Low differential pressure and multiphase flow measurements by means of differential pressure devices

The response of slotted plate, Venturi meter and standard orifice to the presence of two phase, three phase and low differential flows was investigated. Two mixtures (air-water and air-oil) were used in the two-phase analysis while a mixture of air, water and oil was employed in the three-phase case. Due to the high gas void fraction (α>0.9), the mixture was considered wet gas. A slotted plate was utilized in the low differential pressure analysis and the discharge coefficient behavior was analyzed. Assuming homogeneous flow, an equation with two unknowns was obtained for the multi-phase flow analysis. An empirical relation and the differential response of the meters were used to estimate the variables involved in the equation. Good performance in the gas mass flow rate estimation was exhibited by the slotted and standard plates for the air-water flow, while poor results were obtained for the air-oil and air-water oil flows. The performance of all the flow meter tested in the analysis improved for differential pressures greater than 24.9 kPa (100 in_H2O). Due to the tendency to a zero value for the liquid flow, the error of the estimation reached values of more than 500% at high qualities and low differential pressures. Air-oil and air-water-oil flows show that liquid viscosity influences the response of the differential pressure meters. The best results for high liquid viscosity were obtained in the Venturi meter using the recovery pressure for the gas flow estimation at differential pressures greater than 24.9 kPa (100 in_H2O). A constant coefficient Cd was used for the low differential pressure analysis and results did show that for differential pressure less than 1.24 kPa (5 inH2O) density changes are less than 1% making possible the incompressible flow assumption. The average of the computed coefficients is the value of Cd

Advanced Gas Turbine (AGT) powertrain system development for automotive applications

Topics covered include the AGT 101 engine test; compressor design modification; cold air turbine testing; Mod 1 alloy turbine rotor fabrication; combustion aspects; regenerator development; and thermal screening tests for ceramic materials. The foil gas bearings, rotor dynamics, and AGT controls and accessories are also considered

Data Analysis and Correlations for the Particulate Matter Continuous Emission Monitoring System Test Program at the TSCA Incinerator

A field study was conducted to evaluate the performance of three commercially available particulate matter (PM) continuous emission monitoring systems (CEMS) during 1999-2000 at the U.S. Department of Energy (DOE) Toxic Substance Control Act (TSCA) Incinerator located near Oak Ridge, Tennessee. The incinerator is permitted to treat mixed-waste, Resource Conservation Recovery Act (RCRA) hazardous and nonhazardous waste, and wastes containing polychlorinated biphenyls (PCB). The mixed-waste treated at the incinerator contains both low-level radioactive and hazardous chemical constituents. The air pollution control system of the incinerator utilizes Maximum Achievable Control Technology (MACT), which is comprised of a rapid quench, venturi scrubber, packed bed scrubber, and two ionizing wet scrubbers in series. The CEMS chosen for the demonstration were two beta-gauge devices and a light-scattering device. The performance of the CEMS was evaluated using the requirements in the Environmental Protection Agency (EPA) draft (11-3-98) Performance Specification 11 (PS11) and draft (11-3-98) Procedure 2. The various possible combinations of treating liquid, aqueous, and solid wastes simultaneously presented a challenge in establishing a single, acceptable correlation relationship for the individual CEMS. The flue gas of the incinerator was also continually at or near saturated moisture conditions, yet offering an additional challenge to the CEMS. The results of the EPA reference Method 5i stack tests for establishing the calibration .curves demonstrated that the beta-gauge monitors could meet PS11 criteria, and the light-scattering monitor could not meet PS11 criteria. Experience seemed to establish however, that more than one set of correlation tests might be necessary to determine the nature of the calibration curve

Air pollution monitoring instrumentation A survey

Air pollution monitoring instrumentation developed for aerospace uses surveyed for industrial application