Article
Thermodynamics
Davood Hoseinzade, Esmail Lakzian, Ali Hashemian
Summary: This paper proposes using blackbox optimization to obtain the optimal volumetric heating required to reduce wetness at the last stages of steam turbines, achieving improved turbine performance by optimizing the volumetric heating rate. The numerical results show that the optimal rate can significantly enhance turbine performance by improving droplet number and average radius.
Article
Thermodynamics
Xu Han, Jiandong Guan, Qiuliang Zhu, Zhengqi Chen, Bochuan Yao, Wensheng Zhao, Zhonghe Han
Summary: Secondary water droplets in the steam turbine wet steam stage can cause water erosion damage to the rotor cascade, affecting the turbine's operation and efficiency. Controlling the formation of a water film on the stator blade surface is crucial for improving efficiency and safety.
CASE STUDIES IN THERMAL ENGINEERING
(2023)
Article
Thermodynamics
L. Zhang, B. Li, G. B. Chen, Z. C. Yang
Summary: This paper proposes a numerically modified wet steam non-equilibrium condensation (NEC) model by considering the interphase heat and mass transfer. The modified model accurately calculates the distribution characteristics of pressure and droplet radius in wet steam condensing flow. The model provides a theoretical basis for high-accuracy numerical analysis of condensing flow in wet steam turbine cascade.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2023)
Article
Thermodynamics
Guojie Zhang, Xiaogang Wang, Piotr Wisniewski, Jiaheng Chen, Xiang Qin, Slawomir Dykas
Summary: Steam turbine is crucial for energy saving and consumption reduction in power plants. The presence of NaCl affects the condensation process and loss in the turbine, which needs to be considered in future studies.
Article
Thermodynamics
Hongbing Ding, Yu Zhang, Chunqian Sun, Esmail Lakzian, Chuang Wen, Chao Wang
Summary: This research develops a non-equilibrium condensation model with sliding mesh technology to solve the unsteady condensing flow inside a 3D wet steam stage of a steam turbine. The results quantitatively evaluate the condensation loss and entropy generation considering off-design operation and rough blades, and identify the occurrence of secondary expansion and condensation near the rotor trailing edge.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2022)
Article
Thermodynamics
Jalal Salimi, Ali Reza Teymourtash, Mohammad Reza Aghdasi, Esmail Lakzian
Summary: The goal of this study is to find the optimal surface heating technique for a stationary cascade turbine blade in wet steam flow using a genetic algorithm. The research utilizes a numerical method that combines the two-dimensional Navier-Stokes equations with a SSTk-omega turbulence model, and solves nucleation and droplet growth equations using the Eulerian-Eulerian approach. The results show good agreement with established experiments, and it is found that there is an optimum surface heating rate to achieve the best performance of steam turbines.
THERMAL SCIENCE AND ENGINEERING PROGRESS
(2023)
Article
Thermodynamics
Xiaodong Zhao, Ang Li, Youjun Zhang, Liqun Ma, Zhihua Ge, Xiaoze Du
Summary: This study analyzed and optimized the last stage flow field and temperature distribution of the low-pressure cylinder of a high back pressure steam turbine by setting a diversion ring, leading to an increase in efficiency and improvement in aerodynamic performance under different heating conditions.
APPLIED THERMAL ENGINEERING
(2021)
Article
Thermodynamics
Seyed Ehsan Hosseinizadeh, Erfan Ghamati, Ali Jahangiri, Sahand Majidi, Iman Khazaee, Mohammad Ali Faghih Aliabadi
Summary: Steam turbine plays a vital role in industry as a crucial equipment for energy conversion. However, the non-equilibrium condensation in the steam turbine leads to the formation of tiny droplets, which can reduce efficiency and pose safety risks. This study investigates the use of hot steam injection to control droplet size and liquid mass fraction in steam turbine blades, considering friction and thermal entropy generation. The results show that hot steam injection can significantly reduce condensation loss, erosion rate, and blade inlet flow rate, while increasing generated entropy.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2023)
Article
Thermodynamics
Amir Momeni Dolatabadi, Jamshid Moslehi, Mohsen Saffari Pour, Seyed Soheil Mousavi Ajarostaghi, Sebastien Poncet, Muslum Arici
Summary: The study aims to reduce condensing losses of wet steam flow and increase the energy efficiency of steam turbine by injecting Nano-droplets in nucleation zone. The results are validated with experimental data and the SST k-u turbulence model is utilized to simulate the effects of Nano-droplets. Effective energy parameters have been presented, resulting in a significant decrease in condensation losses and improvements in efficient energy and Mach number.
