Article
Thermodynamics
Marcin Jankowski, Piotr Klonowicz, Aleksandra Borsukiewicz
Summary: Organic Rankine cycle (ORC) power plants are a promising technology for converting low and medium temperature energy sources into electricity. Proper design of the components, including the turboexpander, is crucial for system efficiency. This study focuses on optimizing an ORC system with a one-dimensional radial-inflow turbine model to determine the optimal parameters for turbine geometry.
Article
Thermodynamics
Wenyu Li, Yunyuan Li, Xiang Ling
Summary: This study presents a comprehensive analysis of performance prediction of the ORC radial inflow turbine and proposes a novel turbine performance prediction program. The results show that loss model combinations E, O, and Q perform well in rotor loss prediction.
CASE STUDIES IN THERMAL ENGINEERING
(2021)
Article
Engineering, Chemical
Yuxuan Chen, Zhicheng Zhu, Xiao Li, Yanping Zhang, Wei Gao
Summary: The study shows that the meridian length and circumferential position of the splitter blade have significant effects on the flow field distribution inside the impeller and impeller performance. When the circumferential offset of the splitter blade is around 0.6 and the blade length is around 80% of the length of the main blade, the ORC radial inflow turbine designed in this study achieves optimum performance.
Article
Engineering, Electrical & Electronic
Jiangnan Zhang, Yi Tang
Summary: This study presents a design method for radial-inflow turbines in organic Rankine cycles (ORC). The current circulation method for turbine design lacks real gas capability and 3D blades with high stresses, which makes it unsuitable for ORC turbines. The proposed method decomposes the flow field into potential and rotational parts, solves the velocity fields separately, models real gas properties, and iteratively solves the blade geometry. The method is validated by designing a R245fa ORC turbine rotor.
Article
Thermodynamics
Aki Gronman, Antti Uusitalo
Summary: This study investigates the design of radial-outflow turbines with supercritical carbon dioxide, comparing them to radial inflow turbine designs. The results show that radial outflow turbines can achieve high efficiencies over a wider range of specific speeds, which helps to reduce challenges related to turbomachinery mechanical design.
ENERGY CONVERSION AND MANAGEMENT
(2022)
Article
Thermodynamics
Wenyu Li, Qin Ni, Xiang Ling
Summary: This paper discusses the design and performance prediction methods of radial inflow turbines in organic Rankine cycle (ORC) systems. By establishing a parametric model and studying the influence of geometric parameters on turbine performance, a reasonable three-dimensional geometry design is determined. Then, based on the appropriate geometry design, the off-design performance of the turbine is investigated, and new performance prediction models are constructed and validated under different organic fluid conditions.
CASE STUDIES IN THERMAL ENGINEERING
(2023)
Article
Thermodynamics
Jianhui Qi, Yueming Yang, Kuihua Han, Ming Gao, Yingjie Li, Suoying He, Jinliang Xu
Summary: Radial inflow turbines (RITs) are important for power generation, especially in supercritical CO2 (sCO2) power cycles, due to their compact construction and high power density. However, most preliminary design studies for RITs neglect the importance of stator design and only focus on rotor inlet conditions. This paper presents a workflow for correctly sizing a stator to achieve desired rotor inflow conditions and conducts a stator design-space analysis using an existing 500 kW sCO2 rotor. The results provide valuable insights on adjusting blade angles, managing rotor-stator interaction loss, and considering stator losses in turbine design.
THERMAL SCIENCE AND ENGINEERING PROGRESS
(2023)
Article
Thermodynamics
Angie L. Espinosa Sarmiento, Ramiro G. Ramirez Camacho, Waldir de Oliveira, Elkin Gutierrez Velasquez, Manohar Murthi, Nelson J. Diaz Gautier
Summary: The study describes the design and metamodel-based optimization of an ORC radial-inflow turbine using R245fa as a working fluid. By optimizing the rotor design to maximize efficiency, better blade loading and higher efficiencies were achieved.
