The Experts below are selected from a list of 30810 Experts worldwide ranked by ideXlab platform
Georges Guiochon - One of the best experts on this subject based on the ideXlab platform.
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use of the isopycnic plots in designing operations of supercritical fluid chromatography v Pressure and density drops using mixtures of carbon dioxide and methanol as the mobile phase
Journal of Chromatography A, 2012Co-Authors: Abhijit Tarafder, Krzysztof Kaczmarski, Donald P Poe, Georges GuiochonAbstract:The drops of Pressure and density along chromatographic columns of different characteristics, eluted with different mixtures of carbon dioxide and methanol was mapped as functions of the column Outlet Pressure and the operating temperature. This paper extends an earlier report reporting the extent of the Pressure and density drops along chromatographic columns eluted with neat CO2 [1]. It illustrates the similarities and differences in the Pressure and density profiles along columns operated with mixed mobile phases and with neat CO2. Numerical calculations of the Pressure and density drops along columns packed with particles of different sizes, under different operating conditions (temperature, Outlet Pressure, and flow rate), provide important insights regarding the extent of the Pressure and density drops under these operating conditions.
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Pressure temperature and density drops along supercritical fluid chromatography columns i experimental results for neat carbon dioxide and columns packed with 3 and 5 micron particles
Journal of Chromatography A, 2012Co-Authors: Donald P Poe, Abhijit Tarafder, Krzysztof Kaczmarski, Georges Guiochon, Devon Veit, Megan RangerAbstract:Abstract The Pressure drop and temperature drop on columns packed with 3- and 5-micron particles were measured using neat CO2 at a flow rate of 5 mL/min, at temperatures from 20 °C to 100 °C, and Outlet Pressures from 80 to 300 bar. The density drop was calculated based on the temperature and Pressure at the column inlet and Outlet. The columns were suspended in a circulating air bath either bare or covered with foam insulation. The results show that the Pressure drop depends on the Outlet Pressure, the operating temperature, and the thermal environment. A temperature drop was observed for all conditions studied. The temperature drop was relatively small (less than 3 °C) for combinations of low temperature and high Pressure. Larger temperature drops and density drops occurred at higher temperatures and low to moderate Pressures. Covering the column with thermal insulation resulted in larger temperature drops and corresponding smaller density drops. At 20 °C the temperature drop was never more than a few degrees. The largest temperature drops occurred for both columns when insulated at 80 °C and 80 bar, reaching a maximum value of 21 °C for the 5-micron column, and 26 °C for the 3-micron column. For an adiabatic column, the temperature drop depends on the Pressure drop, the thermal expansion coefficient, and the density and the heat capacity of the mobile phase fluid, and can be described by a simple mathematical relationship. For a fixed operating temperature and Outlet Pressure, the temperature drop increases monotonically with the Pressure drop.
Kursad H Ersoy - One of the best experts on this subject based on the ideXlab platform.
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performance improvement of the vapour compression refrigeration cycle by a two phase constant area ejector
International Journal of Energy Research, 2009Co-Authors: Nagihan Bilir, Kursad H ErsoyAbstract:The performance of a vapour compression system that uses an ejector as an expansion device was investigated. In the analysis, a two-phase constant area ejector flow model was used. R134a was selected as the refrigerant. According to the obtained results, for any operating temperature there are different optimum values of Pressure drop in the suction chamber, ejector area ratio, ejector Outlet Pressure and cooling coefficient of performance (COP). As the difference between condenser and evaporator temperatures increases, the improvement ratio in COP rises whereas ejector area ratio drops. The minimum COP improvement ratio in the investigated field was 10.1%, while its maximum was 22.34%. Even in the case of an off-design operation, the performance of a system with ejector is higher than that of the basic system. Copyright © 2008 John Wiley & Sons, Ltd.
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performance improvement of the vapour compression refrigeration cycle by a two phase constant area ejector
International Journal of Energy Research, 2009Co-Authors: Nagihan Bilir, Kursad H ErsoyAbstract:The performance of a vapour compression system that uses an ejector as an expansion device was investigated. In the analysis, a two-phase constant area ejector flow model was used. R134a was selected as the refrigerant. According to the obtained results, for any operating temperature there are different optimum values of Pressure drop in the suction chamber, ejector area ratio, ejector Outlet Pressure and cooling coefficient of performance (COP). As the difference between condenser and evaporator temperatures increases, the improvement ratio in COP rises whereas ejector area ratio drops. The minimum COP improvement ratio in the investigated field was 10.1%, while its maximum was 22.34%. Even in the case of an off-design operation, the performance of a system with ejector is higher than that of the basic system. Copyright © 2008 John Wiley & Sons, Ltd.
