On the design of software and hardware for a WSN transmitter

Software defined radios (SDR) are booming. However, for a final breakthrough these systems need to be versatile, inexpensive and easy to program. In this paper a next step is taken to meet all these requirements. Our hardware consists of a computer with an affordable data acquisition (DAQ) card and a cheap self-made single-stage up-converter. The software is written in the slow learning-curve graphical programming environment LabVIEW. To prove the versatility of our SDR transmitter concept, we send packets with the wireless sensor networks (WSN) protocol IEEE 802.15.4, which are received by an existing packet sniffer

Upscaling Polymer Flooding in Heterogeneous Reservoirs

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Adsorption of pentachlorophenol onto activated carbon in a fixed bed : a thesis presented in partial fulfilment of the requirements for the degree of Master of Technology in Environmental Engineering at Massey University

The adsorption of pentachlorophenol (PCP) from water onto granular activated carbon (GAC) was studied. Equilibrium and kinetic behaviour was studied, and the results used to predict fixed bed adsorber behaviour. Batch equilibrium tests showed that the adsorption capacity of activated carbon for PCP is best represented by the Freundlich isotherm, with constants of K = 95 and 1/n = 0.18. Batch adsorption kinetics experiments were conducted in a spinning basket reactor. Surface diffusion and external film transfer coefficients were determined by fitting the homogeneous surface diffusion model (HSDM) to the experimental batch adsorption data. A surface diffusion coefficient value of 2.26 x 10-9cm/s was calculated using this method, which was similar to surface diffusion coefficients for similar compounds found by other investigators. Using equilibrium and kinetic parameters, the HSDM was used to predict bench scale fixed bed adsorber breakthrough curves at varying flow rates. A correlation was used to calculate the film transfer coefficient. There was a good agreement between the experimental breakthrough curves and those predicted by the model. By varying parameters in the model it was found that the adsorption rate in the PCP-activated carbon system was primarily limited by surface diffusion. The homogeneous surface diffusion model was shown to be effective in predicting breakthrough of PCP and could conceivably be used to predict full scale adsorber performance or to aid pilot plant studies

From invasion percolation to flow in rock fracture networks

The main purpose of this work is to simulate two-phase flow in the form of immiscible displacement through anisotropic, three-dimensional (3D) discrete fracture networks (DFN). The considered DFNs are artificially generated, based on a general distribution function or are conditioned on measured data from deep geological investigations. We introduce several modifications to the invasion percolation (MIP) to incorporate fracture inclinations, intersection lines, as well as the hydraulic path length inside the fractures. Additionally a trapping algorithm is implemented that forbids any advance of the invading fluid into a region, where the defending fluid is completely encircled by the invader and has no escape route. We study invasion, saturation, and flow through artificial fracture networks, with varying anisotropy and size and finally compare our findings to well studied, conditioned fracture networks.Comment: 18 pages, 10 figure

On the understanding and feasibility of “Breakthrough” Osmosis

Osmosis is the movement of solvent across a permselective membrane induced by a solute-concentration gradient. Now in ‘Forward Osmosis’ it is empirically observed that the diffusion of the solute is counter to that of the solvent i.e. there is so-called “reverse salt diffusion”. However it has been recently suggested, in a theoretical paper, that if allowance is made for minor deviations from ideal semi-permeability then operation in an overlooked mode of “breakthrough” osmosis would be possible and importantly it would yield relatively large rates of osmosis. A consequential prediction was that in “breakthrough mode”, Pressure-Retarded Osmosis (PRO) would generate very high power densities exceeding those in the conventional mode by one order of magnitude. The practicality of this suggestion was explored and necessarily questions were then raised regarding the foundation of the Spiegler-Kedem-Katchalsky model

Evaluation of CO2 and Carbonated Water EOR for Chalk Fields

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Evolution of drainage system morphology at a land-terminating Greenland outlet glacier

This work was funded by the UK Natural Environment Research Council (through grants to Nienow, Mair, and Wadham, and a studentship to Bartholomew), the Edinburgh University Moss Centenary Scholarship (Cowton and Bartholomew), and a Carnegie Research Grant (Nienow). We thank Ian Willis, Tim Bartholomaus and an anonymous referee for valuable comments which significantly improved the manuscript.Peer reviewedPublisher PD

Impact of Flow Rate and Wettability on the Determination of Relative Permeability from Core Floods

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