Parametric investigation of particulate flow in interconnected porous media for central particle-heating receiver

이태규,신승원,Said I. Abdel-Khalik 대한기계학회 2018 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.32 No.3

An interconnected porous structure can be utilized to regulate the particle mass flow rate for central Solar particle-heating receivers (SPR) in Concentrated solar power (CSP) systems. The porous structure reduces the speed of the falling particulate material, i.e. increases its residence time within the receiver, thereby allowing a large temperature rise to be achieved in a single pass. An experimentally-validated numerical model of particulate flow within a porous structure was presented in an earlier publication (Lee et al., 2015). In this note, the numerical model is parametrically applied to quantify the effect of various design parameters on the performance of the SPR. The effects of receiver height, porous medium characteristics, and particle size on the mass flux and average particle residence time within the receiver have been quantified. Generalized correlations for the mass flux and average residence time have been developed. These correlations represent the main result of this work; they should aid designers of SPRs in selecting the appropriate range of parameters for their application.

EVOLUTION OF NUCLEAR FUEL MANAGEMENT AND REACTOR OPERATIONAL AID TOOLS

TURINSKY PAUL J.,KELLER PAUL M.,ABDEL-KHALIK HANY S. Korean Nuclear Society 2005 Nuclear Engineering and Technology Vol.37 No.1

In this paper are reviewed the current status of nuclear fuel management and reactor operational aid tools. In addition, we indicate deficiencies in current capabilities and what future research is judged warranted. For the nuclear fuel management review the focus is on light water reactors and the utilization of stochastic optimization methods applied to the lattice, fuel bundle, core loading pattern, and for BWRs the control rod pattern/core flow design decision making problems. Significant progress in addressing separately each of these design problems on a single cycle basis is noted; however, the outstanding challenge of addressing the integrated design problem over multiple cycles under conditions of uncertainty remains to be addressed. For the reactor operational aid tools review the focus is on core simulators, used to both process core instrumentation signals and as an operator aid to predict future core behaviors under various operational strategies. After briefly reviewing the current status of capabilities, a more in depth review of adaptive core simulation capabilities, where core simulator input data are adjusted within their known uncertainties to improved agreement between prediction and measurement, is presented. This is done in support of the belief that further development of adaptive core simulation capabilities is required to further significantly advance the utility of core simulators in support of reactor operational aid tools.

Hybrid-Boost Modular Multilevel Converter-Based Medium-Voltage Multiphase Induction Motor Drive for Subsea Applications

Daoud, Mohamed,Elserougi, Ahmed,Massoud, Ahmed,Bojoi, Radu,Abdel-Khalik, Ayman,Ahmed, Shehab The Korean Institute of Power Electronics 2019 JOURNAL OF POWER ELECTRONICS Vol.19 No.3

This paper proposes a hybrid-boost Modular Multilevel Converter (MMC) for the Medium-Voltage (MV) Variable Speed Drives (VSDs) employed in subsea applications, such as oil and gas recovery. In the presented architecture, a hybrid-boost MMC with a reduced number of semiconductor devices driving a multiphase Induction Machine (IM) is investigated. The stepped output voltage generated by the MMC reduces or eliminates the filtering requirements. Moreover, the boosting capability of the proposed architecture eliminates the need for bulky low-frequency transformers at the converter output terminals. A detailed illustration of the hybrid-boost MMC operation, the expected limitations/constraints, and the voltage balancing technique are presented. A simulation model of the proposed MV hybrid-boost MMC-based five-phase IM drive has been built to investigate the system performance. Finally, a downscaled prototype has been constructed for experimental verification.

Hybrid-Boost Modular Multilevel Converter-Based Medium-Voltage Multiphase Induction Motor Drive for Subsea Applications

Mohamed Daoud,Ahmed Elserougi,Ahmed Massou,Radu Bojoi,Ayman Abdel-Khalik,Shehab Ahmed 전력전자학회 2019 JOURNAL OF POWER ELECTRONICS Vol.19 No.3

This paper proposes a hybrid-boost Modular Multilevel Converter (MMC) for the Medium-Voltage (MV) Variable Speed Drives (VSDs) employed in subsea applications, such as oil and gas recovery. In the presented architecture, a hybrid-boost MMC with a reduced number of semiconductor devices driving a multiphase Induction Machine (IM) is investigated. The stepped output voltage generated by the MMC reduces or eliminates the filtering requirements. Moreover, the boosting capability of the proposed architecture eliminates the need for bulky low-frequency transformers at the converter output terminals. A detailed illustration of the hybrid-boost MMC operation, the expected limitations/constraints, and the voltage balancing technique are presented. A simulation model of the proposed MV hybrid-boost MMC-based five-phase IM drive has been built to investigate the system performance. Finally, a downscaled prototype has been constructed for experimental verification.

Evolution of Nuclear Fuel Management and Reactor Operational Aid Tools

PAUL J. TURINSKY,PAUL M. KELLER,HANY S. ABDEL-KHALIK 한국원자력학회 2005 Nuclear Engineering and Technology Vol.37 No.1

In this paper are reviewed the current status of nuclear fuel management and reactor operational aid tools. In addition, we indicate deficiencies in current capabilities and what future research is judged warranted. For the nuclear fuel management review the focus is on light water reactors and the utilization of stochastic optimization methods applied to the lattice, fuel bundle, core loading pattern, and for BWRs the control rod pattern/core flow design decision making problems. Significant progress in addressing separately each of these design problems on a single cycle basis is noted; however, the outstanding challenge of addressing the integrated design problem over multiple cycles under conditions of uncertainty remains to be addressed. For the reactor operational aid tools review the focus is on core simulators, used to both process core instrumentation signals and as an operator aid to predict future core behaviors under various operational strategies. After briefly reviewing the current status of capabilities, a more in depth review of adaptive core simulation capabilities, where core simulator input data are adjusted within their known uncertainties to improved agreement between prediction and measurement, is presented. This is done in support of the belief that further development of adaptive core simulation capabilities is required to further significantly advance the utility of core simulators in support of reactor operational aid tools.

An Adaptive Model Based on Data-driven Approach for FCS-MPC Forming Converter in Microgrid

Ahmed S. Omran,Mostafa S. Hamad,M. Abdelgeliel,Ayman S. Abdel-Khalik 제어·로봇·시스템학회 2023 International Journal of Control, Automation, and Vol.21 No.11

This paper proposes a data-driven approach strategy for enhancing the performance of grid forming converters (GFCs) in microgrids by leveraging the capabilities of dynamic mode decomposition (DMD) in combination with finite-control-set model predictive control (FCS-MPC). Conventional FCS-MPC, based on static models, have encountered numerous challenges in addressing parametric uncertainties in microgrid applications. To address this, the proposed strategy introduces an adaptive model based on DMD, integrated into the FCS-MPC framework to yield a more robust and reliable control technique in the presence of parametric uncertainties. The proposed datadriven approach utilizes the DMD-based model in combination with FCS-MPC to effectively share power through primary control and maintain voltage and frequency stability through secondary control, thus achieving improved reference tracking, load power variation robustness, and power quality. The effectiveness and efficiency of this proposed data-driven approach were validated through a comparative study with conventional static model FCS-MPC and double loop PI control, utilizing the MATLAB/Simulink platform.