APPLIED THERMAL ENGINEERING
(2021)
Article
Engineering, Marine
Yun Chen, Yanjun Liu, Li Zhang, Xiaowei Yang
Summary: This study proposes a design method for a radial inflow turbine suitable for ocean thermal energy conversion, based on parameter optimization. The performance of the turbine in a low temperature difference environment was verified through one-dimensional design and three-dimensional CFD analysis, showing stable internal flow field without obvious backflow or eddy current.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2021)
Article
Thermodynamics
Yunyuan Li, Wenyu Li, Xinyue Gao, Xiang Ling
Summary: Researchers focus on the coupled design and optimization of high-temperature organic Rankine cycle (ORC) system and radial-inflow turbine (RIT), exploring the relationship between turbine performance, thermal efficiency, and size. Siloxane mixtures are proven to be more efficient but require larger turbine and heat exchanger size, while cyclohexane, toluene, m-xylene and hexane are identified as promising working fluids for applications where compact turbine and heat exchanger are needed, such as vehicle waste heat recovery.
APPLIED THERMAL ENGINEERING
(2021)
Article
Thermodynamics
Lukasz Witanowski, Pawel Ziolkowski, Piotr Klonowicz, Piotr Lampart
Summary: Energy conversion efficiency is crucial for power systems and optimizing the components of a power plant can enhance efficiency. This study focuses on the 3D blade shape optimization of a 10 kW single-stage radial inflow turbine using hybrid stochastic/deterministic methods. Eight algorithms, including stochastic, deterministic, and hybrid ones, were compared and principal component analysis was used for process analysis. The optimized geometries showed an efficiency increase of over 2 pp. validated on refined grids, with a total-to-static efficiency of 90.6% achieved at the nominal point using a hybrid method.
Article
Engineering, Multidisciplinary
Jianhui Qi, Bingkun Ma, Kan Qin, Kuihua Han, Jiangwei Liu, Jinliang Xu, Yueming Yang, Yongqing Xiao, Xujiang Wang
Summary: In this study, the stator nozzle of a supercritical CO2 radial inflow turbine (RIT) was optimized using a modularized geometry optimizer. The geometry was parameterized using a parametrized stator mesh generator based on a meridional streamline. Bulk computational fluid dynamics simulations were carried out to form a Pareto front with 14 variables. Three final stators were selected: optimized Mach number distribution (sigma(M)), optimized outlet flow angle distribution (sigma(alpha)), and a compromise case. The outlet boundary properties of these stators were extracted and discussed.
ENGINEERING APPLICATIONS OF COMPUTATIONAL FLUID MECHANICS
(2022)
Article
Thermodynamics
Yanan Gou, Lei Li, Hong Min
Summary: This study focuses on the miniaturization design and performance analysis experiment of the expander in the organic Rankine cycle (ORC) system, studying the effects of temperature, pressure, and rotational speed on the output power, temperature drop, and efficiency of the expander. Experimental results and analysis conclusions are derived from the research.
INTERNATIONAL JOURNAL OF LOW-CARBON TECHNOLOGIES
(2021)
Article
Thermodynamics
Yuqi Wang, Yunzhu Li, Di Zhang, Yonghui Xie
Summary: The study indicates that the improved Simulated Annealing Algorithm (ISAA) can significantly enhance the effectiveness of turbomachinery design, maximize the isentropic efficiency, and save computation time. When the ISAA optimization method is applied to a Brayton cycle power system, there is also an increase in overall system efficiency.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART A-JOURNAL OF POWER AND ENERGY
(2021)
Article
Thermodynamics
L. M. C. Gato, D. N. Ferreira, D. O. C. Sa
Summary: The paper presents a study on the aerodynamic design of self-rectifying biradial turbine rotors for improving efficiency and determining the most efficient specific speed range. A new rotor geometry generation method is proposed, allowing for more design flexibility. The research includes geometry parametrization and flow simulations to understand the effect of design parameters on rotor performance. The results show an increase in efficiency and improved specific speed and diameter compared to the original design.
