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Numerical Study On The Dynamic Process Of Single Plume Flow In Thermal Convection With Polymers, Jian-Ping Cheng, Wei-Hua Cai, Hong-Na Zhang, Feng-Chen Li, Lian Shen, Shi-Zhi Qian

Mechanical & Aerospace Engineering Faculty Publications

A direct numerical simulation of single plume flow in thermal convection with polymers was carried out in a domain with 1:3 as the width to height ratio. The heat transport ability is weakened by adding polymers within the here-investigated governing parameter range. However, it is promoted when the maximum polymer extension L is increased. The distribution of vertical velocity and temperature indicates that the plume in the polymer solution case is speeded up and widens bigger as compared to that in the Newtonian fluid case. Inside the plume, polymer chains tend to release energy at the position where the …

A Detailed Kinematic Map Of Cassiopeia A'S Optical Main Shell And Outer High-Velocity Ejecta, Dan Milisavljevic, Robert A. Fesen

Dartmouth Scholarship

We present three-dimensional (3D) kinematic reconstructions of optically emitting material in the young Galactic supernova remnant Cassiopeia A (Cas A). These Doppler maps have the highest spectral and spatial resolutions of any previous survey of Cas A and represent the most complete catalog of its optically emitting material to date. We confirm that the bulk of Cas A’s optically bright ejecta populate a torus-like geometry tilted approximately 30◦ with respect to the plane of the sky with a − 4000 to +6000 km s−1 radial velocity asymmetry. Near-tangent viewing angle effects and an inhomogeneous surrounding circumstellar material/ interstellar medium environment …

Measurements Of Co, Hcn, And C2h6 Total Columns In Smoke Plumes Transported From The 2010 Russian Boreal Forest Fires To The Canadian High Arctic, C Viatte, K Strong, C Paton-Walsh, J Mendonca, N T. O'Neill, J R. Drummond

Faculty of Science, Medicine and Health - Papers: part A

In August 2010, simultaneous enhancements of aerosol optical depth and total columns of carbon monoxide (CO), hydrogen cyanide (HCN), and ethane (C2H6) were observed at the Polar Environment Atmospheric Research Laboratory (PEARL, 80.05°N, −86.42°W, 0.61 km above sea level, Eureka, Nunavut, Canada). Moderate Resolution Imaging Spectroradiometer (MODIS) hot spots, Ozone Monitoring Instrument (OMI) aerosol index maps, and Hybrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) back-trajectories were used to attribute these enhancements to an intense boreal fire event occurring in Russia. A ground-based Fourier Transform InfraRed (FTIR) spectrometer at PEARL provided vertically integrated measurements of trace gases transported in smoke plumes. …

Measurements Of Reactive Trace Gases And Variable O3 Formation Rates In Some South Carolina Biomass Burning Plumes, S K. Akagi, Robert J. Yokelson, I R. Burling, S Meinardi, I Simpson, D R. Blake, G R. Mcmeeking, A Sullivan, T Lee, S Kreidenweis, S Urbanski, J Reardon, D W.T Griffith, T J. Johnson, D R. Weise

Faculty of Science, Medicine and Health - Papers: part A

In October–November 2011 we measured trace gas emission factors from seven prescribed fires in South Carolina (SC), US, using two Fourier transform infrared spectrometer (FTIR) systems and whole air sampling (WAS) into canisters followed by gas-chromatographic analysis. A total of 97 trace gas species were quantified from both airborne and ground-based sampling platforms, making this one of the most detailed field studies of fire emissions to date. The measurements include the first emission factors for a suite of monoterpenes produced by heating vegetative fuels during field fires. The first quantitative FTIR observations of limonene in smoke are reported along with …

Formaldehyde And Nitrogen Dioxide In Smoke Plumes From Australia's Black Saturday Fires, Emma Young, Clare Paton-Walsh

Faculty of Science - Papers (Archive)

The ‘Black Saturday’ fires were a series of devastating bushfires that burned across Victoria, Australia, during February 2009. The smoke plume from Saturday the 7th February, the worst day of the fires, separated from subsequent emissions and persisted for several weeks, providing the opportunity to track the changing composition of the smoke plume as it aged. In this study we have used satellite data from the Ozone Monitoring Instrument (OMI) and the Atmospheric InfraRed Sounder (AIRS) to characterise the emissions of formaldehyde and nitrogen dioxide from the fires. Emission ratios with respect to carbon monoxide are determined for formaldehyde (0.017 …

Exploring Co Pollution Episodes Observed At Rishiri Island By Chemical Weather Simulations And Airs Satellite Measurements: Long-Range Transport Of Burning Plumes And Implications For Emissions Inventories, Hiroshi Tanimoto, Keiichi Sato, Tim Butler, Mark G. Lawrence, Jenny A. Fisher, M Kopacz, Robert M. Yantosca, Yugo Kanaya, Shungo Kato, Tomoaki Okuda, Shigeru Tanaka, Jiye Zeng

