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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

Towards a characteristic equation for permeability

Siddiqui, Adil Ahmed 10 October 2008 (has links)
The characterization of reservoir permeability (k) remains the elusive challenge in reservoir engineering. This work considers prior developments in an evolutionary sense, and, as with prior work, our goal is the development of a "characteristic permeability relation" (CPR). To this end, we have developed 5 CPR formulations -- 3 of which could be considered modifications of "historical" models and 2 of which are "weighted" power law-exponential models. In this work, we consider permeability to be only a function of two variables; k = f(ø,z) -- porosity (ø ) and z, where z is either the water saturation (Sw) or the Archie Formation Factor (F). Our rationale in considering k = f(ø,z) is two-fold -- first, such a formulation is a fundamental extension of the k = f( ø) correlation work by Archie (and countless others); and second, our validation datasets are limited to literature cases and cases obtained from industry sources -- none of which would be considered suitable for extension beyond porosity and another variable. We demonstrate and validate our concept of a characteristic permeability relation using various datasets obtained from the literature and from industry sources. In this work we show that each proposed relation has a unique character and performance -- depending on primarily on the data, rather than the functional form of the permeability relation. Using the characteristic permeability relations developed in this work -- the proposed permeability relations can be extended to other and other data types. It may also be possible to develop so-called "hydraulic flow unit" methods which segregate petrophysical data into depositional flow sequences.
2

A spectrophotometric analysis of dentinal leakage in the resected root a thesis submitted in partial fulfillment ... endodontics ... /

Ichesco, Wesley Richard. January 1986 (has links)
Thesis (M.S.)--University of Michigan, 1986.
3

Oxygen and water vapor permeabilities of polyethylene polyamide blends

Jinnah, Ishtiaq Ali. January 1983 (has links)
No description available.
4

Oxygen and water vapor permeabilities of polyethylene polyamide blends

Jinnah, Ishtiaq Ali. January 1983 (has links)
No description available.
5

A study of the water permeability of Portland cement concrete

Blackman, James Samuel January 2011 (has links)
Typescript, etc. / Digitized by Kansas State University Libraries
6

Analysis of moisture transfer in porous media : application to building materials

Saidani-Scott, Hind January 1993 (has links)
No description available.
7

The flow of liquid polymers through fibrous reinforcements

Griffin, Patrick Robert January 1995 (has links)
Resin Transfer Moulding (RTM), at present, is a semi-automated, low volume production process for fibre reinforced plastics with much work being undertaken to achieve full automation and medium volume production. The efficient and consistent impregnation of thermosetting resin into a reinforcement pack are key requirements in the development of R TM. For mass production and automation accurate predictions of mould fill times are critical in order to plan production. At present, the fill times are predicted by assuming Darcy's law and using experimentally determined permeability value. Permeability measurements display a large amount of scatter which affects the accuracy of simulations of mould filling. Commercial fabrics such as 'Injectex' are now available which achieve high permeability to resin flow through a modified microstructural architecture of fibre tows. This thesis seeks to examine the relationship between microstructure and permeability in these fabrics in the context of possible decreases in mechanical properties which may result from non-uniform fibre distribution. An image analysis technique is used to characterise and quantify the regions of flow within the fabric architecture which are then correlated with a series of permeability measurements determined experimentally. This then leads onto a mathematical model for the prediction of the permeability of the fibre pack.
8

The permeability hysterisis of Indiana limestone during isotropic compression /

Głowacki, Adrian. January 2006 (has links)
This thesis presents the evolution of intrinsic permeability of Indiana Limestone obtained from testing cylindrical samples subjected to isotropic confining pressure. The cylindrical samples measured 200 mm in height and 100 mm in diameter and were subjected to confining pressure ranging from 5 MPa to 60 MPa. The permeability was determined by subjecting the sample to a constant hydraulic gradient perpendicular to the bedding direction. Three different types of tests were performed: partial-loading and unloading in cycles to a the peak load of 60 MPa, monotonic loading to peak value of 60 MPa, followed by complete unloading to 5 MPa and reloading, monotonic loading to a confining pressure less than 60 MPa and unloading to the reference confining pressure of 5 MPa. It was observed that significant irreversible reductions in permeability took place. Three model curves are proposed to describe this permeability change for the loading, unloading and reloading paths. The results of the research indicate that only one data set from the third test was necessary to develop the model that accurately matched the second and third test.
9

Well-testing and characterisation of meandering fluvial channel reservoirs

Zheng, Shi-Yi January 1997 (has links)
No description available.
10

Permeability of cellophane to liquids and vapours

Archer, William Lucas January 1950 (has links)
To interpret the permeability phenomena which are exhibited by cellulose, a knowledge of its structure and certain physical properties is essential. Although the present study is concerned with cellophane, which is a regenerated form of cellulose, it is preferable first to consider these aspects in native cellulose, and subsequently to describe the changes which occur as a result of regeneration.

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