ENERGY CONVERSION AND MANAGEMENT
(2023)
Article
Thermodynamics
Hai Zhao, Puzhen Gao, Xiaochang Li, Ruifeng Tian, Hongyang Wei, Sichao Tan
Summary: This study numerically investigates the interaction between flow-induced vibration and forced convection heat transfer in a tube bundle. The results show that the impact of flow-induced vibration on heat transfer varies in different flow velocity regions.
APPLIED THERMAL ENGINEERING
(2024)
Article
Thermodynamics
Rohit Chintala, Jon Winkler, Sugirdhalakshmi Ramaraj, Xin Jin
Summary: The current state of fault detection and diagnosis for residential air-conditioning systems is expensive and not suitable for widespread implementation. This paper proposes a cost-effective solution by introducing an automated fault detection algorithm as a screening step before more expensive tests can be conducted. The algorithm uses home thermostats and local weather information to identify thermodynamic parameters and detect high-impact air-conditioning faults.
APPLIED THERMAL ENGINEERING
(2024)
Article
Thermodynamics
A. Azimi, N. Basiri, M. Eslami
Summary: This paper presents a novel optimization algorithm for improving the water-film cooling system of photovoltaic panels, resulting in a significant increase in net energy generation.
APPLIED THERMAL ENGINEERING
(2024)
Article
Thermodynamics
Duc-Thuan Phung, Chin-Hsiang Cheng
Summary: In this study, a novel CFDMD model is used to analyze and investigate the behavior of thermal-lag engines (TLE). The study shows that the CFDMD model effectively captures the thermodynamic behavior of the working gas and the dynamic behavior of the engine mechanism. Additionally, the study explores the temporal evolution of engine speed and the influence of various parameters on shaft power and brake thermal efficiency. The research also reveals the existence of a thermal-lag phenomenon in TLE.
APPLIED THERMAL ENGINEERING
(2024)
Article
Thermodynamics
Haiying Yang, Yinjie Shen, Lin Li, Yichen Pan, Ping Yang
Summary: The purpose of this article is to find a measure to improve the interfacial thermal transfer of graphene/silicon heterojunction. Through molecular dynamics simulation, it is found that surface modification can significantly reduce the thermal resistance, thereby improving the thermal conductivity of the graphene/silicon interface.
APPLIED THERMAL ENGINEERING
(2024)
Article
Thermodynamics
Qiong Wu, Yancheng Wang, Haonan Zhou, Xingye Qiu, Deqing Mei
Summary: This article introduces a visible methanol steam reforming microreactor, which uses an optical crystal as an observation window and measures the reaction temperature in real-time using infrared thermography. The results show that under lower oxygen to carbon ratio conditions, the microreactor has a higher heating rate and a stable gradient in temperature distribution.
APPLIED THERMAL ENGINEERING
(2024)
Review
Thermodynamics
Giulia Manco, Umberto Tesio, Elisa Guelpa, Vittorio Verda
Summary: In the past decade, there has been a growing interest in studying energy systems for the combined management of power vectors. Most of the published works focus on finding the optimal design and operations of Multi Energy Systems (MES). However, for newcomers to this field, understanding how to achieve the desired optimization details while controlling computational expenses can be challenging and time-consuming. This paper presents a novel approach to analyzing the existing literature on MES, with the aim of guiding practical development of MES optimization. Through the discussion of six case studies, the authors provide a mathematical formulation as a reference for building the model and emphasize the impact of different aspects on the problem nature and solver selection. In addition, the paper also discusses the different approaches used in the literature for incorporating thermal networks and storage in the optimization of multi-energy systems.
APPLIED THERMAL ENGINEERING
(2024)
Article
Thermodynamics
Xuepeng Yuan, Caiman Yan, Yunxian Huang, Yong Tang, Shiwei Zhang, Gong Chen
Summary: In this study, a multi-scale microgroove wick (MSMGW) was developed by laser irradiation, which demonstrated superior capillary performance. The surface morphology and performance of the wick were affected by laser scan pitch, laser power, repetition frequency, and scanning speed. The MSMGW showed optimal capillary performance in alumina material and DI water as the working fluid.