Bengt Sundén - One of the best experts on this subject based on the ideXlab platform.
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the energy performance of a single screw compressor for natural gas liquefaction process effects of the lubricating oil flow rate
International Journal of Energy Research, 2019Co-Authors: Yong Li, Yuanwei Lu, Yuting Wu, Bengt SundénAbstract:An experimental test system including the oil circulation system and the gas circuit system has been designed and built to explore the effects of the lubricating oil flow rate on the performance of a single-screw compressor, used in a portable natural gas liquefaction process. Outlet Pressure, Outlet volumetric flow rate, volumetric efficiency, and specific power rate are the parameters for evaluation of the energy performance of the single-screw compressor. The experimental results indicate that the Outlet Pressure and Outlet volumetric flow rate can be effectively increased by increasing the flow rate of the lubricating oil at different rotational frequencies and that a certain amount of lubricant oil is helpful to improve the volumetric efficiency. In terms of the specific power rate, the optimum oil-gas ratios are 0.7%, 0.93%, and 1.79%, and the corresponding Outlet Pressures are 0.45, 0.45, and 0.48 MPa at the conditions of 50, 40, and 30 Hz, respectively. (Less)
Mohammad Behshad Shafii - One of the best experts on this subject based on the ideXlab platform.
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a hybrid molten carbonate fuel cell and parabolic trough solar collector combined heating and power plant with carbon dioxide capturing process
Energy Conversion and Management, 2019Co-Authors: Mohammad Marefati, Mehdi Mehrpooya, Mohammad Behshad ShafiiAbstract:Abstract In this paper, a combined heating and power plant consisting of molten carbonate fuel cell and parabolic trough solar collector with the carbon dioxide capturing process is investigated. Electrochemical model of the fuel cell and numerical modeling of the solar system is done using MATLAB software and thermodynamic model of the power plant is done by HYSYS software. In this plant, solar system is used as a heat exchanger with a capacity of 10.4 MW. The gas turbine and molten carbonate fuel cell are able to produce 640 MW and 81 MW of electrical power, respectively. The results show that, the electrical, overall and exergy efficiencies of the power plant are 37.68%, 71.29% and 45.13%, respectively. Also, total exergy destruction of the process and carbon capture ratio are 346029 kW and 91%, respectively. The impacts of other parameters such as fuel and oxidant flow rate, Outlet Pressure of the turbine, air compressor and control valves and capacity of the solar farm on the performance of the process are also investigated.
Nagihan Bilir - One of the best experts on this subject based on the ideXlab platform.
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performance improvement of the vapour compression refrigeration cycle by a two phase constant area ejector
International Journal of Energy Research, 2009Co-Authors: Nagihan Bilir, Kursad H ErsoyAbstract:The performance of a vapour compression system that uses an ejector as an expansion device was investigated. In the analysis, a two-phase constant area ejector flow model was used. R134a was selected as the refrigerant. According to the obtained results, for any operating temperature there are different optimum values of Pressure drop in the suction chamber, ejector area ratio, ejector Outlet Pressure and cooling coefficient of performance (COP). As the difference between condenser and evaporator temperatures increases, the improvement ratio in COP rises whereas ejector area ratio drops. The minimum COP improvement ratio in the investigated field was 10.1%, while its maximum was 22.34%. Even in the case of an off-design operation, the performance of a system with ejector is higher than that of the basic system. Copyright © 2008 John Wiley & Sons, Ltd.
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performance improvement of the vapour compression refrigeration cycle by a two phase constant area ejector
International Journal of Energy Research, 2009Co-Authors: Nagihan Bilir, Kursad H ErsoyAbstract:The performance of a vapour compression system that uses an ejector as an expansion device was investigated. In the analysis, a two-phase constant area ejector flow model was used. R134a was selected as the refrigerant. According to the obtained results, for any operating temperature there are different optimum values of Pressure drop in the suction chamber, ejector area ratio, ejector Outlet Pressure and cooling coefficient of performance (COP). As the difference between condenser and evaporator temperatures increases, the improvement ratio in COP rises whereas ejector area ratio drops. The minimum COP improvement ratio in the investigated field was 10.1%, while its maximum was 22.34%. Even in the case of an off-design operation, the performance of a system with ejector is higher than that of the basic system. Copyright © 2008 John Wiley & Sons, Ltd.