Faculty of Science - Papers (Archive)

The summer of 2003 was an active forest fire season in Siberia. Several events of elevated carbon monoxide (CO) were observed at Rishiri Island in northern Japan during an intensive field campaign in September 2003. A simulation with a global chemistry-transport model is able to reproduce the general features of the baseline levels and variability in the observed CO, and a source attribution for CO in the model suggests that the contribution from North Asia dominated, accounting for approximately 50% on average, with contributions of 7% from North America and 8% from Europe and 30% from oxidation of hydrocarbons. With …

Time-Of-Flight Emission Profiles Of The Entire Plume Using Fast Imaging During Pulsed Laser Deposition Of Yba2Cu3O7−X, Carl J. Druffner, Glen P. Perram, Rand R. Biggers

Faculty Publications

Emission time-of-flight (TOF) profiles have been obtained using gated imagery to further the process control during the pulsed laser deposition of the high temperature superconductor, YBa₂Cu₃O_7−x⁠. An intensified charge coupled device array was used to obtain a sequence of plume images at 10ns temporal resolution and 0.2mm spatial resolution. Plume imagery is transformed to TOF profiles and pulse-to-pulse variations removed using physically based smoothing techniques. Comparison with non-imaging sensors establishes excellent agreement, with systematic uncertainties in streaming speed and temperatures of less than 15% and 8%, respectively. The resulting streaming speeds of 0.4–1.2×10 …

The Invariant Algorithm For Identification And Detection Of Multiple Gas Plumes And Weak Releases, Erin O'Donnell, David W. Messinger, Carl Salvaggio, John Schott

Articles

The ability to detect and identify gaseous effluents is a problem that has been pursued with limited success. It has been shown to bepossible using the Invariant algorithm on synthetic hyperspectralscenes with a strong single gas release. That however, is a veryspecific case and leaves room for further investigation. This studylooks at more realistic detection and release scenarios. Ourimplementation of the Invariant algorithm uses Singular ValueDecomposition (SVD) to select basis vectors from a subspace of targetgases in conjunction with a Generalized Likelihood Ratio Test (GLRT) to determine on a pixel by pixel basis how ``like" the target gas each pixel …

Identification And Detection Of Gaseous Effluents From Hyperspectral Imagery Using Invariant Algorithms, Erin M. O'Donnell, David W. Messinger, Carl Salvaggio, John Schott

Articles

The ability to detect and identify effluent gases is, and will continue to be, of great importance. This would not only aid in the regulation of pollutants but also in treaty enforcement and monitoring the production of weapons. Considering these applications, finding a way to remotely investigate a gaseous emission is highly desirable. This research utilizes hyperspectral imagery in the infrared region of the electromagnetic spectrum to evaluate an invariant method of detecting and identifying gases within a scene. The image is evaluated on a pixel-by-pixel basis and is studied at the subpixel level. A library of target gas spectra …

Visual Plumes Mixing Zone Modeling Software, Walter E. Frick

United States Environmental Protection Agency: Publications

The US Environmental Protection Agency has a history of developing plume models and providing technical assistance. The Visual Plumes model (VP) is a recent addition to the public-domain models available on the EPA Center for Exposure Assessment Modeling (CEAM) web page. The Windows-based VP adapts, modifies, and enhances the earlier DOS-based PLUMES with a new interface, models, and capabilities. VP is a public platform for mixing zone models designed to encourage the continued improvement of plume theory and models by facilitating verification and inter-model comparison. Some examples are presented to illustrate VP’s new capabilities. One demonstrates its ability, for reasonably …

The Importance Of Background In The Detection And Identification Of Gas Plumes Using Emissive Infrared Hyperspectral Sensing, Herbert Mitchell, Gerard P. Jellison, David P. Miller, Carl Salvaggio, Craig J. Miller

Articles

Using a Fourier transform infrared field spectrometer, spectral infrared radiance measurements were made of several generated gas plumes against both a uniform sky and terrestrial background. Background temperature, spectral complexity, and physical homogeneity each influenced the success of emissive infrared spectral sensing technology in detecting and identifying the presence of a gas plume and its component constituents. As expected, high temperature contrast and uniform backgrounds provided the best conditions for detectability and diagnostic identification. This report will summarize some of SITAC’s findings concerning plume detectability, including the importance of plume cooling, plumes in emission and absorption, the effects of optical …

Particle Growth In Urban And Industrial Plumes In Texas, Charles A. Brock, Michael Trainer, Thomas B. Ryerson, J. Andrew Neuman, David D. Parrish, John S. Holloway, Dennis K. Nicks, Gregory J. Frost, Gerhard Hübler, Fred C. Fehsenfeld, J. Charles Wilson, J. Michael Reeves, Bernard G. Lafleur, Henrike Hilbert, Elliot L. Atlas, Stephen G. Donnelly Ph.D., Sue M. Schauffler, Verity R. Stroud, Christine Wiedinmyer

