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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Swirling flows in conical vessels

Ferguson, John William James January 1989 (has links)
No description available.
2

The effects of groynes on river flow

Pattanaik, Akshayabandhu January 1966 (has links)
Existing knowledge of the flow in a river past a groyne is inadequate to explain fully the siltation and scour that take place around such a structure. A survey of published material reveals controversy over the choice of pertinent flow parameters affecting the maximum scour depth.
3

Depth averaged and RANS modeling of open channel flow

Zobeyer , A T M HASAN Unknown Date
No description available.
4

A model for transition by attachment line contamination and an examination of cross-flow instability in three-dimensional boundary layers

Stewart, I. J. January 1987 (has links)
No description available.
5

Laryngeal source excitation modelling

Pereira, J. C. January 1987 (has links)
No description available.
6

The mathematical modelling of cascading rotary dryers

Langrish, Timothy Alan Granville January 1988 (has links)
No description available.
7

Compressible discharge coefficients of branching flows

Yip, C. W. H. January 1988 (has links)
A two-dimensional numerical model for compressible branching flow through a slot is described for the purpose of predicting the discharge coefficients of film cooling holes in gas turbine blades. The method employs free-streamline theory and the hodograph transformation. It calculates the area ratio of hole to duct and the contraction coefficient from a set of prescribed boundary conditions. An approximate method for calculating the compressible contraction coefficients is also discussed in the thesis. It employs the incompressible theory previously developed by McNown and Hsu (1951) for the free efflux, the 'compressibility factor' and the flow parameter (P<sub>o</sub>-P<sub>j</sub>)/(P<sub>o</sub>-P<sub>1</sub>), where P<sub>o</sub>, P<sub>j</sub>, P<sub>1</sub> represent the stagnation pressure, the static pressure of the jet and the static pressure of the approach flow, respectively. The advantages of using this method are the direct input of the area ratio of hole to duct and its speed of calculation. Experimental tests were performed using a specially designed rig in a supersonic wind tunnel. The investigations included sharp-edged slots with three different widths, a single hole and a row of two holes. The approach velocity in terms of the characteristic Mach number ranged from 0.18 to 0.58 and the pressure ratio P<sub>o</sub>/P<sub>j</sub>, ranged from 1.10 to 1.97. Agreement between the experimental data and the theoretical values was good to within the experimental accuracy (typically around +/- 5%) for the slots and the 2-hole configuration. For the 1-hole configuration, less bleed flow than predicted was observed, with the discrepancy varying from 7% to 18%. The latter case is a very severe test of a purely two-dimensional theory. The results for the 2-hole plate suggest that the slot theory can in fact be used to predict the flow through a row of holes with small pitch to diameter ratios.
8

Unsteady gas flow in the manifolds of multicylinder automotive engines

Bingham, J. F. January 1983 (has links)
No description available.
9

Power Consumption Models for Streaming on Mobile Terminals with On-Off Characteristics

Godavarthi, Nandini Chowdary January 2016 (has links)
The usage of smartphones has been increasing with surprising speed. These smartphones are popular for delivery of video content. The main drawbacks of these smartphones are battery life and video freezing. Despite, while streaming a video it consumes large of amount of power affecting QoE. So, in this case we considered streaming a video from server to mobile client involving ONOFF characteristics. While streaming, there exists some transition delay while switching the power states and the effect of these transition delays might affect instantaneous power consumption of the smartphone. Henceforth, this thesis aims to determine the effect on instantaneous power consumption from distributed state durations and transitions in exponential fluid flow model, for a streamed video. Power measurements along with ON and OFF times were measured with the help of a benchmark tool, Monsoon Power Monitor tool. VLQoE tool, a video streaming tool was used to present a two state model based on the inter-picture time, for the HTTP-based video streaming. Experiments were executed in a closed enclosure setup using a black-box to avoid external obstacles that might possibly affect the power consumption metrics. Considering these measurements, the effect on instantaneous power consumption stemming from the exponentially distributed state durations and transitions in the corresponding fluid flow model can be determined and modelled.
10

Modelling the impact of total stress changes on groundwater flow

Dissanayake, Nalinda 29 April 2008
The research study involved using the modified FEMWATER code to investigate the impact of total stress changes on groundwater flow in the vicinity of a salt tailings pile. Total stress and pore-pressure data observed at the Lanigan and Rocanville potash-mine sites were used to assist the development of a generic FEMWATER model. The original 3-D mesh considered for model study covers a region of 7.6 km x 7.6 km x 60 m. The simulated pile itself covers a surface area of 1.6 km x 1.6 km within the region. Symmetry of the idealized system allowed half of the system to be modelled to reduce the size of the mesh. The model was layered to facilitate different materials representing different hydrostratigraphic scenarios. The GMS-release of the FEMWATER code (version 2.1) was modified to simulate the pore-pressure response to total stress changes caused by tailings pile loading at the ground surface to be modelled. The modified code was verified before applying to present study.<p>Long-term pore pressure generation and dissipation due to pile construction was investigated for eleven hydrostratigraphic scenarios consisting of plastic clays, stiff till and dense sand layers commonly found in Saskatchewan potash mining regions. The model was run for two distinctive pile loading patterns. Model results indicated that the loading pattern has a significant influence on pore pressure generation beneath the pile. The model was initially run for 30 year pile construction period and later simulated for 15, 25 and 35 year construction periods to investigate the impact of loading rate. These results showed that, as expected, the peak pore water pressure head is proportional to the pile construction rate. A sensitivity analysis, which was carried out by changing hydraulic conductivity of stiff till, revealed that the lower the hydraulic conductivity, the greater the pore pressure generation beneath the pile.<p>Overall, the research study helped to understand and predict the influence of pile construction and hydrostratigraphy on pore-pressure changes beneath salt tailing piles. Low K/Ss or cv materials (compressible tills) demonstrate a slow dissipation rate and high excess pressures. Compared to dense sand which has very high K/Ss, till has very low K/Ss which causes in high excess pore pressure generation. Sand layers act as drains, rapidly dissipating pore pressures. Thicker low K/Ss units result in slower dissipation and higher pressures. As the thickness of the low K/Ss layer increases, the peak pressures increase as the drainage path lengthens. Thin plastic clay layers give rise to the highest pressures.<p>The model study showed that hydrostratigraphic scenarios similar to those found at Saskatchewan potash mine sites can generate the high pore pressures observed in the vicinity of salt tailings piles as a result of pile loading. Peak pressures are very sensitive to pile construction rates, loading patterns and hydrostratiagraphy of the region. Peak pressures can reach levels that would be of concern for pile stability on the presence of adverse geological conditions.

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