Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 11 of 11 for “"Compression-expansion"”.
-
Positive Symmetric Solutions Of A Boundary Value Problem With Dirichlet Boundary Conditions
<p>We apply a recent extension of a compression-expansion fixed point theorem of function type to a second order boundary value problem with Dirichlet boundary conditions. We show the existence of positive symmetric solutions of this boundary value problem. </p>
-
Gas dynamic and acoustic interactions with supersonic free shear layers
… pressure gradient parameter across the compression/expansion waves. The convection speed of the large-scale structures in pressure matched flows was found to be higher than that predicted by the isentropic relations, whereas for the pressure mismatched cases the convection speeds were …
-
An approach for the separation of voices in composite musical signals
… concrete, noise reduction, and time-scale compression/expansion. This material is based upon work supported, in part, under a National Science Foundation Graduate Fellowship. Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author and do …
-
Novel all-optical switching and processing techniques for optical networking
… in a dispersive medium. Apart from the packet compression/expansion experiments, demultiplexing and channel add/drop multiplexing of 40-Gb/s OTDM signals were also experimentally demonstrated. The technological challenges of implementing this technique at higher repetition rates are discussed.
-
Piston ring design for reduced friction in modern internal combustion engines
… as the top ring around top dead center of the compression/expansion strokes and the oil control ring throughout the engine cycle. Model predictions indicated that the top ring friction could be reduced by implementing a skewed barrel profile design or an upward piston groove tilt design, and …
-
Sonocrystallization and sonofragmentation
… breakage from defects formed by shock-induced compression-expansion of the initial crystal and particle breakage from defects created during shock-induced bending or torsion of the initial crystal. In Chapters 4 and 5, the sonocrystallization of pharmaceutical agents having inherently low water …
-
Analysis and optimisation of thermal energy storage
… as a heat engine. The heat pumps/engines require compression and expansion devices, for which simple models are described and are integrated with the packed bed models. The PTES system behaviour is investigated with parametric studies, and alternative design configurations are explored. A …
-
Modelling and development of thermo-mechanical energy storage
… Generally, the same strategies that minimise compression/expansion losses also maximise heat exchanger losses, which results in optimal points at certain operating conditions. A numerical model is developed to find these optima while accounting for real fluid properties. Employing a …
-
Mathematical modelling of flow and combustion in internal combustion engines
… k- model of turbulence to account for rapid compression/expansion, and on the k-W model also used in the computations. It is concluded that the standard k- model may lead to poor predictions when used for internal combustion engine simulations, and that the modified model leads to more …
-
Application of Phase Change Material to Improve Adiabatic Compressed Air Energy Storage System
… (about 50%) since a significant amount of the compression energy is lost as heat. Additionally, in the expansion process, this technology would require a non-renewable source of energy for heating the air to prevent frosting. To overcome this drawback, an adiabatic CAES (ACAES) system has been …
-
The fluid-structure interaction of an axisymmetric underexpanded jet flowing across an adjacent compliant surface
… in response to the restricted near-wall flow expansion, was observed in the schlieren imagery. This shock wave interacts with the barrel shock to cause the formation of a prominent shock/boundary-layer interaction (SBLI) near the wall, replacing the traditional first-cell Mach disk structure. …