Article
Thermodynamics
Biao Lei, Qing-Zhi Yan, Yu-Ting Wu, Chong-Fang Ma, Li-Li Shen, Xiang Li
Summary: By investigating the energy conversion mechanism of Single Screw Expander with exhaust Kinetic energy Utilization (SSEKU) and developing a mathematical model, it was found that introducing exhaust kinetic energy utilization process can effectively reduce under-expansion losses, especially in large size expanders. The maximum increase in isentropic efficiency for expanders with different screw diameters was also determined.
ENERGY CONVERSION AND MANAGEMENT
(2021)
Article
Thermodynamics
Biao Lei, Hai-bin Yu, Guo-qiang Li, Yu-Ting Wu, Wei Wang
Summary: Organic Rankine Cycle (ORC) technology is an effective way to generate power from low or medium grade energy. Utilizing hermetic expanders with internal generators has become an important direction in the development of ORC systems. This paper introduces three cooling schemes for the internal generators in hermetic expanders and quantitatively analyzes their influences on ORC systems.
Article
Thermodynamics
Zhiqi Wang, Yabin Zhao, Xiaoxia Xia, Huihui Pan, Sifeng Zhang, Zhipeng Liu
Summary: This study established a small-scale organic Rankine cycle experimental apparatus with a scroll expander and tested the system performance using different zeotropic mixtures. The results showed that an appropriate mass fraction of zeotropic mixture can improve the thermal efficiency and exergy efficiency of the system.
Article
Thermodynamics
Saif Alshammari, Sambhaji T. Kadam, Zhibin Yu
Summary: This paper investigates the potential of a new single rotor expander-compressor device in a combined Vapor Compression Refrigeration (VCR) cycle and an organic Rankine cycle (ORC). The study finds that the combined cycle has high cooling effect and energy efficiency under specific temperature conditions, which can reduce greenhouse gas emissions.
Article
Thermodynamics
Hai-Xiao Wang, Biao Lei, Yu -Ting Wu
Summary: Organic Rankine cycle (ORC) is important in addressing energy shortage and climate change. This study investigates the cross-seasonal performance of ORC under variable condensation conditions and improves its performance using a single screw expander. The results show the correlation between ORC performance and wet-bulb temperature, as well as the influence of cooling water flow rate on the expansion process. Decreasing pipeline impedance coefficients can effectively optimize ORC system performance.
APPLIED THERMAL ENGINEERING
(2023)
Article
Energy & Fuels
Fabian Dawo, Sebastian Eyerer, Roberto Pili, Christoph Wieland, Hartmut Spliethoff
Summary: Organic Rankine Cycles (ORC) are a promising technology for converting low temperature heat sources into power, but detailed component models are necessary for design. This study conducted systematic experimental investigations and validated a semi-empirical model of twin-screw expanders to determine the optimum built-in volume ratio, achieving a maximum isentropic efficiency of 64%.
Article
Thermodynamics
Xiaoya Li, Steven Lecompte, Jera Van Nieuwenhuyse, Kenny Couvreur, Hua Tian, Gequn Shu, Michel De Paepe, Christos N. Markides
Summary: The study introduced the potential of liquid-flooded expansion technology in enhancing the performance of the basic ORC, with experiments showing improved expander power output and isothermal efficiency. Increasing the amount of liquid flooding can further enhance the power output and thermal efficiency of the system, suggesting the potential for performance improvement by modifying the cycle thermodynamics itself.
ENERGY CONVERSION AND MANAGEMENT
(2021)
Article
Thermodynamics
Fabio Fatigati, Diego Vittorini, Arianna Coletta, Roberto Cipollone
Summary: Organic Rankine Cycle (ORC)-based power unit is a suitable solution for combined heat and power (CHP) generation in the residential sector. This paper focuses on the experimental assessment and modeling of an ORC-based plant equipped with both a custom-designed sliding vane rotary (SVRE) expander and a scroll expander. The comparative analysis provides insights on the advantage of both technologies and the different operating strategies required in each case.
ENERGY CONVERSION AND MANAGEMENT
(2022)
Article
Thermodynamics
Shengming Dong, Xiaowei Hu, Jun Fang Huang, Tingting Zhu, Yufeng Zhang, Xiang Li
Summary: This study investigated the potential of expander speed regulation for optimizing the performance of an ORC system under off-design working conditions. It identified two different optimal speeds for maximum power output and efficiency. Energy and exergy analyses showed the close relationship between expander speed and actual exergy destruction, highlighting the importance of expander and pump optimization for ORC system performance.
