Aerospace Engineering Commons^™

Deformation Produced By A Simple Tensile Load In An Isotropic Elastic Body, R. C. Batra

Mechanical and Aerospace Engineering Faculty Research & Creative Works

It is shown that a simple tensile load produces a simple extension provided the empirical inequalities (Truesdell and Noll [1], eqn. 51.27) hold. © 1976 Noordhoff International Publishing.

Bit Penetration Into Rock-A Finite Element Study, J. K. Wang, T. F. Lehnhoff

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The sequence of rock failure mechanisms and quantitative information on stress, displacement and material failure in the process of bit penetration have been obtained through computer simulation. A finite element approach has been developed to simulate bit penetration from bit-rock interaction to chip formation. A mathematical rock failure model, based on available rock failure experiments, has been proposed to represent post-failure rock behavior and applied in the penetration simulations. The finite element code was developed for two-dimensional plane strain problems to consider non-linear material properties, geometric non-linearity, and fracture propagation. An anistropic element as well as variable stiffness and stress …

Numerical Simulation Of A Widely Used Cloud Nucleus Counter., Darryl J. Alofs, J. C. Carstens

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The Performance of the Conventional Horizontal Plate Thermal Diffusion Chamber as a Cloud Nucleus Counter Was Studied. Numerical Calculations Were Performed in Order to Follow the Simultaneous Drop Growth and Sedimentation in the Spatially and Temporally Nonuniform Supersaturation Field. the Effect of Nuclei Distribution and Smallest Detectable Drop Size Were Investigated. the Results Indicate Order of Magnitude Uncertainty in the Count at 0. 1% Supersaturation, and a Factor of 2 Uncertainty at 1. 0% Supersaturation.

Mie Scattering Computations For Moderately Large Spherical Particles, Dwight C. Look

Mechanical and Aerospace Engineering Faculty Research & Creative Works

No abstract provided.

The Effects Of Main-Flow Radial Velocity On The Stability Of Developing Laminar Pipe Flow, F. C.T. Shen, T. S. Chen, L. M. Huang

Mechanical and Aerospace Engineering Faculty Research & Creative Works

In studying the stability due to axisymmetric disturbances of the developing flow of an incompressible fluid in the entrance region of a circular tube, a generalized version of the Orr-Sommerfeld equation was derived which takes account of the radial velocity component in the main flow. The new terms in the generalized Orr-Sommerfeld equation are inversely proportional to the Reynolds number. The resulting eigenvalue problem consisting of the disturbance equation and the boundary conditions was solved by a direct numerical integration scheme along with an iteration procedure. Neutral stability curves and critical Reynolds numbers at various axial locations are presented. A …

Apollo/Soyuz Tv Guide: "Soyuz, Soyuz, This Is Apollo...", Bob Button

Articles

This is a TV Guide from 1975 that features a story about the televised Apollo/Soyuz mission.

Analysis Of Spread Multi-Jet Vtol Aircraft In Hover, Leroy F. Albang

Mechanical & Aerospace Engineering Theses & Dissertations

An investigation of VTOL aircraft lift losses in hover has been conducted to evaluate a method for a simplified test technique. Three flat plate models were tested to determine their usefulness in predicting hover characteristics by comparing results between plate and three­ dimensional models. Attempts to correlate the out of ground effect results for the plate models with the empirical expression for calculating jet-induced loads were successful for the models which used engine simulators producing efflux characteristics similar to the three­ dimensional model engines. Data for the model using engine simulators with characteristics unlike those of the three-dimensional model simulators …

An Experimental Investigation Of A Cold Jet With Solid Centerbody Emitting From A Flat Plate Into A Subsonic Free Stream, Danny K. Livingston

Mechanical & Aerospace Engineering Theses & Dissertations

A study of the influence of a solid center body on lift loss and pitching moment has been conducted. It has been well established that a round free jet emitted from a flat plate at right angles to a cross flow causes an induced pressure distribution on the plate which adversely affects the lift and pitching stability of the flat plate.

This investigation has employed a 2.58 - cm diameter round jet with a 1.91 - cm diameter solid rounded core in order to modify the induced flow field and attempt to reduce the lift loss and pitching moment. Preliminary …

The Application Of Impact Dampers To Continuous Systems, Ranjit K. Roy, Richard D. Rocke, J. Earl Foster

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A study has been made of the application of impact dampers to two types of continuous systems, a simply supported and a clamped beam. Experimental models were tested in the laboratory and computer programs were developed to calculate response by two separate approaches. Results from calculations agreed favorably with experimental tests. Curves presented show the response to be expected for values of significant system parameters and enable the user to apply impact dampers to these types of continuous systems. © 1975 by ASME.

