Fuel Injector: Air swirl characterization aerothermal modeling, phase 2, volume 2

A well integrated experimental/analytical investigation was conducted to provide benchmark quality data relevant to prefilming type airblast fuel nozzle and its interaction with combustor dome air swirler. The experimental investigation included a systematic study of both single-phase flows that involved single and twin co-axial jets with and without swirl. A two-component Phase Doppler Particle Analyzer (PDPA) equipment was used to document the interaction of single and co-axial air jets with glass beads that simulate nonevaporating spray and simultaneously avoid the complexities associated with fuel atomization processes and attendant issues about the specification of relevant boundary conditions. The interaction of jets with methanol spray produced by practical airblast nozzle was also documented in the spatial domain of practical interest. Model assessment activities included the use of three turbulence models (k-epsilon, algebraic second moment (ASM) and differential second moment (DSM)) for the carrier phase, deterministic or stochastic Lagrangian treatment of the dispersed phase, and advanced numerical schemes. Although qualitatively good comparison with data was obtained for most of the cases investigated, the model deficiencies in regard to modeled dissipation rate transport equation, single length scale, pressure-strain correlation, and other critical closure issues need to be resolved before one can achieve the degree of accuracy required to analytically design combustion systems

Fuel injector: Air swirl characterization aerothermal modeling, phase 2, volume 1

A well integrated experimental/analytical investigation was conducted to provide benchmark quality relevant to a prefilming type airblast fuel nozzle and its interaction with the combustor dome air swirler. The experimental investigation included a systematic study of both single-phase flows that involved single and twin co-axial jets with and without swirl. A two-component Phase Doppler Particle Analyzer (PDPA) was used to document the interaction of single and co-axial air jets with glass beads that simulate nonevaporating spray and simultaneously avoid the complexities associated with fuel atomization processes and attendant issues about the specification of relevant boundary conditions. The interaction of jets with methanol spray produced by practical airblast nozzle was also documented in the spatial domain of practical interest. Model assessment activities included the use of three turbulence models (k-epsilon, algebraic second moment (ASM), and differential second moment (DSM)) for the carrier phase, deterministic or stochastic Lagrangian treatment of the dispersed phase, and advanced numerical schemes. Although qualitatively good comparison with data was obtained for most of the cases investigated, the model deficiencies in regard to modeled dissipation rate transport equation, single length scale, pressure-strain correlation, and other critical closure issues need to be resolved before one can achieve the degree of accuracy required to analytically design combustion systems

Theoretical analysis of a novel integrated energy system formed by a microturbine and a exhaust fired single-double effect absorption chiller

Integrated Energy Systems (IES) combine a distributed power generation system (DG) such as a microturbine generator (MTG) or a fuel cell with thermally activated technologies (TAT) such as absorption cooling. This integration maximizes the efficiency of energy use by utilizing on-site most of the waste heat generated by DG, and reduces harmful emissions to the environment. This study investigates the energy and exergy performance of an IES. This system is comprised of an MTG with internal recuperator and a novel absorption cooling cycle. The absorption cycle is a single-double effect exhaust fired cycle, which recuperates the heat exchanged from the MTG exhaust gases using two generators at two different levels of temperature. The selection of the DG element, the TAT element and their internal configurations is based upon a real IES commercial unit that has been tested in the APEP-UCI DG testing facilities in Irvine, California. This unit has an electrical power capacity of 28 kW and a cooling capacity of 14 refrigeration tons (49.2 kW). Inputs for the thermodynamic models developed for the MTG and for the absorption cycle are derived from experimental variables that will be controlled in the testing phase. The MTG model is using empirical correlations for key model parameters (pressure ratio, turbine inlet temperature, etc.) from previous studies in order to predict the observed change in performance with part load operation. The calculated mass flow rate and temperature of the exhaust gases are inputs for the absorption cycle model, together with cooling and chilled water inlet temperatures and flow rates. Heat and mass transferefficiencies along with heat transfer coefficients for the suite of heat exchangers comprising the single-double effect absorption cycle are determined from proprietary testing data provided by the manufacturers

