Article
Thermodynamics
Abdullah Marashli, Enas Alfanatseh, Mohammad Shalby, Mohamed R. Gomaa
Summary: This study develops a mathematical model of the Single-Effect Solar Absorption Cooling system with Lithium Bromide-Water as working fluid, and investigates its performance and crystallization issue in Ma'an, Jordan. The impact of temperature changing on the system's coefficient of performance and crystallization is analyzed, and the effect of improving heat exchanger solution is also evaluated.
CASE STUDIES IN THERMAL ENGINEERING
(2022)
Article
Green & Sustainable Science & Technology
Nasiru I. Ibrahim, Fahad A. Al-Sulaiman, Shafiqur Rehman, Aminuddin Saat, Farid Nasir Ani
Summary: The economic performance of a novel solar-assisted absorption air conditioning system integrated with absorption energy storage (AES) was evaluated in this study, with a payback period of about 5 years in the Eastern region of Saudi Arabia. The solar-driven absorption chiller in the system can achieve up to 58% energy savings, showcasing its potential for efficient cooling solutions in commercial buildings.
JOURNAL OF CLEANER PRODUCTION
(2021)
Article
Green & Sustainable Science & Technology
Paniz Hosseini
Summary: In this study, a neural network was employed to convert a dual-effect absorption chiller from TRNSYS software into MATLAB software, utilizing real catalog data from a well-known manufacturer. The research focused on analyzing various characteristics to determine the most effective inputs and outputs of the chiller. The findings revealed that a neural network with three concealed layers, each containing ten neurons, a hyperbolic tangent activation function, and a dropout probability of 40% achieved the highest correlation coefficient between anticipated and real data. MATLAB software was then used to conduct a parametric evaluation system on the absorption chiller, showing that as certain parameters improved, the energy output decreased.
SUSTAINABLE ENERGY TECHNOLOGIES AND ASSESSMENTS
(2022)
Article
Engineering, Chemical
Ahmad K. Sleiti, Wahib A. Al-Ammari, Mohammed Al-Khawaja
Summary: The novel hybrid single-slope solar distillation systems integrated with single-effect solar absorption cooling system offer impressive cooling capacity and still productivity with lower costs. By strategically recovering waste heat from different system components, these integrated systems show superior performance compared to conventional systems. Configuration S3 stands out for its highest still productivity and comparable COP with slight increase in collector area.
Article
Chemistry, Multidisciplinary
Adil Al-Falahi, Falah Alobaid, Bernd Epple
Summary: Absorption refrigeration cycle plays a crucial role in thermal cooling processes. This study conducts thermo-economic analysis to compare various solar absorption cooling system configurations, finding that parabolic trough collector combined with H2O-LiBr offers lower design aspects and minimum hourly costs.
APPLIED SCIENCES-BASEL
(2021)
Article
Environmental Sciences
Harsh Kadyan, Anil Kumar Berwal, Radhey Shyam Mishra
Summary: In this study, novel GARIC and HACABO methods based on an ETC-linked vapor absorption refrigeration system were proposed to optimize system efficiency. The simulation model and performance analysis demonstrated the high efficiency and performance of the methods in solar cooling systems.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2022)
Article
Thermodynamics
A. Huicochea
Summary: The coupling of two absorption heat pumps, one conventional and one unconventional, allows for simultaneous cooling and heating using low-grade heat. This novel advanced absorption heat pump operates with three pressure levels to manipulate the temperature of useful heat. The system achieves cooling temperatures between 14 and 20 degrees C and heating temperatures between 80 and 106 degrees C, utilizing water/lithium bromide as the working solution.
Article
Engineering, Multidisciplinary
Soheil Mohtaram, Wu WeiDong, Yashar Aryanfar, Arya Abrishami, Mohammad Omidi, Yang QiGuo, Jorge Luis Garcia Alcaraz, Chen YongBao
Summary: This research paper focuses on the dynamics analysis, 3E assessment, and multi-objective evolutionary optimization of a novel solar Li-Br absorption refrigeration cycle. Using mathematical models, the thermodynamic and economic characteristics of the system were analyzed, and the source of system inefficiency was determined. The results of the research were found to be consistent with previous studies.
