The Experts below are selected from a list of 324 Experts worldwide ranked by ideXlab platform
Hongfei Zheng - One of the best experts on this subject based on the ideXlab platform.
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Comparative analysis of regenerative and Air-Extraction multi-stage humidification–dehumidification desalination system using pinch technology
Desalination, 2016Co-Authors: Huifang Kang, Teng Wang, Hongfei ZhengAbstract:Abstract To reduce energy consumption, the multi-stage type is a promising technology used in the humidification–dehumidification desalination system. Two types of multi-stage desalination system (regenerative and Air-Extraction multi-stage desalination) were proposed, and were studied and improved relatively separately. So, this paper comparatively investigated the two typical desalination systems based on the pinch technology. The pinch analysis models of regenerative and Air-Extraction multi-stage desalination were established and numerically analyzed. Subsequently, the effects of the pinch point temperature difference and the number of stage on the performance of the two desalination systems were comparatively analyzed. The result showed that the Gained Output Ratio (GOR) of regenerative multi-stage desalination was worse than that of Air-Extraction multi-stage desalination, while the Recovery Ratio (RR) of regenerative multi-stage desalination was better. Furthermore, when the single-stage system upgraded to two-stage system, the performance was significantly improved. But as the number of stage increases further, the enhancement effect is gradually weakened and even the performance becomes worse. The research content of this paper will help to select the device in the design of the desalination system.
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comparative analysis of regenerative and Air Extraction multi stage humidification dehumidification desalination system using pinch technology
Desalination, 2016Co-Authors: Huifang Kang, Teng Wang, Hongfei ZhengAbstract:Abstract To reduce energy consumption, the multi-stage type is a promising technology used in the humidification–dehumidification desalination system. Two types of multi-stage desalination system (regenerative and Air-Extraction multi-stage desalination) were proposed, and were studied and improved relatively separately. So, this paper comparatively investigated the two typical desalination systems based on the pinch technology. The pinch analysis models of regenerative and Air-Extraction multi-stage desalination were established and numerically analyzed. Subsequently, the effects of the pinch point temperature difference and the number of stage on the performance of the two desalination systems were comparatively analyzed. The result showed that the Gained Output Ratio (GOR) of regenerative multi-stage desalination was worse than that of Air-Extraction multi-stage desalination, while the Recovery Ratio (RR) of regenerative multi-stage desalination was better. Furthermore, when the single-stage system upgraded to two-stage system, the performance was significantly improved. But as the number of stage increases further, the enhancement effect is gradually weakened and even the performance becomes worse. The research content of this paper will help to select the device in the design of the desalination system.
Huifang Kang - One of the best experts on this subject based on the ideXlab platform.
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Comparative analysis of regenerative and Air-Extraction multi-stage humidification–dehumidification desalination system using pinch technology
Desalination, 2016Co-Authors: Huifang Kang, Teng Wang, Hongfei ZhengAbstract:Abstract To reduce energy consumption, the multi-stage type is a promising technology used in the humidification–dehumidification desalination system. Two types of multi-stage desalination system (regenerative and Air-Extraction multi-stage desalination) were proposed, and were studied and improved relatively separately. So, this paper comparatively investigated the two typical desalination systems based on the pinch technology. The pinch analysis models of regenerative and Air-Extraction multi-stage desalination were established and numerically analyzed. Subsequently, the effects of the pinch point temperature difference and the number of stage on the performance of the two desalination systems were comparatively analyzed. The result showed that the Gained Output Ratio (GOR) of regenerative multi-stage desalination was worse than that of Air-Extraction multi-stage desalination, while the Recovery Ratio (RR) of regenerative multi-stage desalination was better. Furthermore, when the single-stage system upgraded to two-stage system, the performance was significantly improved. But as the number of stage increases further, the enhancement effect is gradually weakened and even the performance becomes worse. The research content of this paper will help to select the device in the design of the desalination system.
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comparative analysis of regenerative and Air Extraction multi stage humidification dehumidification desalination system using pinch technology
Desalination, 2016Co-Authors: Huifang Kang, Teng Wang, Hongfei ZhengAbstract:Abstract To reduce energy consumption, the multi-stage type is a promising technology used in the humidification–dehumidification desalination system. Two types of multi-stage desalination system (regenerative and Air-Extraction multi-stage desalination) were proposed, and were studied and improved relatively separately. So, this paper comparatively investigated the two typical desalination systems based on the pinch technology. The pinch analysis models of regenerative and Air-Extraction multi-stage desalination were established and numerically analyzed. Subsequently, the effects of the pinch point temperature difference and the number of stage on the performance of the two desalination systems were comparatively analyzed. The result showed that the Gained Output Ratio (GOR) of regenerative multi-stage desalination was worse than that of Air-Extraction multi-stage desalination, while the Recovery Ratio (RR) of regenerative multi-stage desalination was better. Furthermore, when the single-stage system upgraded to two-stage system, the performance was significantly improved. But as the number of stage increases further, the enhancement effect is gradually weakened and even the performance becomes worse. The research content of this paper will help to select the device in the design of the desalination system.