Article
Thermodynamics
Hao Guo, Maoqiong Gong, Hailiang Sun
Summary: This paper proposes a novel energy storage system based on reverse organic Rankine cycle, which achieves high efficiency and stable operation through thermodynamic optimization and parametric analysis, and can utilize off-the-shelf commercial products, particularly suitable for unit distributed systems.
Article
Chemistry, Multidisciplinary
Yongning He, Huihong Wu, Yeqiang Zhang, Tingxiang Jin, Ziwen Xing
Summary: This paper experimentally investigates the influence of suction ports on the performance of twin screw expanders. It finds that rotation speed and pressure have significant effects on the suction process and performance, while discharge pressure has little effect.
APPLIED SCIENCES-BASEL
(2022)
Article
Thermodynamics
Yong-qiang Feng, Hui-jie Liang, Kangjing Xu, Yu Wang, Yuanyuan Lu, Chih-Hung Lin, Tzu-Chen Hung
Summary: An improved 10 kW ORC experimental prototype with a scroll-type expander is built, incorporating improvements to the lubricant oil loop. The effects of heat supply, expander pressure difference, and degree of superheat on net power and net power-generating efficiency are discussed, and a comparison between the improved and original 10 kW ORC systems is conducted. The results show that the improved system achieves higher net power and net power-generating efficiency, with significant increases observed with the expander pressure difference.
Article
Thermodynamics
Yong-qiang Feng, Jing-wei Xu, Zhi-xia He, Tzu-Chen Hung, Meng Shao, Fei-yang Zhang
Summary: This study investigates the operation characteristics of the scroll expander in a small-scale organic Rankine cycle through numerical simulation and optimal design, discussing the effects of key parameters on the expander output power and isentropic efficiency. The study yields the optimal solution using response surface methodology and indicates potential improvements in expander efficiency.
Article
Thermodynamics
Fabian Dawo, Jonathan Buhr, Christopher Schifflechner, Christoph Wieland, Hartmut Spliethoff
Summary: This paper investigates the performance of a variant of the Organic Rankine Cycle (ORC) called the partially evaporated ORC (PEORC) compared to the conventional ORC. The results show that the PEORC outperforms the ORC in terms of exergy efficiency due to the better matching of temperature profiles. However, the net thermal efficiency is higher with the ORC due to the higher exergy level of the working fluid.
APPLIED THERMAL ENGINEERING
(2023)
Article
Green & Sustainable Science & Technology
Maximilian Weitzer, Dominik Mueller, Juergen Karl
Summary: This paper focuses on Carnot batteries using heat pumps and organic Rankine cycles, discussing the impact of partial evaporation and flash evaporation on efficiency, and analyzing three cycles in three steps.
Article
Thermodynamics
Ian H. Bell, Davide Ziviani, Vincent Lemort, Craig R. Bradshaw, Margaret Mathison, W. Travis Horton, James E. Braun, Eckhard A. Groll
INTERNATIONAL JOURNAL OF REFRIGERATION
(2020)
Article
Thermodynamics
Xinye Zhang, Davide Ziviani, James E. Braun, Eckhard A. Groll
INTERNATIONAL JOURNAL OF REFRIGERATION
(2020)
Article
Thermodynamics
Riley B. Barta, Davide Ziviani, Eckhard A. Groll
INTERNATIONAL JOURNAL OF REFRIGERATION
(2020)
Article
Engineering, Mechanical
Xinye Zhang, Davide Ziviani, James E. Braun, Eckhard A. Groll
Summary: Recently, linear compressor technology has gained attention for its compactness and lower frictional losses. This paper presents a gas bearing model for a linear compressor based on a Finite Volume Method, which analyzes the dynamic characteristics of gas bearings on the gas film pressure field. By integrating this model with a comprehensive dynamic linear compressor model, it is possible to predict overall performance as well as leakage and frictional losses within the compressor.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART E-JOURNAL OF PROCESS MECHANICAL ENGINEERING
(2022)
Article
Thermodynamics
Ammar M. Bahman, Davide Ziviani, Eckhard A. Groll
INTERNATIONAL JOURNAL OF REFRIGERATION
(2020)
Article
Thermodynamics
Tyler J. Shelly, Justin A. Weibel, Davide Ziviani, Eckhard A. Groll
Summary: This study focuses on the performance of thermal management systems of battery electric vehicles (BEV), comparing different architectures under various conditions. It proposes a novel low-temperature waste heat recovery (LT WHR) system that can increase range at low temperatures.