Chemistry Faculty Publications

Particle size distributions and gas-phase particle precursors and tracer species were measured aboard an aircraft in the plumes downwind from industrial and urban sources in the vicinity of Houston, TX during the daytime in late August and early September 2000. Plumes originating from the Parish gas-fired and coal-fired power plant, petrochemical industries along the Houston ship channel, the petrochemical facilities near the Gulf coast, and the urban center of Houston were studied. Most of the particle mass flux advected downwind of Houston came from the industries and electrical utilities at the periphery of the city rather than from sources in …

Theoretical And Experimental Investigation Of Plumes From A Circular Distributed Source, Apichart Chaengbamrung, Paul Cooper, Peter W. Wypych, Ajit R. Godbole

Faculty of Engineering - Papers (Archive)

This paper describes work in the first part of an ongoing research programme on the generation and dispersion of fume from ' hot metal processes, a challenging industrial ventilation problem. '"This phase of the study involves research into a salt solution plume generated from an area source and descending into quiescent water. This is a 'cold flow' analogue of a thermal lume ascending in quiescent air. Expenments are described whereby the velocity and concentration profiles in the plume are determined using video footage and particle-tracking software, and a conductivity probe with digital traversing mechanism, respectively. Results from a transient numerical …

Theoretical And Experimental Investigation Of Descending Salt Plumes From A Circular Source, Apichart Chaengbamrung, Paul Cooper, Peter W. Wypych, Ajit R. Godbole

Faculty of Engineering and Information Sciences - Papers: Part A

This paper describes work in the first part of an ongoing research programme on the generation and dispersion of fume from hot metal processes, a challenging industrial ventilation problem. This phase of the study involves research into a salt solution plume generated from an area source and descending into quiescent water. This is a 'cold flow' analogue of a thermal plume ascending in quiescent air. Experiments are described whereby the velocity and concentration profiles in the plume are determined using video footage and particle-tracking software, and a conductivity probe with digital traversing mechanism, respectively. Results from a transient numerical simulation …

Modification Of Flow Model And Optimal Pumping Strategies For Capturing Tce And Dce Plumes Near Mission Drive, Wurtsmith Air Force Base, Michigan: Feasibility Study, Alaa H. Aly, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

Utah State University (USU) and Parsons Engineering Science (PES) were tasked by the Air Force Center for Environmental Excellence to:

( 1) Modify the three-dimensional basewide ground-water flow model for Wurtsmith Air Force Base (WAFS), Michigan (PES, 1997) based on recent investigation by ICF Kaiser (ICF).

(2) Develop contaminant transport models for OT-24 area TCE and DCE plumes. These models will use the same parameters that were used by ICF in their feasibility study ..

(3) Use the flow and transport models to develop optimal pumping strategies to achieve cleanup and capture of the plumes

Toward A Balanced Strategy To Address Contaminated Groundwater Plumes At The Massachusetts Military Reservation, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

This document contains the findings and recommendations of the Technical Review and Evaluation Team (TRET) for the plume containment project at the Massachusetts Military Reservation (MMR). The findings and recommendations are in response to the 60 Percent Plume Containment Design, submitted by Operational Technologies (OpTech) in January 1996. In short, the TRET recommends the MMR depart substantially from the strategy of simultaneous, 100 percent containment and treatment that was assigned to OpTech for design in accordance with the Record of Decision (ROD) for Interim Action. This strategy guided the course of the plume containment project over the past two years

Biological Removal Of Fine-Grained Lithogenic Particles From A Large River Plume, M. J. Dagg, E. P. Green, B. A. Mckee, P. B. Ortner

Journal of Marine Research

The pelagic tunicate, Oikopleura dioica, feeds by non-selectively filtering particles in the size range of 0.2–20 μm. In the northern Gulf of Mexico, particulate matter in this size range contains large amounts of fine-grained lithogenic material because of the influence of the Mississippi River. During May 1992, O. dioica populations filtered between 2 and 44% (mean = 20%) of the upper 5 m each day. The filtered lithogenic particles either remain in the oikopleurid house or are defecated in fecal pellets which have high sinking velocities. Either way, the larvacean populations significantly alter the fates of fine-grained lithogenic particles …

The Growth Of Convective Plumes At Seafloor Hot Springs, Kevin G. Speer, John Marshall

Journal of Marine Research

The growth of buoyant plumes in the presence of stratification (N) and rotation (f) is studied and illustrated with a number of numerical experiments of convection induced by a localized source of buoyancy at the lower boundary of a linearly stratified fluid. The presence of stratification constrains the convection in the vertical giving rise to an equilibrium-spreading layer which receives the rising mass of plume fluid; the plume can be divided into an upper, mass-source driven anticyclone and a lower, buoyancy-source (F) driven cyclone. With N/f large, the plume's rise-height is set by the …