Teng Wang - One of the best experts on this subject based on the ideXlab platform.
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Comparative analysis of regenerative and Air-Extraction multi-stage humidification–dehumidification desalination system using pinch technology
Desalination, 2016Co-Authors: Huifang Kang, Teng Wang, Hongfei ZhengAbstract:Abstract To reduce energy consumption, the multi-stage type is a promising technology used in the humidification–dehumidification desalination system. Two types of multi-stage desalination system (regenerative and Air-Extraction multi-stage desalination) were proposed, and were studied and improved relatively separately. So, this paper comparatively investigated the two typical desalination systems based on the pinch technology. The pinch analysis models of regenerative and Air-Extraction multi-stage desalination were established and numerically analyzed. Subsequently, the effects of the pinch point temperature difference and the number of stage on the performance of the two desalination systems were comparatively analyzed. The result showed that the Gained Output Ratio (GOR) of regenerative multi-stage desalination was worse than that of Air-Extraction multi-stage desalination, while the Recovery Ratio (RR) of regenerative multi-stage desalination was better. Furthermore, when the single-stage system upgraded to two-stage system, the performance was significantly improved. But as the number of stage increases further, the enhancement effect is gradually weakened and even the performance becomes worse. The research content of this paper will help to select the device in the design of the desalination system.
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comparative analysis of regenerative and Air Extraction multi stage humidification dehumidification desalination system using pinch technology
Desalination, 2016Co-Authors: Huifang Kang, Teng Wang, Hongfei ZhengAbstract:Abstract To reduce energy consumption, the multi-stage type is a promising technology used in the humidification–dehumidification desalination system. Two types of multi-stage desalination system (regenerative and Air-Extraction multi-stage desalination) were proposed, and were studied and improved relatively separately. So, this paper comparatively investigated the two typical desalination systems based on the pinch technology. The pinch analysis models of regenerative and Air-Extraction multi-stage desalination were established and numerically analyzed. Subsequently, the effects of the pinch point temperature difference and the number of stage on the performance of the two desalination systems were comparatively analyzed. The result showed that the Gained Output Ratio (GOR) of regenerative multi-stage desalination was worse than that of Air-Extraction multi-stage desalination, while the Recovery Ratio (RR) of regenerative multi-stage desalination was better. Furthermore, when the single-stage system upgraded to two-stage system, the performance was significantly improved. But as the number of stage increases further, the enhancement effect is gradually weakened and even the performance becomes worse. The research content of this paper will help to select the device in the design of the desalination system.
Klein E. Ileleji - One of the best experts on this subject based on the ideXlab platform.
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simulation and optimization of ion transfer membrane Air separation unit in an igcc power plant
Applied Thermal Engineering, 2018Co-Authors: Guangyi Deng, Qinhui Wang, Hao Zhang, Zheng Li, Klein E. IlelejiAbstract:Abstract Ion transfer membrane (ITM) technology has the potential to lower down energy penalty of Air separation unit (ASU) and consequently promote net efficiency of an integrated gasification combined cycle (IGCC) power plant. This numerical investigation sets up the system model of an IGCC power plant integrated with ITM ASU, aiming to examine influences of Air Extraction rate (0.4–1.0), oxygen separation rate (30–90%) and operation temperature (800–900 °C) on IGCC performances. The advantages of ITM technology over cryogenic ASUs are also evaluated under optimized operation parameters and similar system boundary conditions. Simulation results indicated that increasing Air Extraction rate and oxygen separation rate was beneficial to promote IGCC system net efficiency and reduce auxiliary power consumption rate. Temperature variation had much less influences on system performance, although a minor drop of net efficiency was observed with increasing operation temperatures. The optimized operation parameters were identified as: Air Extraction rates of 0.8–1.0, oxygen separation rates of 70–90% and operation temperature of 800°C. Comparing with the cases using low pressure and high pressure cryogenic ASUs, IGCC net efficiency was increased by 1.0 and 0.6% point when adopting an ITM ASU.
