The Experts below are selected from a list of 17013 Experts worldwide ranked by ideXlab platform
Rongshun Wang - One of the best experts on this subject based on the ideXlab platform.
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Dynamic simulation of a single nitrogen expansion cycle for natural gas liquefaction under refrigerant Inventory Operation
Applied Thermal Engineering, 2018Co-Authors: Ying Zhan, Rongshun WangAbstract:Abstract Nitrogen (N2) expansion natural gas liquefaction technology is wildly used for liquefied natural gas production due to its unique advantages. However, few works have been reported about the detailed unit operating performance of N2 expansion system under refrigeration Inventory Operation that is one of the most effective Operations for adjusting system refrigeration capacity. In this study, we have comprehensively investigated the dynamic characteristics of a single N2 expander liquefier under Inventory Operation. Firstly, system model of the liquefier is developed based on rigorous first principles, valid empirical correlations and accurate physical property. Meanwhile, plate-fin heat exchanger model, as a key component, is reasonably and greatly simplified according to symmetric layer arrangements. Using the system model, the transient system behaviors are identified and evaluated. The primary performance parameters of centrifugal compressor train, e.g. efficiency, surge margin and input power, experience the most dramatic changes during the first several seconds after the Operation starts. ±6% variations in total nitrogen refrigerant mass result in −4.5 and +5.6 °C variations in LNG temperature, +8.7% and −8.4% variations in liquefier input power and maximum −7.8% variation in compressor surge margin, eventually. In general, the liquefier exhibits strong nonlinear behaviors.
G W Johnsen - One of the best experts on this subject based on the ideXlab platform.
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thermal hydraulic processes during reduced Inventory Operation with loss of residual heat removal
1992Co-Authors: S A Naff, G W Johnsen, D E Palmrose, E D Hughes, C M Kullberg, W C ArcieriAbstract:Nuclear power plant conditions during outages differ markedly from those prevailing at normal full-power Operation on which most past research has concentrated. This report identifies the topics needed to understand pressurized water reactor response to an extended loss-of-residual heat removal event during refueling and maintenance outages. By identifying the possible plant conditions and cooling methods that might be used, the controlling thermal-hydraulic processes and phenomena were identified. Gravity drain into the reactor coolant system, core water boil-off, and reflux condensation cooling were investigated in detail for example plants from each of the three US pressurized water reactor vendors. The reactor coolant system pressure that would result from reflux cooling was calculated under various assumed conditions and compared to threshold pressures for various temporary closures that might be in use. The viability of various potential gravity feed-and-bleed approaches also was studied.
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thermal hydraulic processes involved in loss of residual heat removal during reduced Inventory Operation
1991Co-Authors: C D Fletcher, S A Naff, P R Mchugh, G W JohnsenAbstract:This paper identifies the topics needed to understand pressurized water reactor response to an extended loss of residual heat removal event during refueling and maintenance outages. By identifying the possible plant conditions and cooling methods that would be used for each cooling mode, the controlling thermal-hydraulic processes and phenomena were identified. Controlling processes and phenomena include: gravity drain, core water boil-off, and reflux cooling processes. Important subcategories of the reflux cooling processes include: the initiation of reflux cooling from various plant conditions, the effects of air on reflux cooling, core level depression effects, issues regarding the steam generator secondaries, and the special case of boiler-condenser cooling with once-through steam generators. 25 refs., 6 figs., 1 tab.
Ying Zhan - One of the best experts on this subject based on the ideXlab platform.
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Dynamic simulation of a single nitrogen expansion cycle for natural gas liquefaction under refrigerant Inventory Operation
Applied Thermal Engineering, 2018Co-Authors: Ying Zhan, Rongshun WangAbstract:Abstract Nitrogen (N2) expansion natural gas liquefaction technology is wildly used for liquefied natural gas production due to its unique advantages. However, few works have been reported about the detailed unit operating performance of N2 expansion system under refrigeration Inventory Operation that is one of the most effective Operations for adjusting system refrigeration capacity. In this study, we have comprehensively investigated the dynamic characteristics of a single N2 expander liquefier under Inventory Operation. Firstly, system model of the liquefier is developed based on rigorous first principles, valid empirical correlations and accurate physical property. Meanwhile, plate-fin heat exchanger model, as a key component, is reasonably and greatly simplified according to symmetric layer arrangements. Using the system model, the transient system behaviors are identified and evaluated. The primary performance parameters of centrifugal compressor train, e.g. efficiency, surge margin and input power, experience the most dramatic changes during the first several seconds after the Operation starts. ±6% variations in total nitrogen refrigerant mass result in −4.5 and +5.6 °C variations in LNG temperature, +8.7% and −8.4% variations in liquefier input power and maximum −7.8% variation in compressor surge margin, eventually. In general, the liquefier exhibits strong nonlinear behaviors.
S A Naff - One of the best experts on this subject based on the ideXlab platform.
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thermal hydraulic processes during reduced Inventory Operation with loss of residual heat removal
1992Co-Authors: S A Naff, G W Johnsen, D E Palmrose, E D Hughes, C M Kullberg, W C ArcieriAbstract:Nuclear power plant conditions during outages differ markedly from those prevailing at normal full-power Operation on which most past research has concentrated. This report identifies the topics needed to understand pressurized water reactor response to an extended loss-of-residual heat removal event during refueling and maintenance outages. By identifying the possible plant conditions and cooling methods that might be used, the controlling thermal-hydraulic processes and phenomena were identified. Gravity drain into the reactor coolant system, core water boil-off, and reflux condensation cooling were investigated in detail for example plants from each of the three US pressurized water reactor vendors. The reactor coolant system pressure that would result from reflux cooling was calculated under various assumed conditions and compared to threshold pressures for various temporary closures that might be in use. The viability of various potential gravity feed-and-bleed approaches also was studied.
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thermal hydraulic processes involved in loss of residual heat removal during reduced Inventory Operation
1991Co-Authors: C D Fletcher, S A Naff, P R Mchugh, G W JohnsenAbstract:This paper identifies the topics needed to understand pressurized water reactor response to an extended loss of residual heat removal event during refueling and maintenance outages. By identifying the possible plant conditions and cooling methods that would be used for each cooling mode, the controlling thermal-hydraulic processes and phenomena were identified. Controlling processes and phenomena include: gravity drain, core water boil-off, and reflux cooling processes. Important subcategories of the reflux cooling processes include: the initiation of reflux cooling from various plant conditions, the effects of air on reflux cooling, core level depression effects, issues regarding the steam generator secondaries, and the special case of boiler-condenser cooling with once-through steam generators. 25 refs., 6 figs., 1 tab.
W C Arcieri - One of the best experts on this subject based on the ideXlab platform.
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thermal hydraulic processes during reduced Inventory Operation with loss of residual heat removal
1992Co-Authors: S A Naff, G W Johnsen, D E Palmrose, E D Hughes, C M Kullberg, W C ArcieriAbstract:Nuclear power plant conditions during outages differ markedly from those prevailing at normal full-power Operation on which most past research has concentrated. This report identifies the topics needed to understand pressurized water reactor response to an extended loss-of-residual heat removal event during refueling and maintenance outages. By identifying the possible plant conditions and cooling methods that might be used, the controlling thermal-hydraulic processes and phenomena were identified. Gravity drain into the reactor coolant system, core water boil-off, and reflux condensation cooling were investigated in detail for example plants from each of the three US pressurized water reactor vendors. The reactor coolant system pressure that would result from reflux cooling was calculated under various assumed conditions and compared to threshold pressures for various temporary closures that might be in use. The viability of various potential gravity feed-and-bleed approaches also was studied.
