reviews to pertinent material elsewhere in the survey.
Date: November 8, 1955
Creator: Herzig, Howard Z. & Hansen, Arthur G.
Partner: UNT Libraries Government Documents Department

On possible similarity solutions for three-dimensional incompressible laminar boundary layers 3: similarity with respect to stationary polar coordinates for small angle variation

Description: Report presenting approximate solutions describing mainstream flows confined to regions of small angle variation over flat surfaces for three-dimensional, laminar, incompressible, thin boundary-layer flows with similar with respect to stationary polar coordinate systems. Results regarding the mainstream, boundary layer, ordinary differential equations, and comparison with experiment are provided.
Date: January 1957
Creator: Herzig, Howard Z. & Hansen, Arthur G.
Partner: UNT Libraries Government Documents Department

Analysis of particle motions for a class of three-dimensional incompressible laminar boundary layers

Description: From Introduction: "Results obtained in the experimental investigations of secondary flows in turbomachines (refs. 1 to 3) indicate that information concerning three-dimensional laminar boundary-layer behavior can be of practical value in interpreting and correlating measurements of losses in the turbo-machines for design purposes. Reference 4 gives a theoretical analysis of the overturning (more than mainstream turning) of the three-dimensional laminar boundary layer developed on flat or nearly flat surfaces, under mainstream flows which consist of streamline translates (i.e., the entire streamline pattern can be obtained by translating any particular streamline pattern can be obtained by translating any particular streamline parallel to the leading edge, fig. 1) with constant axial velocity component."
Date: November 1956
Creator: Hansen, Arthur G. & Herzig, Howard Z.
Partner: UNT Libraries Government Documents Department

Cross flows in laminar incompressible boundary layers

Description: Report presenting an analysis derived for the three-dimensional boundary-layer flow over a flat surface with a leading edge under main-flow streamlines that are translates and representable by polynomial expressions. The boundary layers are laminar and incompressible and the profiles of their velocity components have similarity with respect to rectangular coordinates.
Date: February 1956
Creator: Hansen, Arthur G. & Herzig, Howard Z.
Partner: UNT Libraries Government Documents Department

Approximate solutions of a class of similarity equations for three-dimensional, laminar, incompressible boundary-layer flows

Description: Report presenting an analysis for obtaining approximate solutions of the similarity equations for three-dimensional laminar-boundary-layer flows over a flat surface under main-flow streamlines that are translates and representable as infinite series expansions.
Date: September 1958
Creator: Hansen, Arthur G. & Herzig, Howard Z.
Partner: UNT Libraries Government Documents Department

Theoretical and experimental investigation of the effect of yaw on heat transfer to circular cylinders in hypersonic flow

Description: Report presenting an approximate theory for predicting the rate of heat transfer to the stagnation region of blunt bodies in hypersonic flight. Attention is focused on the case where wall temperature is small compared to stagnation temperature. Experiments were conducted in the hypersonic gun tunnel to obtain a preliminary check on this theoretical prediction.
Date: July 25, 1955
Creator: Eggers, A. J., Jr.; Hansen, Frederick & Cunningham, Bernard E.
Partner: UNT Libraries Government Documents Department

Smoke studies of secondary flows in bends, tandem cascades, and high-turning configurations

Description: Flow-visualization studies, using smoke, were made of the secondary flows in rectangular bends, tandem cascades, and high-turning configurations. The roll-up of the wall boundary layer of a rectangular bend forms a passage vortex near the suction surface similar to that previously observed for cascades. The vortex so formed then shifts out into the main stream. Because of leading-edge effects, the boundary-layer flows in bends were found to be sufficiently different from the flows in blade rows to make direct application of bend results to blade rows inadvisable.
Date: March 11, 1953
Creator: Hansen, Arthur G.; Herzig, Howard Z. & Costello, George R.
Partner: UNT Libraries Government Documents Department

Stagnation-point heat transfer to blunt shapes in hypersonic flight, including effects of yaw

Description: An approximate theory is developed for predicting the rate of heat transfer to the stagnation region of blunt bodies in hypersonic flight. Attention is focused on the case where wall temperature is small compared to stagnation temperature. The theoretical heat-transfer rate at the stagnation point of a hemispherical body is found to agree with available experimental data. The effect of yaw on heat transfer to a cylindrical stagnation region is treated at some length, and it is predicted that large yaw should cause sizable reductions in heat-transfer rate.
Date: April 1958
Creator: Eggers, A. J., Jr.; Hansen, C. Frederick & Cunningham, Bernard E.
Partner: UNT Libraries Government Documents Department