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integration optimisation of elevated pressure Air separation unit with gas turbine in an igcc power plant
Applied Thermal Engineering, 2017Co-Authors: Guangyi Deng, Qinhui Wang, Zheng Li, Klein E. IlelejiAbstract:Abstract The integration optimisation between an elevated pressure Air separation unit (EP-ASU) and gas turbine is beneficial to promote net efficiency of an integrated gasification combined cycle (IGCC) power plant. This study sets up the thermodynamic model for a 400 MW plant specially coupled with an EP-ASU, aiming to examine system performances under different integrations and acquire the optimum solution. Influences of Air Extraction rate at conditions of without, partial and full N2 injection, as well as the effects of N2 injection rate when adopting separate ASU, partial and full integrated ASU were both analysed. Special attention has been paid to performance differences between utilising an EP-ASU and a low pressure unit. Results indicated that integration solution with a separate EP-ASU or without N2 injection would not be reasonable. Among various recommended solutions for different integration conditions, N2 injection rate increased with the growth of Air Extraction rate. The integration with an Air Extraction rate of 80% and full N2 injection was suggested as the optimum solution. It is concluded that the optimum integration solution when adopting an EP-ASU is different from that using a low pressure one.
J. S. Kapat - One of the best experts on this subject based on the ideXlab platform.
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Effect of Air Extraction for Cooling and/or Gasification on Combustor Flow Uniformity
Journal of Engineering for Gas Turbines and Power-transactions of The Asme, 1999Co-Authors: T. Wang, J. S. Kapat, W. R. Ryan, Ihor S. Diakunchak, Ronald L. BannisterAbstract:Reducing emissions is an important issue facing gas turbine manufacturers. Almost all of the previous and current research and development for reducing emissions has focused, however, on flow, heat transfer, and combustion behavior in the combustors or on the uniformity of fuel injection without placing strong emphasis on the flow uniformity entering the combustors. In response to the incomplete understanding of the combustor's inlet Air flow field, experiments were conducted in a 48 percent scale, 360 deg model of the diffuser-combustor section of an industrial gas turbine. In addition, the effect of Air Extraction for cooling or gasification on the flow distributions at the combustors' inlets was also investigated. The following three different Air Extraction rates were studied: 0 percent (baseline), 5 percent (Airfoil cooling), and 20 percent (for coal gasification). The flow uniformity was investigated for the following two aspects: (a) global uniformity, which compared the mass flow rates of combustors at different locations relative to the Extraction port, and (b) local uniformity, which examined the circumferential flow distribution into each combustor. The results indicate that even for the baseline case with no Air Extraction there was an inherent local flow nonuniformity of 10 ∼ 20 percent at the inlet of each combustor due to the complex flow field in the dump diffuser and the blockage effect of the cross-flame tube. More flow was seen in the portion further away from the gas turbine center axis. The effect of 5 percent Air Extraction was small. Twenty percent Air Extraction introduced approximately 35 percent global flow asymmetry diametrically across the dump diffuser. The effect of Air Extraction on the combustor's local flow uniformity varied with the distances between the Extraction port and each individual combustor. Longer top hats were installed with the initial intention of increasing flow mixing prior to entering the combustor. However, the results indicated that longer top hats do not improve the flow uniformity; sometimes, adverse effects can be seen. Although a specific geometry was selected for this study, the results provide sufficient generality to benefit other industrial gas turbines.
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Effect of Air Extraction for Cooling and/or Gasification on Combustor Flow Uniformity
Volume 3: Coal Biomass and Alternative Fuels; Combustion and Fuels; Oil and Gas Applications; Cycle Innovations, 1998Co-Authors: T. Wang, J. S. Kapat, W. R. Ryan, Ihor S. Diakunchak, Ronald L. BannisterAbstract:Reducing emissions is an important issue facing gas turbine manufacturers. Almost all of the previous and current research and development for reducing emissions has focused, however, on flow, heat transfer, and combustion behavior in the combustors or on the uniformity of fuel injection without placing strong emphasis on the flow uniformity entering the combustors. In response to the incomplete understanding of the combustor’s inlet Air flow field, experiments were conducted in a 48% scale, 360° model of the diffuser-combustor section of an industrial gas turbine. In addition, the effect of Air Extraction for cooling or gasification on the flow distributions at the combustors’ inlets was also investigated. Three different Air Extraction rates were studied: 0% (baseline), 5% (Airfoil cooling), and 20% (for coal gasification). The flow uniformity was investigated for two aspects: (a) global uniformity, which compared the mass flow rates of combustors at different locations relative to the Extraction port, and (b) local uniformity, which examined the circumferential flow distribution into each combustor. The results indicate that even for the baseline case with no Air Extraction there was an inherent local flow aonuniformity