Review
Chemistry, Multidisciplinary
Xiuqiang Li, Wanrong Xie, Jia Zhu
Summary: Interfacial solar steam/vapor technology uses solar energy and water to achieve heating and cooling, which is a promising solution to environmental and energy issues. By designing and optimizing materials, structures, and devices, higher conversion and utilization efficiency can be achieved. This review summarizes recent developments and future trends in this field and discusses unsolved scientific and technical problems.
Article
Mechanics
Seyed Ali Hosseini, Mehdi Nakisa, Esmail Lakzian
Summary: Nowadays, increasing the efficiency and improving the performance of steam turbines is essential due to their significant role in providing energy. Wet steam flow in the low-pressure stage of steam turbines can result in energy loss, efficiency drop, and erosion/corrosion problems. The research investigates the effect of the drainage groove location on the surface of steam turbine blades. The results indicate that the location of the drainage groove impacts the groove performance and flow pattern, reducing liquid drainage, condensation losses, and erosion rate. The findings contribute to the enhancement of the lifetime, repair and maintenance, and output power of steam power generation facilities.
Article
Thermodynamics
Mohammad Ghodrati, Esmail Lakzian, Heuy Dong Kim
Summary: In this study, a channel embedded in the turbine blade has been used to solve the problem of water droplets condensation, making hot steam injection and blade surface heating practical. By utilizing surface heating and hot steam injection, the negative effects of droplets on turbine performance can be reduced, while the kinetic energy conversion efficiency is increased.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2023)
Article
Engineering, Mechanical
Esmail Lakzian, Shima Yazdani, Bok Jik Lee
Summary: This paper discusses a new flow control method and optimization of two-phase flow, aiming to improve thermodynamic efficiency by reducing droplet radius and wetness fraction.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2023)
Article
Engineering, Multidisciplinary
Sima Shabani, Miroslaw Majkut, Slawomir Dykas, Krystian Smolka, Esmail Lakzian
Summary: This study validates and simulates steam condensing flows using different condensation models and equations of state, identifying the most suitable model. The results highlight the importance of choosing the appropriate numerical model for accurately predicting steam condensation flows.
ENGINEERING ANALYSIS WITH BOUNDARY ELEMENTS
(2024)
Article
Thermodynamics
Fan Wu, An Han, Wei Jiang, Yanan Yue, Danmei Xie
Summary: The complex flow field at low load has a significant impact on the aerodynamic performance of steam turbines. To improve performance under low mass-flow conditions, a design of bio-inspired steam turbine blades with biomimetic bumps on the suction side was proposed. Numerical simulation results showed that the bumps generated streamwise vortices, leading to a decrease in pressure on the suction side of the blade. This resulted in improved performance, reflected in the increased output torque.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2022)
Article
Engineering, Mechanical
D. Hoseinzade, E. Lakzian, S. Dykas
Summary: By optimizing the trailing edge rotation, the thermodynamic losses and blade erosion caused by wetness in the low-pressure steam turbine can be reduced. The results show that the optimal trailing edge rotation can improve the targeted goals and decrease the erosion rate and condensation losses.
EXPERIMENTAL TECHNIQUES
(2023)
Article
Engineering, Mechanical
E. Behnamtalab, E. Lakzian, S. B. Hosseini
Summary: This paper studies the effect of USBR VI stilling basin geometry on entropy generation and introduces total entropy generation as a design index, comparing the results with flow characteristics and outlet flow. The study shows that the W/D ratio has a significant impact on flow field, entropy generation rate, and total entropy generation.