SCIENCE CHINA-TECHNOLOGICAL SCIENCES
(2022)
Article
Thermodynamics
Yujie Zhou, Lei Pan, Xu Han, Li Sun
Summary: Lithium bromide absorption refrigeration system (ARS) is a promising solution for utilizing industrial waste heat and improving energy efficiency. In this study, a customized Modelica library is developed for dynamic modeling of the single-effect lithium bromide ARS. The model is validated and used for energy and exergy analysis to optimize the system's performance. Additionally, the dynamic responses of hot/cold water flowrate and temperature are investigated.
APPLIED THERMAL ENGINEERING
(2023)
Article
Green & Sustainable Science & Technology
Eduardo J. C. Cavalcanti, Joao Victor M. Ferreira, Monica Carvalho
Summary: This study focuses on a solar-assisted trigeneration system for residential consumer center, considering different dead state temperatures in the exergy assessment. It found that the COP of the absorption system increases with the temperature of the heat source, and there is a slight decrease in the exergy efficiency of the engine and solar system with the increase of dead state temperature. The analysis of dead state temperatures is useful for exergoeconomic and exergoenvironmental analyses.
SUSTAINABLE ENERGY TECHNOLOGIES AND ASSESSMENTS
(2021)
Review
Chemistry, Physical
Jixiang Gui, Chengcheng Li, Yang Cao, Zhongxin Liu, Yijun Shen, Wei Huang, Xinlong Tian
Summary: The water-energy nexus is facing unprecedented challenges due to population growth, climate change, and environmental pollution. Solar-driven interfacial evaporation (SDIE) is a promising strategy for freshwater harvesting with abundant solar and water energy. By utilizing the energy in the SDIE system, high-efficiency water and electricity co-generation (WEG) hybrid systems can optimize the existing water-energy nexus and promote sustainable development. This review analyzes the energy flow in the SDIE system and summarizes energy-harvesting strategies based on various technologies. It also emphasizes recent advances in WEG hybrid systems, discussing their electric generation mechanism, system structure, efficiency, and future development.
Article
Thermodynamics
Mengkai Xu, Shuhong Li, Zhenghao Jin, Weixue Jiang, Kai Du
Summary: This paper experimentally studied the influence of lithium bromide concentration on the performance of an ammonia-water absorption refrigeration system, finding that 15% lithium bromide concentration was optimal for improving COP and reducing rectification cooling load and operating pressure. The results also showed that using a ternary working fluid can lead to more efficient operation and miniaturization of main components in the system.
APPLIED THERMAL ENGINEERING
(2021)
Article
Thermodynamics
Zhenghao Jin, Shuhong Li, Runfa Zhou, Mengkai Xu, Weixue Jiang, Kai Du
Summary: The study shows that adding TiO2 nanoparticles can improve the performance of the NH3 - H2O - LiBr absorption refrigeration system, increase the system's COP, and 0.3% is the optimal concentration of TiO2 nanoparticles.
INTERNATIONAL JOURNAL OF REFRIGERATION
(2021)
Article
Engineering, Chemical
Bin Li, Xinjun Jing, Junsheng Yuan
Summary: The phase equilibria of the LiBr-Li2SO4-KBr-K2SO4-H2O system and its ternary sub-systems were studied using the isothermal dissolution equilibrium method. The phase diagrams were plotted based on the solubility data of the equilibrium solutions. The LiBr-Li2SO4-H2O system formed two hydrate salts, belonging to the hydrate type I phase diagram, while the KBr-K2SO4-H2O system showed a simple co-saturation type phase diagram without solid solution and double salts. The LiBr-Li2SO4-KBr-K2SO4-H2O system formed a K2SO4·Li2SO4 double salt and exhibited a complex phase diagram with multiple crystallization regions and solubility curves.