of 10 ∼ 20% at the inlet of each combustor due to the complex flow field in the dump diffuser and the blockage effect of the cross-flame tube. More flow was seen in the portion further away from the gas turbine center axis. The effect of 5% Air Extraction was small. Twenty-percent Air Extraction introduced approximately 35% global flow asymmetry diametrically across the dump diffuser. The effect of Air Extraction on the combustor’s local flow uniformity varied with the distances between the Extraction port and each individual combustor. Longer top hats were installed with the initial intention of increasing flow mixing prior to entering the combustor. However, the results indicated that longer top hats do not improve the flow uniformity; sometimes, adverse effects can be seen. Although a specific geometry was selected for this study, the results provide sufficient generality to benefit other industrial gas turbines.Copyright © 1998 by ASME
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Experimental studies of Air Extraction for cooling and/or gasification in gas turbine applications
Journal of Engineering for Gas Turbines and Power-transactions of The Asme, 1997Co-Authors: J. S. Kapat, T. Wang, W. R. Ryan, Ihor S. Diakunchak, Ronald L. BannisterAbstract:This paper describes an experimental study on how the flow field inside the dump diffuser of an industrial gas turbine is affected by Air Extraction through a single port on the shell around the dump diffuser. A subscale, 360 deg model of the diffuser-combustor section of an advanced developmental industrial gas turbine was used in this study. The experiments were performed under cold flow conditions, which can be scaled to actual machine operation. Three different conditions were experimentally studied: 0, 5, and 20 percent Air Extraction. It was found that Air Extraction, especially Extraction at the 20 percent rate, introduced flow asymmetry inside the dump diffuser and, in some locations, increased the local flow recirculations. This indicated that when Air was extracted through a single port on the shell, the performance of the dump diffuser was adversely affected with an approximate 7.6 percent increase of the total pressure loss, and the Air flow into the combustors did not remain uniform. The global flow distribution was shown to be approximately 35 percent nonuniform diametrically across the dump diffuser. Although a specific geometry was selected, the results provide sufficient generality for improving understanding of the complex flow behavior in the reverse flow diffuser-combustor sections of gas turbines under the influence of various Air Extractions.
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Experimental Studies of Air Extraction for Cooling and/or Gasification in Gas Turbine Applications
ASME 1996 Turbo Asia Conference, 1996Co-Authors: J. S. Kapat, T. Wang, W. R. Ryan, Ihor S. Diakunchak, Ronald L. BannisterAbstract:This paper describes an experimental study on how the flow field inside the dump diffuser of an industrial gas turbine is affected by Air Extraction through a single port on the shell around the dump diffuser. A sub-scale, 360° model of the diffuser-combustor section of an advanced developmental industrial gas turbine was used in this study. The experiments were performed under cold flow conditions which can be scaled to actual machine operation. Three different conditions were experimentally studied: 0%, 5%, and 20% Air Extraction. It was found that Air Extraction, especially Extraction at the 20% rate, introduced flow asymmetry inside the dump diffuser and, in some locations, increased the local flow recirculations. This indicated that when Air was extracted through a single port on the shell, the performance of the dump diffuser was adversely affected with an approximate 7.6% increase of the total pressure loss, and the Air flow into the combustors did not remain uniform. The global flow distribution was shown to be approximately 35% nonuniform diametrically across the dump diffuser. Although a specific geometry was selected, the results provide sufficient generality for improving understanding of the complex flow behavior in the reverse flow diffuser-combustor sections of gas turbines under the influence of various Air Extractions.Copyright © 1996 by ASME
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Air Extraction in a Gas Turbine for Integrated Gasification Combined Cycle (IGCC): Experiments and Analysis
Volume 3: Coal Biomass and Alternative Fuels; Combustion and Fuels; Oil and Gas Applications; Cycle Innovations, 1994Co-Authors: J. S. Kapat, Ajay K. Agrawal, Tah-teh YangAbstract:This paper presents an investigation of extracting Air from the compressor discharge of a heavy-frame gas turbine. The study was aimed to verify results of an approximate analysis: whether extracting Air from the turbine wrapper would create unacceptable nonuniformity in the flow field inside the compressor discharge casing. A combined experimental and computational approach was undertaken. Cold flow experiments were conducted in an approximately one-third scale model of a heavy-frame gas turbine; a closely approximated 3-D computational fluid dynamic analysis was also performed. This study substantiated the earlier prediction that extracting Air from the turbine wrapper would be undesirable although this method of Air Extraction is simple to retrofit. Prediffuser inlet is suggested as an alternate location for extracting Air. The results show that not only the problem of flow non-uniformity was alleviated with this alternate scheme, but the frictional power loss in the compressor discharge casing was also reduced by a factor of two.Copyright © 1994 by ASME