EXPERIMENTAL TECHNIQUES
(2023)
Article
Engineering, Mechanical
Esmail Lakzian, Shima Yazdani, Bok Jik Lee
Summary: This paper discusses a new flow control method and optimization of two-phase flow, aiming to improve thermodynamic efficiency by reducing droplet radius and wetness fraction.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2023)
Article
Thermodynamics
Ahmad Jahani Rahvard, Shahram Karami, Esmail Lakzian
Summary: In this paper, a computational fluid dynamic (CFD) model was used to simulate the dispersion of COVID-19 virus in a conference hall when a patient coughs, and the effect of the position of air conditioning system's supply and return registers was investigated. The simulation results showed that when the inlet registers were located on the longitudinal wall, the virus particles were completely removed from the air after 80 seconds, while in other cases, virus particles still remained.
INTERNATIONAL JOURNAL OF REFRIGERATION
(2023)
Article
Thermodynamics
Mohammad Ghodrati, Esmail Lakzian, Amir Kafaei, Wei Mon Yan, Heuy Dong Kim
Summary: By installing a channel inside the 3D turbine blade to allow hot steam storage and injection, it is possible to reduce wet steam losses in steam turbines and affect other key parameters.
APPLIED THERMAL ENGINEERING
(2023)
Article
Energy & Fuels
Sima Shabani, Miroslaw Majkut, Slawomir Dykas, Krystian Smolka, Esmail Lakzian, Guojie Zhang
Summary: The paper discusses the challenges of numerical modeling of condensing steam flows in steam turbines due to the two-phase nature of the flow and the need to treat steam as a real gas. Two different Eulerian approaches were compared and it was found that the choice of numerical schemes and governing equations can greatly affect the modeling of wet steam flows. The results of the numerical simulations were compared to experimental data and although both codes showed good capabilities in predicting the condensation process, there were some differences in the flow field parameters.
Article
Energy & Fuels
Shahram Karami, Esmail Lakzian, Sima Shabani, Slawomir Dykas, Fahime Salmani, Bok Jik Lee, Majid Ebrahimi Warkiani, Heuy Dong Kim, Goodarz Ahmadi
Summary: This study used computational fluid dynamics to simulate the dispersion and transport of respiratory droplets emitted by an infected person coughing in an indoor space with an air ventilation system. The results can help in assessing the risk of infection and developing mitigation measures. The study innovatively used an Eulerian-Lagrangian CFD model for cough droplet dispersion simulation, assessed infection risk using the Wells-Riley equation, and proposed a safer ventilation system design.
Article
Thermodynamics
Seyed Ali Hosseini, Esmail Lakzian, Mehdi Nakisa
Summary: Nowadays, it is important to reduce losses and increase the lifetime of industrial equipment. Steam turbines are crucial equipment in power plants but are expensive, so reducing losses and maintenance are crucial. The last stage of the steam turbine faces the issue of two-phase flow, which reduces efficiency and damages turbine blades. To decrease the liquid phase, the use of drainage grooves is proposed. This paper optimizes the drainage groove variables using TOPSIS method and determines the optimal status as location 3, angle 90, width 0.06, and drainage pressure 80 kPa. In this optimized status, condensation loss and erosion rate decreased, while entropy generated and drainage ratios increased.
INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER
(2023)
Article
Engineering, Chemical
Daryoush Dadpour, Mohammad Gholizadeh, Esmail Lakzian, Mostafa Delpisheh, Heuy Dong Kim
Summary: Advances in technology have resulted in increased energy consumption and global warming. To address this issue, the optimal use of energy is being promoted in accordance with the Paris agreement. Among the sectors responsible for high energy consumption, air conditioning and refrigeration systems have prompted the implementation of optimization measures. This research focuses on utilizing the waste heat from a 2000 cc engine radiator as an alternative to conventional refrigeration cycles in vehicles. The ejector refrigeration cycle is modeled and optimized using TOPSIS multi-objective optimization method, resulting in reduced power consumption, capital investment cost, and increased COP compared to conventional systems.