Article
Chemistry, Physical
H. Ishaq, I Dincer
Summary: A new configuration of solar energy-driven integrated system for ammonia synthesis and power generation is proposed in this study. The system is analyzed dynamically to explore its performance under different radiation intensities, with focus on parameters such as power production and efficiency. The findings highlight the system's capability in hydrogen and ammonia production, as well as power generation efficiency.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Engineering, Electrical & Electronic
Felix Garcia-Torres, Carlos Bordons, Javier Tobajas, Juan Jose Marquez, Joaquin Garrido-Zafra, Antonio Moreno-Munoz
Summary: An optimal Energy Management System (EMS) for economic re-scheduling is developed to minimize economic losses in a network of interconnected microgrids with hybrid Energy Storage System (ESS) under failure conditions, validated using Model Predictive Control (MPC). The algorithm aims to establish a local energy market within the network of microgrids to achieve lower economic losses compared to participating in intraday or real-time markets.
IEEE TRANSACTIONS ON SMART GRID
(2021)
Article
Automation & Control Systems
J. J. Marquez, A. Zafra-Cabeza, Carlos Bordons, Miguel A. Ridao
Summary: This paper introduces a Model Predictive Control approach for fault mitigation in microgrid energy management. The method detects faults online by comparing real behavior and model residuals, with thresholds determined by qualitative statistical decision theory. True inconsistencies trigger a reconfiguration process.
CONTROL ENGINEERING PRACTICE
(2021)
Article
Thermodynamics
Diogo Ortiz Machado, Gustavo Artur Andrade, Julio Elias Normey-Rico, Carlos Bordons
Summary: This study develops an exergy-based hierarchical control for the ACUREX solar collector field. The control can track references, reject disturbances, and optimize production considering operational constraints and intermittent processes. The findings suggest that the proposed exergy-based controller design provides improved thermodynamic performance and is a suitable strategy for the ACUREX solar field.
Article
Energy & Fuels
Jose M. Aguilar-Lopez, Ramon A. Garcia, Adolfo J. Sanchez, Antonio J. Gallego, Eduardo F. Camacho
Summary: This paper presents a mobile sensor system that uses a team of unmanned aerial vehicles (UAVs) to localize and characterize the shadow of mobile clouds for detecting and estimating low direct normal irradiance (DNI) areas caused by clouds shadows. The simulations show that the algorithm used in this system achieves a similar degree of precision in estimating the shape of the cloud shadow, but with a much faster computational time compared to other algorithms described in literature.
Article
Green & Sustainable Science & Technology
Diogo Ortiz Machado, Adolfo J. Sanchez, Antonio J. Gallego, Gustavo A. de Andrade, Julio E. Normey-Rico, Carlos Bordons, Eduardo F. Camacho
Summary: This paper proposes the first application of a split-range control technique on a concentrating solar collector to improve the production of an absorption plant. Control techniques are simulated and compared in an absorption plant in Spain. The results demonstrate that the proposed controllers significantly reduce the effort of control actuators and improve energy and exergy production.
Article
Automation & Control Systems
A. Sanchez-Amores, P. Chanfreut, J. M. Maestre, E. F. Camacho
Summary: Coalitional control is a distributed control method that adjusts the overall controller structure dynamically to reduce the cooperation burden. This paper proposes a novel coalitional model predictive control approach, in which coupled variables are decomposed into public and private parts and their bounds are negotiated in a distributed manner. Different interaction modes can be triggered based on a threshold. The effectiveness of this control scheme is demonstrated through results on a simulated eight input-coupled tanks plant.
EUROPEAN JOURNAL OF CONTROL
(2022)
Article
Automation & Control Systems
Paula Chanfreut, Jose Maria Maestre, Takeshi Hatanaka, Eduardo F. Camacho
Summary: In coalitional model predictive control, the overall system is controlled by networked agents dynamically arranged into connected clusters that coordinate their actions. The clustering problem is formulated as a binary quadratic program, and the method's performance is illustrated through numerical examples.