APPLIED THERMAL ENGINEERING
(2021)
Article
Construction & Building Technology
Ammar M. Bahman, Towhid Parikhani, Davide Ziviani
Summary: This study optimized a two-stage vapor injected heat pump system for residential applications in low ambient temperatures using various working fluids. The system model was simulated through NSGA-II method to obtain Pareto-Frontier curves, and the final decision-making solution was selected based on TOPSIS method.
JOURNAL OF BUILDING ENGINEERING
(2022)
Article
Energy & Fuels
Patrick Krane, Austin L. Nash, Davide Ziviani, James E. Braun, Amy M. Marconnet, Neera Jain
Summary: This paper presents the application of metal hydrides in energy storage, hydrogen storage, and air-conditioning systems. A nonlinear dynamic model and multivariate control strategy are proposed for a two-reactor system, allowing for cyclic use of hydrogen and achieving desired heat transfer rates even in the presence of varying fluid inlet temperatures.
Review
Thermodynamics
M. Mohsin Tanveer, Craig R. Bradshaw, Xin Ding, Davide Ziviani
Summary: This article comprehensively reviews different methods used to model geometry, mass flow, valves, and heat transfer processes in compressors. It aims to help researchers identify suitable approaches for their analysis. Additionally, it highlights opportunities for further research in areas such as developing analytical correlations for discharge coefficients in mass flow models, exploring solubility in leakage gaps, developing effective flow/force area estimation for valve models, and developing instantaneous heat transfer coefficients for specific compressor architectures and thermal conductance models for multi-lumped network models.
INTERNATIONAL JOURNAL OF REFRIGERATION
(2022)
Article
Thermodynamics
Junyoung Kim, James E. Braun, Eckhard A. Groll, Davide Ziviani
Summary: Selecting appropriate working fluids is crucial for improving the technology readiness level of electrochemical heat pumps. This paper develops and evaluates key metrics to identify electrochemically active working fluids and applies them in fluid screening. The screening framework can be employed for other chemical compounds, expanding the design space of electrochemical heat pumps.
INTERNATIONAL JOURNAL OF REFRIGERATION
(2023)
Article
Green & Sustainable Science & Technology
Amin Isazadeh, Davide Ziviani, David E. Claridge
Summary: In the past decade, the demand for data center and network services has significantly increased. Technological advancements have led to a rise in global average rack power density and a decrease in Average Power Usage Effectiveness (PUE). The industry is moving towards more energy-efficient and sustainable technologies to address issues such as fossil fuel depletion, greenhouse gas emissions, electronic waste, and rising energy costs. These technologies include the use of renewable energy, efficient cooling systems, waste heat recovery, passive cooling, and energy storage.
RENEWABLE & SUSTAINABLE ENERGY REVIEWS
(2023)
Article
Chemistry, Multidisciplinary
Abhiroop Mishra, Junyoung Kim, Michelle Zorigt, Adolfo I. B. Romo, Raghuram Gaddam, James E. Braun, Davide Ziviani, Joaquin Rodriguez-Lopez
Summary: Air conditioning, space heating, and refrigeration consume a large amount of electricity in the U.S. buildings, accounting for around 40% of the total usage. The development of energy efficient heat pump technologies is crucial to improve the energy consumption in this sector. Electro-chemical looping heat pump (ELHP) technology shows promise as an alternative to traditional vapor compression systems, offering potential improvements in performance and energy consumption. In this study, the oxidation of isopropanol (IPA) to acetone mediated by 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) was investigated as a promising system for ELHP, with 4-Methoxy-TEMPO identified as the most promising candidate.
