Engineering Commons^™

Effect Of Precursor Heating On Radiating And Chemically Reacting Viscous Flow Around A Jovian Entry Body, Kuo Yen Szema

Mechanical & Aerospace Engineering Theses & Dissertations

The influence of changes in the precursor region flow properties (resulting from absorption of the radiation from the shock layer) on the entire shock layer flow phenomena around a Jovian entry body is investigated under physically realistic conditions. In the precursor region, the flow is considered to be inviscid and the variations in flow properties are determined by employing the small perturbation technique as well as the thin layer approximation. The flow in the shock layer is assumed to be steady, axisymmetric and viscous. The analysis is carried out by considering both the chemical equilibrium and nonequilibrium composition of the …

Design, Calibration, And Application Of A Sensor For Measuring Time Dependent Angle Of Attack Of Helicopter Blades, Weiyuan Henry Liu

Mechanical & Aerospace Engineering Theses & Dissertations

Various pressure probes were designed and tested which could be attached to helicopter blades when a helicopter is in flight. The pressure probes consisted of spherical heads which were held in place by cylindrical shanks. Built inside the heads were transducers to measure the pressure differential between pressure ports which were located on the front portion of the spherical head facing the airstream. Data was obtained over a range of airstream velocity of 11,6 to 88.4- m/s (38 to 290 ft/sec), corresponding to Reynolds numbers of 0.24 to 1.84x10⁵ based on the sphere diameter. Both static and dynamic tests …

Crack Propagation In Aluminum Sheets Reinforced With Boron-Epoxy, George Lawrence Roderick

Mechanical & Aerospace Engineering Theses & Dissertations

The literature has shown that crack propagation in cracked metal sheets can be significantly reduced by bonding an uncracked reinforcement to the metal sheet. However, cyclic debonding typically occurs over a localized area near the crack. Herein, an analysis was developed to predict both the crack growth and debond growth in a reinforced system. The analysis was based on the use of complex variable Green's functions for cracked, isotropic sheets and uncracked, orthotropic sheets to calculate inplane and interlaminar stresses, stress intensities and strain-energy-release rates. An iterative solution was developed that used the stress intensities and strain-energy-release rates to predict …

Analysis Of Moisture Absorption And Diffusion In Fiber Reinforced Polymeric Resin-Matrix Composite Materials, Stephen Stern Tompkins

Mechanical & Aerospace Engineering Theses & Dissertations

The diffusion of moisture through fiber reinforced polymeric-matrix composite materials has been studied analytically. The diffusion in the orthotropic, nonhomogeneous material was modeled, in detail, with a two-dimensional transient diffusion analysis. An effective diffusivity for the composite was determined in terms of the fiber volume fraction and the resin diffusivity. This effective diffusivity is in better agreement with recent data than those previously determined using less complex models.

The influence of both material and environmental parameters on the moisture content of the composite was determined analytically. Predicted moisture contents were compared over a wide range of values for emittance, solar …