JOURNAL OF THE TAIWAN INSTITUTE OF CHEMICAL ENGINEERS
(2023)
Article
Environmental Sciences
Mohammadreza Haghdoost, Esmail Lakzian, Reza Norouzi, John Abraham, SeyedMohsen Sajjadi, Javad Ahadiyan
Summary: This research evaluates the effects of penetration depth, distance from the beginning of the crest width, and inclination angle of the internal cutoff wall on design parameters in an embankment dam. The presence of an internal cutoff wall leads to a significant decline in the phreatic line level. Increasing penetration depth decreases seepage flow, while increasing distance from the crest width and inclination angle increases seepage discharge and hydraulic gradient. An internal cutoff wall with an inclination angle of 45 degrees and penetration depth of 24 m has the best performance at reducing seepage by 49.7%.
MODELING EARTH SYSTEMS AND ENVIRONMENT
(2023)
Article
Thermodynamics
Jalal Salimi, Ali Reza Teymourtash, Mohammad Reza Aghdasi, Esmail Lakzian
Summary: The goal of this study is to find the optimal surface heating technique for a stationary cascade turbine blade in wet steam flow using a genetic algorithm. The research utilizes a numerical method that combines the two-dimensional Navier-Stokes equations with a SSTk-omega turbulence model, and solves nucleation and droplet growth equations using the Eulerian-Eulerian approach. The results show good agreement with established experiments, and it is found that there is an optimum surface heating rate to achieve the best performance of steam turbines.
THERMAL SCIENCE AND ENGINEERING PROGRESS
(2023)
Article
Thermodynamics
Seyed Ali Hosseini, Mohammad Reza Aghdasi, Esmail Lakzian, Heuy Dong Kim
Summary: The impacts of inlet steam superheat degree and variation of blade pitch in the turbine blade cascade have been investigated. The optimization of these factors using genetic algorithm has been studied to keep the inlet mass flow rate fixed. Results show that increasing the inlet steam superheat degree decreases the inlet mass flow rate, while increasing the blade pitch can increase the mass flow rate.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2023)
Article
Mechanics
Mohammad Ghodrati, Esmail Lakzian, Heuy Dong Kim
Summary: Injecting hot steam into the cascade flow is a procedure for preventing losses and damages caused by condensation. By utilizing a 3D geometry for steam turbine blades and the TOPSIS optimization method, the best temperature for hot steam injection has been obtained for both constant pressure and constant mass flow rate methods.
Article
Mechanics
Seyed Ali Hosseini, Mehdi Nakisa, Esmail Lakzian
Summary: Nowadays, increasing the efficiency and improving the performance of steam turbines is essential due to their significant role in providing energy. Wet steam flow in the low-pressure stage of steam turbines can result in energy loss, efficiency drop, and erosion/corrosion problems. The research investigates the effect of the drainage groove location on the surface of steam turbine blades. The results indicate that the location of the drainage groove impacts the groove performance and flow pattern, reducing liquid drainage, condensation losses, and erosion rate. The findings contribute to the enhancement of the lifetime, repair and maintenance, and output power of steam power generation facilities.
Article
Engineering, Mechanical
Reza Dolatabadi, Esmail Lakzian, Samaneh Masoumi, Slawomir Dykas, Nader Karimi, Fayssal Benkhaldoun, Mikhail S. Vlaskin
Summary: The design of the rotor stagger angle and operating conditions in the low-pressure stage of the steam turbine can reduce the effects of liquid phase in the wet steam flow, improving turbine efficiency. Simulations and experiments were conducted to determine the optimal rotor stagger angle and outlet pressure, resulting in a significant increase in turbine stage efficiency.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART C-JOURNAL OF MECHANICAL ENGINEERING SCIENCE
(2023)
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.