ACS SUSTAINABLE CHEMISTRY & ENGINEERING
(2023)
Article
Chemistry, Multidisciplinary
Junyoung Kim, Abhiroop Mishra, James E. Braun, Eckhard A. Groll, Joaquin Rodriguez-Lopez, Davide Ziviani
Summary: In order to reduce energy consumption and improve energy utilization in space conditioning, advanced heat pumping technologies are required. The chemical looping heat pump (CLHP) is a thermodynamic cycle that has the potential to increase the cooling coefficient of performance (COPc) by over 20% compared to conventional vapor compression systems. This paper demonstrates the key process of the CLHP experimentally and predicts the system performance and non-ideal behavior using component-level models. The results show the feasibility of electrochemical phase change and the potential for achieving higher COPc with improved conversion in an electrochemical cell.
CELL REPORTS PHYSICAL SCIENCE
(2023)
Article
Thermodynamics
Weigang Hou, Haotian Liu, James E. Braun, Eckhard A. Groll, Davide Ziviani
Summary: The use of electronic expansion valves (EEVs) in heat pump systems has increased rapidly in recent years due to their advantages. However, there is currently no available experimental data or correlation for EEVs specifically on the low-GWP refrigerant R454C. This study presents experimental results and characterization of R454C flowing through an EEV in a heat pump split system across a wide range of operational conditions. Two semi-empirical correlations were developed to predict the mass flow rate.
INTERNATIONAL JOURNAL OF REFRIGERATION
(2023)
Article
Thermodynamics
Jie Ma, Xin Ding, W. Travis Horton, Davide Ziviani
INTERNATIONAL JOURNAL OF REFRIGERATION
(2020)
Article
Thermodynamics
Yong Cheng, Fukai Song, Lei Fu, Saishuai Dai, Zhiming Yuan, Atilla Incecik
Summary: This paper investigates the accessibility of wave energy absorption by a dual-pontoon floating breakwater integrated with hybrid-type wave energy converters (WECs) and proposes a hydraulic-pneumatic complementary energy extraction method. The performance of the system is validated through experiments and comparative analysis.
Article
Thermodynamics
Jing Gao, Chao Wang, Zhanwu Wang, Jin Lin, Runkai Zhang, Xin Wu, Guangyin Xu, Zhenfeng Wang
Summary: This study aims to establish a new integrated method for biomass cogeneration project site selection, with a focus on the application of the model in Henan Province. By integrating Geographic Information System and Multiple Criterion Decision Making methods, the study conducts site selection in two stages, providing a theoretical reference for the construction of biomass cogeneration projects.
Article
Thermodynamics
Mert Temiz, Ibrahim Dincer
Summary: The current study presents a hybrid small modular nuclear reactor and solar-based system for sustainable communities, integrating floating and bifacial photovoltaic arrays with a small modular reactor. The system efficiently generates power, hydrogen, ammonia, freshwater, and heat for residential, agricultural, and aquaculture facilities. Thermodynamic analysis shows high energy and exergy efficiencies, as well as large-scale ammonia production meeting the needs of metropolitan areas. The hybridization of nuclear and solar technologies offers advantages of reliability, environmental friendliness, and cost efficiency compared to renewable-alone and fossil-based systems.
Editorial Material
Thermodynamics
Wojciech Stanek, Wojciech Adamczyk
Article
Thermodynamics
Desheng Xu, Yanfeng Li, Tianmei Du, Hua Zhong, Youbo Huang, Lei Li, Xiangling Duanmu
Summary: This study investigates the optimization of hybrid mechanical-natural ventilation for smoke control in complex metro stations. The results show that atrium fires are more significantly impacted by outdoor temperature variations compared to concourse/platform fires. The gathered high-temperature smoke inside the atrium can reach up to 900 K under a 5 MW train fire energy release. The findings provide crucial engineering insights into integrating weather data and adaptable ventilation protocols for smoke prevention/mitigation.
Article
Thermodynamics
Da Guo, Heping Xie, Mingzhong Gao, Jianan Li, Zhiqiang He, Ling Chen, Cong Li, Le Zhao, Dingming Wang, Yiwei Zhang, Xin Fang, Guikang Liu, Zhongya Zhou, Lin Dai
Summary: This study proposes a new in-situ pressure-preserved coring tool and elaborates its pressure-preserving mechanism. The experimental and field test results demonstrate that this tool has a high pressure-preservation capability and can maintain a stable pressure in deep wells. This study provides a theoretical framework and design standards for the development of similar technologies.