APPLIED THERMAL ENGINEERING
(2024)
Article
Thermodynamics
Maofei Mei, Feng Hu, Chong Han
Summary: This paper proposes an effective local search method based on detection of droplet boundaries for understanding the dynamic process of droplet growth during dropwise condensation. The method is validated by comparing with experimental data. The present simulation provides an effective approach to more accurately predict the nucleation site density in future studies.
APPLIED THERMAL ENGINEERING
(2024)
Article
Thermodynamics
Rahul Kumar Sharma, Ashish Kumar, Dibakar Rakshit
Summary: The study explores the use of phase change materials (PCM) as a retrofit with Heating Ventilation and Air-conditioning systems (HVAC) to reduce energy consumption and improve air quality. By incorporating PCM with specific thickness and fin configurations, significant energy savings can be achieved in comparison to standard HVAC systems utilizing R134a. This research provides policymakers with energy-efficient and sustainable solutions for HVAC systems to combat climate change.
APPLIED THERMAL ENGINEERING
(2024)
Article
Thermodynamics
Zhenhua Ren, Xiangjin Meng, Xingang Qi, Hui Jin, Yunan Chen, Bin Chen, Liejin Guo
Summary: This paper investigates the heat transfer mechanism and factors influencing thermal radiation in the process of supercritical water gasification (SCWG) of coal, and proposes a comprehensive numerical model to simulate the process. Experimental validation results show that thermal radiation accounts for a significant proportion of the total heat exchange in the reactor and a large amount of radiant energy exists in the important spectral range of supercritical water. Enhancing radiative heat transfer can effectively increase the temperature of the reaction medium and the gasification rate.
APPLIED THERMAL ENGINEERING
(2024)
Article
Thermodynamics
Mauro Abela, Mauro Mameli, Sauro Filippeschi, Brent S. Taft
Summary: Pulsating Heat Pipes (PHP) are passive two-phase heat transfer devices with a simple structure and high heat transfer capabilities. The actual unpredictability of their dynamic behavior during startup and thermal crisis hinders their large-scale application. An experimental apparatus is designed to investigate these phenomena systematically. The results show that increasing the number of evaporator sections and condenser temperature improves the performance of PHP. The condenser temperature also affects the initial liquid phase distribution and startup time.
APPLIED THERMAL ENGINEERING
(2024)
Article
Thermodynamics
Ke Gan, Ruilian Li, Yi Zheng, Hui Xu, Ying Gao, Jiajie Qian, Ziming Wei, Bin Kong, Hong Zhang
Summary: A 3-dimensional enhanced heat pipe radiator has been developed to improve heat dissipation and temperature uniformity in cooling high-power electronic components. Experimental results show that the radiator has superior heat transfer performance compared to a conventional aluminum fin radiator under different heating powers and wind speed conditions.
APPLIED THERMAL ENGINEERING
(2024)
Article
Thermodynamics
Xinyi Zhang, Shuzhong Wang, Daihui Jiang, Zhiqiang Wu
Summary: This study focuses on recovering waste heat from blast furnace slag using dry centrifugal pelletizing technology. A comprehensive two-dimensional model was developed to analyze heat transfer dynamics and investigate factors influencing heat exchange efficiency. The findings have important implications for optimizing waste heat recovery and ensuring safe operations.
APPLIED THERMAL ENGINEERING
(2024)
Article
Thermodynamics
Xincheng Wu, An Zou, Qiang Zhang, Zhaoguang Wang
Summary: The boosting heat generation rate of high-performance processors is challenging traditional cooling techniques. This study proposes a combined design of active jet intermittency and passive surface modification to enhance heat transfer.
APPLIED THERMAL ENGINEERING
(2024)