Biomass allocation response of sitanion hystrix to soil water stress

1986 Fall.Includes bibliographical references

We must become gatekeepers : editing indigenous writing

With the proliferation of Indigenous texts currently published by specialist and mainstream publishers, non-Indigenous editors increasingly find themselves negotiating the uncomfortable territories of race, politics and power for which current training (in an Australian context) leaves them poorly prepared. Indigenous writer Anita Heiss advocates the employment of Indigenous editors as an \u27ideal\u27 solution, though few are currently working in the Australian industry. Margaret McDonell, an experienced non-Indigenous editor of Indigenous texts, suggests non-Indigenous editors need to \u27undertake a journey of learning\u27 during which \u27assumptions, biases, tastes and preconceptions\u27 are examined. Yet this presents a difficult task within a postcolonial society, when, as identified by Clare Bradford, even the classification of texts into genres such as fiction and the short story represents an entirely Eurocentric construct, \u27not readily correspond[ing] with Aboriginal schemata\u27. The Australian Society of Authors\u27 discussion paper \u27Writing about Indigenous Australia: Some Issues to Consider and Protocols to Follow\u27 provides practical guidelines that may be adapted for editorial use. This article canvasses these and other ideas with a focus on establishing an ethical and appropriately sensitive cross-cultural approach to editing Indigenous writing.<br /

Non-Intrusive Measurement of Gaseous Species in Reacting and Non-Reacting Sprays

A non-intrusive technique for measuring the concentration of gaseous species in reacting and non-reacting sprays is presented. Infrared absorption is the basis for the measurement. In a two-phase situation, the light scattered by particles can be deduced by measuring extinction of wavelengths at which no absorption occurs. As a result, combined infrared extinction and scattering (IRES) is employed for two-phase flows. The technique, although based on line-of-sight absorption, has the potential to be spatially-resolved for either symmetric or asymmetric fields depending upon the deconvolution technique applied. The technique is demonstrated using a single phase methanol vapor/air free jet and non-reacting and reacting methanol sprays. To complement these results, measurements of droplet size and velocity as well as gas velocity can be achieved using other non-intrusive approaches such as phase Doppler interferometry. These complementary measurements may be combined with the concentration measurements to quantify vaporization. The results illustrate the applicability of this relatively inexpensive and simple technique which adds valuable information to the study of sprays. © 1991, Taylor &amp; Francis Group, LLC. All rights reserved

Novel Class 1 Integron Harboring Antibiotic Resistance Genes in Wastewater-Derived Bacteria as Revealed by Functional Metagenomics

Combatting antibiotic resistance is critical to our ability to treat infectious diseases. Here, we identified and characterized diverse antimicrobial resistance genes, including potentially mobile elements, from synthetic wastewater treatment microcosms exposed to the antibacterial agent triclosan. After seven weeks of exposure, the microcosms were subjected to functional metagenomic selection across 13 antimicrobials. This was achieved by cloning the combined genetic material from the microcosms, introducing this genetic library into E. coli, and selecting for clones that grew on media supplemented with one of the 13 antimicrobials. We recovered resistant clones capable of growth on media supplemented with a single antimicrobial, yielding 13 clones conferring resistance to at least one antimicrobial agent. Antibiotic susceptibility analysis revealed resistance ranging from 4 to \u3e50 fold more resistant, while one clone showed resistance to multiple antibiotics. Using both Sanger and SMRT sequencing, we identified the predicted active gene(s) on each clone. One clone that conferred resistance to tetracycline contained a gene encoding a novel tetA-type efflux pump that was named TetA(62). Three clones contained predicted active genes on class 1 integrons. One integron had a previously unreported genetic arrangement and was named In1875. This study demonstrated the diversity and potential for spread of resistance genes present in human-impacted environments