Thermal Stresses In A Sphere Due To Local Heating Followed By Complete Cooling, T. S. Chen, K. Thirumalai, J. B. Cheung

Mechanical and Aerospace Engineering Faculty Research & Creative Works

No abstract provided.

Photoionization Of The 6p32,122 Fine-Structure Levels In Cesium, Kaare J. Nygaard, Robert E. Hebner, James A. Jones, Robert J. Corbin

Physics Faculty Research & Creative Works

The relative photoionization cross sections for cesium atoms selectively excited to the 6P32,122 states have been measured in a triple-crossed-beam experiment. A cesium discharge lamp produced resonant wavelengths of 8521 and 8944 for the excitation process. A Hg-Xe lamp combined with a grating monochromator was used for the actual ionization in the wavelength region from 2500 to 5000. Background counts due to photoionization of ground-state cesium atoms and dimers as well as various surface effects were discriminated against by chopping the excitation light source. The data are compared with results from radiative-recombination measurements in which the fine-structure levels are not …

"Thomas Stafford" - Astronauts & Cosmonauts Cultural Exchange Album, Thomas P. Stafford

Articles

This is a photo album of the cultural exchange visit between the American astronauts and Soviet cosmonauts of the Apollo-Soyuz Mission.

The front cover reads "Thomas Stafford"

Apollo Soyuz Test Project - Press Kit, Nasa

Articles

COSMONAUTS, ASTRONAUTS TO MEET IN SPACE

Two manned spacecraft will be launched into Earth orbit July 15 -- one from Merritt Island, Florida, and the other from Central Asia -- to bring into reality the May 1972 agreement between the United States and the Soviet Union to work toward a common docking system for future generations of spacecraft.

Unless stated otherwise within this repository collection, all materials are shared under the following Creative Commons license: [Creative Commons Attribution-NonCommercial 4.0 International License].

Experimental Investigation Of Supporting Wire Interference Effects In The Supersonic Near Wakes Of Slender Bodies., Dale M. Pitt

Masters Theses

"It is generally recognized that the presence of a model support sting i s likely to affect the model's base pressure and wake characteristics. The use of a wire-supported model is usually relied upon to obtain minimum disturbance measurements in the model's wake. Investigations into the disturbances caused by different size supporting wires have been conducted with the use of a 16-degree wedge and cone. The tests were conducted in the University of Missouri-Rolla axisymmetric supersonic wind tunnel at Mach 3.15, and at a Reynolds number of 2.14 X 10⁶ per inch. Pitot pressure traverses were made in the …

A Study Of The Potential Performance Improvements Available From The Ga(W)-1 Airfoil As Compared To The Naca 2412 Airfoil., Robert Keith Rice

Masters Theses

"A direct comparison of the current NACA 2412 section general aviation airfoil and the recently developed GA(W)-1 airfoil was conducted in the University of Missouri - Rolla's subsonic wind tunnel. Finite aspect ratio performance of both airfoils equipped with 30 percent chord flaps was studied to predict possible performance gains for general aviation aircraft available from the GA(W)-1 section.

Results show that the NACA 2412 airfoil with a standard slotted type flap gives a maximum lift coefficient of 1.88 with the flap deflected 30 degrees and a test Reynolds number of 4.Sxl0 5 based on wing chord. The GA(W)-1 section …

A Parametric Investigation Of The Validity Of 1/25 Scale Automobile Aerodynamic Testing., Marvin Eugene Doberenz

Masters Theses

"Wind tunnel tests have been performed measuring the aerodynamic forces and underbody boundary layer profiles for 1/25 scale models. The trends of the force coefficients with Reynolds number, the underbody boundary layer profiles, and the influence of the ground plane boundary layer on the force coefficients of small-scale models has been shown to be similar with previous results from larger models. This study has shown the usefulness of small-scale models for parametric studies of automobile aerodynamics. The agreement of the data with previous results, also supports the possih1lity o f a method of correction for boundary layer growth on fixed …