Article
Thermodynamics
Aolin Lai, Qunwei Wang
Summary: This study assesses the impact of China's de-capacity policy on renewable energy development efficiency (REDE) using the Global-MSBM model and the difference-in-differences method. The findings indicate that the policy significantly enhances REDE, promoting technological advancements and marketization. Moreover, regions with stricter environmental regulations experience a higher impact.
Article
Thermodynamics
Mostafa Ghasemi, Hegazy Rezk
Summary: This study utilizes fuzzy modeling and optimization to enhance the performance of microbial fuel cells (MFCs). By simulating and analyzing experimental data sets, the ideal parameter values for increasing power density, COD elimination, and coulombic efficiency were determined. The results demonstrate that the fuzzy model and optimization methods can significantly improve the performance of MFCs.
Article
Thermodynamics
Zhang Ruan, Lianzhong Huang, Kai Wang, Ranqi Ma, Zhongyi Wang, Rui Zhang, Haoyang Zhao, Cong Wang
Summary: This paper proposes a grey box model for fuel consumption prediction of wing-diesel hybrid vessels based on feature construction. By using both parallel and series grey box modeling methods and six machine learning algorithms, twelve combinations of prediction models are established. A feature construction method based on the aerodynamic performance of the wing and the energy relationship of the hybrid system is introduced. The best combination is obtained by considering the root mean square error, and it shows improved accuracy compared to the white box model. The proposed grey box model can accurately predict the daily fuel consumption of wing-diesel hybrid vessels, contributing to operational optimization and the greenization and decarbonization of the shipping industry.
Article
Thermodynamics
Huayi Chang, Nico Heerink, Junbiao Zhang, Ke He
Summary: This study examines the interaction between off-farm employment decisions between couples and household clean energy consumption in rural China, and finds that two-paycheck households are more likely to consume clean energy. The off-farm employment of women is a key factor driving household clean energy consumption to a higher level, with wage-employed wives having a stronger influence on these decisions than self-employed ones.
Article
Thermodynamics
Hanguan Wen, Xiufeng Liu, Ming Yang, Bo Lei, Xu Cheng, Zhe Chen
Summary: Demand-side management is crucial to smart energy systems. This paper proposes a data-driven approach to understand the relationship between energy consumption patterns and household characteristics for better DSM services. The proposed method uses a clustering algorithm to generate optimal customer groups for DSM and a deep learning model for training. The model can predict the possibility of DSM membership for a given household. The results demonstrate the usefulness of weekly energy consumption data and household socio-demographic information for distinguishing consumer groups and the potential for targeted DSM strategies.
Article
Thermodynamics
Xinglan Hou, Xiuping Zhong, Shuaishuai Nie, Yafei Wang, Guigang Tu, Yingrui Ma, Kunyan Liu, Chen Chen
Summary: This study explores the feasibility of utilizing a multi-level horizontal branch well heat recovery system in the Qiabuqia geothermal field. The research systematically investigates the effects of various engineering parameters on production temperature, establishes mathematical models to describe their relationships, and evaluates the economic viability of the system. The findings demonstrate the significant economic feasibility of the multi-level branch well system.
Article
Thermodynamics
Longxin Zhang, Songtao Wang, Site Hu
Summary: This investigation reveals the influence of tip leakage flow on the modern transonic rotor and finds that the increase of tip clearance size leads to a decline in rotor performance. However, an optimal tip clearance size can extend the rotor's stall margin.
Article
Thermodynamics
Kristian Gjoka, Behzad Rismanchi, Robert H. Crawford
Summary: This paper proposes a framework for assessing the performance of 5GDHC systems and demonstrates it through a case study in a university campus in Melbourne, Australia. The results show that 5GDHC systems are a cost-effective and environmentally viable solution in mild climates, and their successful implementation in Australia can create new market opportunities and potential adoption in other countries with similar climatic conditions.
Article
Thermodynamics
Jianwei Li, Guotai Wang, Panpan Yang, Yongshuang Wen, Leian Zhang, Rujun Song, Chengwei Hou
Summary: This study proposes an orientation-adaptive electromagnetic energy harvester by introducing a rotatable bluff body, which allows for self-regulation to cater for changing wind flow direction. Experimental results show that the output power of the energy harvester can be greatly enhanced with increased rotatory inertia of the rotating bluff body, providing a promising solution for harnessing wind-induced vibration energy.
