Global ETD Search
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Showing 1 to 20 of 23 for “"tracer gas"”.
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INVESTIGATION OF TRACER GAS VARIABILITY FROM OBSERVATIONS AND MODELS
The variability of the tracer gases CO2 and ozone was investigated utilizing in-situ measurements, satellite retrievals, and model simulations. In the tropical region, using Atmospheric Infrared Sounder (AIRS) mid-tropospheric CO2 retrievals led to the discovery of a signal with a periodicity of …
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Detection of secondary flow in a turbine cascade using a tracer gas technique
… cascade. Fluid motion was determined using a tracer gas technique. Ethylene was injected into the pressure-side and suction-side legs of the horseshoe vortex, near the leading edge of the cascade. Ethylene concentrations were determined at two downstream locations using a flame ionization …
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Development of a remote analysis method for underground ventilation systems using tracer gas and CFD
… This study developed a methodology that uses tracer gas techniques and CFD modeling to analyze underground mine ventilation system status remotely. After an unanticipated event that has damaged ventilation controls, the first step of the methodology is to assess and estimate the level of the …
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Characterizing the dynamics of a multizone enclosure by identifying unknown system parameters using tracer gas techniques and least squares identification algorithms
Restriction data tranferred 2014-07-01T11:25:32-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: ETDs are only available to UIUC Users without author permission
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Development and Evaluation of a Permeation Plug Release Vessel (PPRV) for the Release of Perfluoromethylcyclohexane (PMCH) in Underground Mine Tracer Gas Studies
The use of sulfur hexafluoride (SF6) as a tracer gas for analyzing underground mine ventilation systems has been practiced for over 30 years. As a result, the methods used to release, sample, and analyze SF6 are well accepted. Although improvements are still being made to enhance the analysis of …
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Determination of a novel mine tracer gas and development of a methodology for sampling and analysis of multiple mine tracer gases for characterization of ventilation systems
… rescue personnel into the mine. By utilizing tracer gas techniques, which are powerful techniques for monitoring ventilation systems, especially in remote or inaccessible areas, analysis of the ventilation system immediately following a mine emergency can be more rapidly ascertained. However, …
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A detailed justification for the selection of a novel mine tracer gas and development of protocols for GC-ECD analysis of SPME sampling in static and turbulent conditions for assessment of underground mine ventilation systems
Tracer gas surveys are a powerful means of assessing air quantity in underground mine ventilation circuits. The execution of a tracer gas style ventilation survey allows for the direct measurement of air quantity in locations where this information is otherwise unattainable. Such instances include …
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Approaches to Simulation of an Underground Longwall Mine and Implications for Ventilation System Analysis
… longwall mine, especially for the use of tracer gas in an emergency situation. In an emergency situation, limited information about the state of mine ventilation system is known, and it is difficult to make informed decisions about safety of the mine for rescue personnel. With careful …
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Design of an Experimental Mine Simulator for the Development of a Procedure for Utilization Multiple Tracer Gases in Underground Mines
… was constructed which will be used to conduct tracer gas experiments in the laboratory. The test apparatus simulates a mine in a tabular deposit and is modular and simple and can be easily rearranged to represent a variety of mine geometries. The apparatus is appropriate for the use of tracer …
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Nitrous oxide as a substitute for sulfur hexafluoride in the ANSI/ASHRAE 110 Method of hood performance evaluation
… Sulfur hexafluoride is specified as the gas most suitable for this test and is most commonly used. Sulfur hexafluoride use has potential negative environmental repercussions as it is a potent greenhouse gas with a global warming potential 22,800 times greater per mass than CO₂. The …
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A NOVEL APPROACH TO NEAR-REAL TIME MONITORING OF VENTILATION RATE AND INDOOR AIR QUALITY IN RESIDENTIAL HOUSES
… a physics-based infiltration model with a tracer gas decay test method. The methodology is applicable to naturally ventilated houses. Existing infiltration models are modified explicitly to include the impact of the wind direction. The input data for the model also include indoor air …
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Masonry heater performance evaluation: efficiency, emissions, and thermal modeling
… the chemical energy loss and the dry stack gas mass for calculation of sensible energy loss. The sensible loss that occurs during the off-period, when combustion of wood has stopped, is measured directly by injecting carbon dioxide in the stack and using it as a tracer gas to measure stack …
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Comparison of concentrations in the breathing zone
… Ethanol vapor mixed with nitrogen was used as a tracer gas. Samples were taken at the forehead, adjacent to the nose (nose), the mouth, neck, chest, right lapel, left lapel. Nose was sampled at l liter per minute (lpm) and 0.15 lpm at different times, while the others were sampled at 0.15 lpm at …
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Indoor Air Monitoring of Ethanol and Benzene in a Pilot Winery Using Active Sampling
… content testing and storage/finishing.</p> <p>Tracer gas decay air exchange tests were conducted to determine the air exchange rate of the winery workroom. A single-space mass-balance model was used to estimate the air exchange rate for the entire workroom. The calculated air exchange rates …
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Air Pollution Distribution under an Elevated Train Station (A Case Study of Silom Station in Downtown Bangkok)
… dispersion in the train station area. A tracer gas (CO₂) was emitted from a simulated line source with emission rates of 0.383, 0.681, 1.293, 2.586, 5.177 and 10.77 mg/min to simulate actual pollutant emission rates. The CO₂ gas was sampled at 55 locations in the model. The Kriging method …
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Experimental investigation of local air-side heat transfer coefficients of heat exchanger fins via an absorption-based mass transfer method
… on the interaction of a coating material and a tracer gas. Upon absorption of the tracer gas, the acidic coating layer reacts with a color change. Based on the rate of the observed color change, the local mass transfer can be quantified on the surface of interest. The thin and uniform coating …
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Flow characteristics of jet fans in mines: experimental and numerical modeling
… the opposite wall. Carbon dioxide was used as a tracer gas to measure the effective ventilating air quantity near the face and re-circulation in various tests. The re-circulation involved in the system was found to be less than 40% in all the experiments. It was also found that the use of line …
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Development of Potential Remote Coal Mine Fire Response Measures: Use of Multiple Passive Source Tracers and Simulation of High Expansion Foam Flow in Simulated Gob Material
… fire. The application of multiple passive source tracers provides improved detail of complex ventilation interactions over an extended period of time. The first work in this thesis details the testing of the passive release rates for three Perfluorocarbon tracer compounds over a 180-day period. …
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Evaluation of displacement ventilation for use in high-ceiling facilities
… by use of strategically placed temperature, tracer gas, and velocity measurements. The modeled loads consisted of traditional person, computer, and lighting loads found in offices as well as simulators constructed to represent generic welding, engine exhaust and control panel enclosures in a …
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Quality assurance project plan for a ruminant emission measurement system
… to atmospheric accumulation of greenhouses gases. A Ruminant Emission Measurement System (REMS) was designed, constructed and tested at the Metabolism Unit of the Beef Cattle and Sheep Field Laboratory at the University of Illinois at Urbana-Champaign to quantify these emission rates for …
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