Insoluble Condensation Nuclei: The Effect Of Contact Angle, Surface Roughness And Adsorption., P. C. Mahata, Darryl J. Alofs

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Condensation of Water Vapor on Various Surfaces Was Studied Experimentally. for Surfaces with an Air-Water Contact Angle Theta Less Than 20 Degree, the Experimentally Determined Values of Critical Supersaturation S//c Agreed with Those Given by the Volmer Theory. at Higher Theta, the Experimental Values of S//c Were Below the Volmer Theory Values. When the Applied Supersaturation Was Less Than S//c, Condensation Was Avoided for Periods as Long as 20 H. It Was Determined Both by Experiment and Theoretical Analysis that the Effect of Surface Roughness is to Decrease S//c Only Slightly. These Results Suggest that Most Insoluble Airborne Particles Are …

Measurement Of Growth Rate To Determine Condensation Coefficients For Water Drops Grown On Natural Cloud Nuclei., A. M. Sinnarwalla, Darryl J. Alofs, J. C. Carstens

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Growth Rate Measurements Were Made for Water Drops Grown on Nuclei in Atmospheric Air Samples Taken in Rolla, Missouri. Rolla, Having a Population of 15,000 and Very Little Industry, is Relatively Free of Urban Pollutants. the Measurements Were Made in a Vertical Flow Thermal Diffusion Chamber at Supersaturations of 0. 5 and 1%. the Time to Grow from Near Dry Radius to the Final Radius (6 to 7. 5 Mu M) Was Measured. If One Assumes the Thermal Accomodation Coefficient is Unity, the Measurements Indicate an Average Value of 0. 026 for the Condensation Coefficient. the Temperature Ranged from 22. …

Transport Phenomena In Thermally Stratified Boundary Layers, D. W. Pepper, S. C. Lee

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Studies of heat, mass, and momentum transfer are made to analyze the formation of marine fogs in thermally stratified boundary layers in the atmosphere. The governing partial differential equations of continuity, momentum, temperature, and concentration are used to describe the transport phenomena. An additional equation of turbulence energy is introduced to account for the development of the turbulent motions. Simultaneous solution of this system of equations allows the turbulent exchange coefficients to be treated in the same way as all other dependent parameters. Verification of the theoretical approach is made by comparing the numerical predictions with wind tunnel simulations of …

Faa/Dod Liaison In Management Of The National Aviation System, Ronald S. Brooks, Jerry L. Beatty

Theses and Dissertations

This study describes and analyzes military and FAA liaison efforts which impact on the management of the National Aviation System. It begins with the historical development of the National Airspace System (NAS), The system is evolutionary in nature and most innovations have come from user demands and outside sources, Long term government responsibility to manage the system has been secondary to the operation and maintenance functions, There has been duplication of effort due to poor coordination on developing common goals, The military has been the leader in developing technology that led to improvement of the system.

Dynamics Of Explosion Remnants In Earth-Orbits, Joseph T. Fuss

Mechanical & Aerospace Engineering Theses & Dissertations

Explosions in space produce particles that are hazardous to space vehicles. Some of these particles are not trackable and their locations must be predicted by dynamical methods.

This investigation sheds light on three different, areas, First, ignoring perturbations, the characteristics of a three dimensional envelope outlined by the sum of individual particle orbits is determined, Second, the distribution of the particles is found as a function of time, Finally, the movement, of the body via secular perturbations is investigated. Magnitudes of the explosion, the point of. detonation in the parent satellite's orbit, and the radius of perigee of the parent …

Ua66/1/2 Scrapbook, Wku Ogden College Of Science & Engineering

WKU Administration Documents

Scrapbook of clippings, press releases, photographs and other items related to the history of Ogden College of Science & Technology from 1961 to 1974.

Experimental Determination Of Improved Aerodynamic Characteristics Utilizing Biplane Wing Configurations, Elmer Carl Olson

Masters Theses

"Improving the aerodynamic characteristics of an airplane with respect to a higher lift coefficient, a lower drag coefficient and a higher lift over drag ratio as a function of angle of attack will make it more efficient, thus conserving energy or improving performance. Investigations were carried out to determine if the aerodynamic characteristics of biplane wing systems could be made more efficient, for low subsonic speeds, than a monoplane of comparable area and aspect ratio. A variable position three-dimensional biplane wing system, and a fuselage that could be fitted with a monoplane wing or the variable position biplane wing system …

Transient Thermal Stresses In A Sphere By Local Heating, J. B. Cheung, T. S. Chen, K. Thirumalai

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The problem of transient thermal stresses in a solid, elastic, homogeneous, and isotropic sphere is solved for uniform and nonuniform, local surface heating. The temperature solutions are obtained by using separation of variables and integral transformation. The corresponding thermal stresses are derived by superposing a particular displacement potential function on Boussinesq solutions. Numerical solutions for two particular cases of localized heating of a typical brittle spherical solid have been obtained and presented. The results indicate a tensile stress concentration in the interior of the solid below the heated zone. © 1974 by ASME.