IEEE TRANSACTIONS ON CONTROL OF NETWORK SYSTEMS
(2022)
Article
Automation & Control Systems
A. Zafra-Cabeza, J. J. Marquez, Carlos Bordons, Miguel A. Ridao
Summary: Due to the current energy dependence of society, the availability and correct functioning of microgrids are strategic issues to be dealt with. This paper presents a novel Control Reconfiguration framework based on Model Predictive Control (MPC) to manage faults in microgrids. The proposal includes fault detection, isolation, and reconfiguration, using different model predictive controllers. Experiments on a real microgrid have shown the benefits of this method.
CONTROL ENGINEERING PRACTICE
(2023)
Article
Automation & Control Systems
Paula Chanfreut, Jose Maria Maestre, Antonio Ferramosca, Francisco Javier Muros, Eduardo F. F. Camacho
Summary: In this article, a coalitional robust model predictive controller for tracking target sets is presented. The controller dynamically merges local control agents into cooperative coalitions or clusters to achieve an efficient tradeoff between cooperation burden and global performance optimality.
IEEE TRANSACTIONS ON AUTOMATIC CONTROL
(2022)
Proceedings Paper
Automation & Control Systems
J. J. Marquez, A. Zafra-Cabeza, C. Bordons
Summary: The current energy situation and the possibility of depleting fossil fuels have spurred the investment in renewable energy sources for power generation. Microgrids are proposed as a configuration that integrates renewable energy sources into the power system, with the use of control systems to maintain reliability and minimize costs. Fault-tolerant control is introduced as a tool to maintain control objectives even in the presence of faults, requiring fault detection, quantification, and adaptive control. This article presents a fault quantification method based on parity equations and structured residuals to mitigate the consequences of faults in microgrid systems.
Proceedings Paper
Automation & Control Systems
Manuel Sivianes, Ascension Zafra-Cabeza, Carlos Bordons
Summary: The energy network is decentralizing due to the inclusion of distributed energy resources. This paper proposes a distributed energy management platform that utilizes blockchain technology to enable safe peer-to-peer transactions. The performance of the distributed model predictive control scheme is compared with the centralized approach.
2022 EUROPEAN CONTROL CONFERENCE (ECC)
(2022)
Proceedings Paper
Automation & Control Systems
Diogo O. Machado, Adolfo J. Sanchez, Gustavo A. de Andrade, Julio Normey-Rico, Carlos Bordons, Eduardo F. Camacho
Summary: This article introduces a control method for line focus concentrating solar collectors that tracks the desired outlet temperature by manipulating the flow and uses a solar tracking device for defocusing. The article proposes a new approach to use defocusing as a standard manipulated variable combined with the flow and employs a multi-variable non-linear model predictive control technique for simulation.
2022 EUROPEAN CONTROL CONFERENCE (ECC)
(2022)
Proceedings Paper
Computer Science, Interdisciplinary Applications
Manuel Sivianes, Carlos Bordons
Summary: A distributed energy management algorithm utilizing blockchain technology for safe power trades in microgrids is proposed. The blockchain acts as a global aggregator, verifying and evaluating convergence of power trades.
BLOCKCHAIN AND APPLICATIONS
(2022)
Article
Computer Science, Information Systems
Juan Aguilar, C. Bordons, A. Arce, R. Galan
Summary: This paper develops a reconfigurable hierarchical multi-time scale framework that combines dynamic storage virtualization and intent profiling to enable domestic consumers to participate in energy markets with weighted strategies. The intelligent management of individual storage virtualization improves the forecasted economic profit of participating in demand-response programs.