Vibration Characteristics Of Free Thin Cylindrical Shells, Floyd M. Cunningham, D. E. Leanhardt

Mechanical and Aerospace Engineering Faculty Research & Creative Works

This paper considers the flexural vibrations of free thin circular cylinders. A frequency equation is derived using free-free characteristic beam functions to represent the variation of mid-surface shell displacement components, u, v and w, with respect to the axial direction. Timoshenko strain-displacement relations for thin cylinders are used to determine elastic vibratory strain energy. Energy methods are applied to obtain the frequency equation and associated amplitude ratios for each of its roots. This energy solution is checked experimentally using a vibration exciter and numerically using the SABOR IV finite element program. With minor modification, the frequency equation conforms to the …

Computer-Aided Design Of Light Aircraft To Meet Certain Aerodynamic And Structural Requirements, Joanne Lynn Walsh

Mechanical & Aerospace Engineering Theses & Dissertations

Nonlinear mathematical programming techniques are applied to a particular aircraft design problem, that of determining the maximum range design for light aircraft subject to certain aerodynamic and structural requirements. Search techniques available in an existing nonlinear optimization computer program, AESOP, are applied to the design problem. Seven design variables are used to define the wing dimensions, the wing skin thickness, the cruise velocity, the amount of fuel carried, and the engine horsepower. The influence of different design requirements on the range is observed and discussed.

A Study On Conical Rocket Stabilization, Thomas Dombeck

Journal of the Minnesota Academy of Science

The objective was to develop a finless model rocket . The idea evolved after seeing the Army's Sprint anti-ballistic missile, which is conical in shape and does not have fins for primary aerodynamic stabilization . In designing the model rocket, a scale drawing was made, and center of gravity (CG) and center of pressure (CP) computations transferred to it. The initial design proved unstable because the CG and CP were too close together. Another drawing was made with the addition of a payload section to carry necessary weight to allow moving the CG forward. This second design was mathematically stable. …

Breakdown Of The Laminar Flow Regime In Permeable-Walled Ducts, E. M. Sparrow, G. S. Beavers, T. S. Chen, J. R. Lloyd

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The stability of laminar flow in a parallel-plate channel having one permeable bounding wall is investigated by means of linear theory. The analysis lakes account of the coupling of the disturbance, fields in the channel and in the permeable material and of velocity slip at the surface of the permeable wall. Complementary experiments are performed in which the breakdown of the laminar regime in flat rectangular ducts is identified from pressure-drop measurements and from flow visualization studies. The experiments cover the range of slip velocities from 15-30 percent of the mean velocity and, in addition, the case of zero slip …

Decision-Directed Detector For Overlapping Pcm/Nrz Signals, Cheng Wang, Thomas L. Noack

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A decision-directed (DD) technique for the detection of overlapping PCM/NRZ signals in the presence of white Gaussian noise is investigated. The performance of the DD detector is represented by probability of error PE versus input signal-to-noise ratio (SNR). To examine how much improvement in performance can be achieved with this technique, PE's with and without DD feedback are evaluated in parallel. Further, analytical results are compared with those found by Monte Carlo simulations. The results are shown in good agreement. © 1973, IEEE. All rights reserved.

Parametric Resonance Of A Beam Subjected To A Sawtooth, Axial Force, Alfred George Richardson

Masters Theses

"This study considers the response of a perfectly elastic straight beam subjected to a periodic, non-harmonic, axial load. A two-mode solution is sought and the effects of axial inertia are included in the analysis. General equations of motion for the beam are developed and their stability is studied with the aid of an analog computer. Results are presented in graphical form. Regions of instability are defined for both modes. A region of combination resonance is also found to occur for the case of a two-mode solution with axial inertia. Typical response curves are presented and the effects of axial inertia …