Article
Automation & Control Systems
T. Arauz, J. M. Maestre, R. Romagnoli, B. Sinopoli, E. F. Camacho
Summary: This letter proposes a design method for software rejuvenation in discrete-time, where invariant sets are used to schedule the timing of software refreshes in order to ensure system safety. An LP-based approach is proposed to compute a minimal robust positively invariant (min-RPI) set and the bounded time between software refreshes, applicable to stable and unstable systems. The designed approach is illustrated through a case study of a simulated lab-scale microgrid.
IEEE CONTROL SYSTEMS LETTERS
(2022)
Review
Thermodynamics
Shuling Guo, Ankuo Zhang
Summary: Low-temperature biopreservation is commonly used for medication storage to prolong their shelf life. However, cryo-injury can occur during cryopreservation, making it crucial to find a way to achieve long-term biopreservation without causing harm. The optimal storage temperature for different biomaterials should be investigated to improve storage efficiency. This review discusses the mechanisms of cryo-injury and biopreservation, as well as the reasons for storing biological tissues at various temperature zones. It provides valuable insights for the development of biostorage technology.
INTERNATIONAL JOURNAL OF REFRIGERATION
(2024)
Article
Thermodynamics
M. Mohsin Tanveer, Craig R. Bradshaw, Joe Orosz, Greg Kemp
Summary: This study investigates the optimal geometric parameters for a spool compressor using simulation models, and the results indicate that a eccentricity ratio of 0.75 and L/D ratios between 1-1.5 can maximize the volumetric and isentropic efficiencies.
INTERNATIONAL JOURNAL OF REFRIGERATION
(2024)
Article
Thermodynamics
Kongkuai Ying, Zhenhua Jiang, Wenting Wu, Jinjian Chu, Shaoshuai Liu, Yinong Wu
Summary: The Stirling/pulse tube cryocooler (SPC) is a highly efficient and long-lasting cryocooler for space applications. It has the ability to adjust the inter-stage refrigeration capacity dynamically by controlling the Stirling displacer in the first stage. This paper proposes an SPC with a second-stage active phase shifter (APS) that can control the phase difference at the second-stage hot end in real time. The experimental results show that the SPC with the APS can provide refrigeration capacity at different temperatures, with a minimum temperature of 13.5K.
INTERNATIONAL JOURNAL OF REFRIGERATION
(2024)
Article
Thermodynamics
Ligeng Li, Hua Tian, Kai Liu, Yibo Wu, Xuan Wang, Xingyu Liang, Gequn Shu
Summary: This study focuses on improving the performance of carbon dioxide refrigeration systems by introducing a multi-ejector design with three controllable ejectors. Experimental analysis shows that the system's performance can be significantly improved by adopting an optimum pressure control strategy under different operating conditions.
INTERNATIONAL JOURNAL OF REFRIGERATION
(2024)
Article
Thermodynamics
Joseph Al Khoury, Rabih Al Haddad, Ghiwa Shakrina, Christelle Bou Malham, Haytham Sayah, Chakib Bouallou, Maroun Nemer
Summary: This study investigates two implementation methods for calculating refrigerant thermodynamic properties and compares their performance. The results show that the implicit fitting method significantly speeds up simulation time and offers greater flexibility for modeling complex energy systems.
INTERNATIONAL JOURNAL OF REFRIGERATION
(2024)
Article
Thermodynamics
Mariella Mateo-Villanueva, Rodolfo Echarri
Summary: This article details three models of different complexity levels for predicting the cold production of a solar cooling device and compares their advantages and disadvantages. The results show that the transient model underestimates the cold generation, while the equilibrium model and universal model overestimate it. The transient model is a useful tool for analyzing the impact of different variables in a solar adsorption refrigeration system, while the simpler models can be used for preliminary design and feasibility studies.
INTERNATIONAL JOURNAL OF REFRIGERATION
(2024)
Article
Thermodynamics
Amin M. Elsafi, Majid Bahrami
Summary: The novel spherical micro-absorbers offer high sorption capacity and surface-to-volume ratios, solving issues such as solution carryover and corrosion associated with conventional absorbers.
INTERNATIONAL JOURNAL OF REFRIGERATION
(2024)
