Article
Engineering, Chemical
Tianning Zhang, Youjun Lu
Summary: This paper investigates the heat transfer characteristics between the wall and bed in SCWFB, comparing the accuracy of different methods in predicting heat transfer coefficients, and studying the influence of factors such as temperature, pressure, and velocity on heat transfer characteristics.
Article
Mechanics
Kenan Xi, Hao Wang, Youjun Lu
Summary: Supercritical water circulating fluidized beds (SCWCFBs) were investigated using a two-fluid model to study flow dynamics. The study focused on various factors such as flow velocities, solid circulation rates, pressures, and temperatures. The results showed similarities between SCWCFB risers and traditional gas-solid risers. The void fraction distributions ranged from 0.85 to 0.95, with lower values at the bottom and near the walls, and higher values at the top and center. The particle velocities exhibited annular-core flow structures, with upward velocities near the axis and downward velocities near the walls. The fluid paths were tortuous at low velocities but straight at high velocities. The particle drag forces were around 0.7-0.8 times the particle weights. The effects of pressures on flow dynamics were attributed to changes in density and viscosity, affecting the fluid's ability to carry particles.
Article
Thermodynamics
Dongfang Li, Kyeongho Kim, Minwoo Kim, Yijie Zeng, Zhongzhi Yang, Sangho Lee, Xiaofeng Lu, Chung-Hwan Jeon
Summary: This study investigated the effect of particle size on bed-to-surface heat transfer in a bubbling FBHE of a 550 MWe ultra-supercritical CFB boiler. Experimental results showed that heat transfer coefficient increases with decreasing particle sizes. Improving cyclone efficiency to achieve finer particle size can enhance heat transfer in FBHE.
Article
Engineering, Chemical
Wenjian Cai, Shuyan Wang, Mustafa Ahmed Khogley Ahmed, Weiqi Chen, Huilin Lu
Summary: Numerical simulations were conducted to investigate the mixing and segregation of flotsam and jetsam components in a binary mixture in a supercritical water fluidized bed. The results indicated that increasing the temperature and fluidizing velocity of the supercritical water contributes to the mixing of the components along the bed height.
CHEMICAL ENGINEERING SCIENCE
(2021)
Article
Engineering, Chemical
Xiaoge Zhang, Youjun Lu
Summary: This work presents two dynamic models of the supercritical water fluidized bed, and compares their performance. The 1.5D model shows lower error in hydrogen molar fraction and stabilizes faster with higher steady-state values. The study also finds that coal-to-water ratios and supercritical water temperature affect the gasification process.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2022)
Article
Thermodynamics
Min Ji Lee, Suyoung Kim, Sung Won Kim
Summary: This study investigated the wall-to-bed heat transfer characteristics of multi-walled carbon nanotubes in a fluidized bed. Different shapes of carbon nanotube particles led to different gas channeling phenomena, which affected the bed hydrodynamics. The heat transfer coefficient increased with gas velocity, and the shape of the nanotubes influenced the rate of increase.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2023)
Article
Thermodynamics
Shahong Zhu, Man Zhang, Boyu Deng, Zhong Huang, Yi Ding, Gang Wang, Hairui Yang, Guangxi Yue
Summary: In this paper, a steady state and dynamic flowsheet model of a 350 MWe supercritical CFB boiler was developed and validated. The dynamic characteristics of step signal disturbances were analyzed to provide theoretical references to dynamic operation. In addition, the quantitative relation between stabilization time and amplitude was calculated.
APPLIED THERMAL ENGINEERING
(2022)
Article
Thermodynamics
Yunan Chen, Lei Yi, Jiarong Yin, Hui Jin, Liejin Guo
Summary: The study investigated the supercritical water gasification of sewage sludge in a fluidized bed reactor, focusing on the effects of temperature on product distribution and gas compositions. It was found that increasing temperature enhanced the dissolution and hydrolysis of organic matter in the sludge, leading to increased gas production. Furthermore, temperature elevation also induced dehydrogenation and polymerization reactions, which could be explained by the Diels-Alder mechanism.
Article
Thermodynamics
K. Nanan, S. Eiamsa-ard, S. Chokphoemphun, Manoj Kumar, M. Pimsarn, V. Chuwattanakul
Summary: The aim of this study was to investigate the shrimp drying process in a fluidized-bed dryer in order to develop a more efficient method compared to traditional sun drying. The influence of shrimp size, bed height, and air temperature on the drying rate was studied, with the moisture content of boiled shrimp decreasing at higher drying temperatures. Reducing bed height and shrimp size both increased shrimp moisture removal. The highest dried shrimp production rate was achieved at a bed height of 1.0 and drying temperature of 80 degrees C.
CASE STUDIES IN THERMAL ENGINEERING
(2023)
Review
Green & Sustainable Science & Technology
Congcong Wu, Haitao Yang, Xiaohei He, Chaoquan Hu, Le Yang, Hongtao Li
Summary: This paper briefly introduces the principle and practical application of fluidized bed heat exchange technology (FBHET), focusing on the research progress of heat transfer, anti-fouling, and flow characteristics of fluidized bed. Innovative suggestions on the development direction and application field of FBHET are proposed.
RENEWABLE & SUSTAINABLE ENERGY REVIEWS
(2022)
Article
Energy & Fuels
Kui Luo, Chenchen Zhou, Yu Wang, Zhiyong Peng, Libo Lu, Hui Jin, Liejin Guo
Summary: This study integrates the hydrogen oxidation process into a supercritical water fluidized bed to provide heat for the gasification process and achieves high gasification efficiency and H2 yield. The heating method based on hydrogen oxidation process has obvious advantages compared with other methods.
Article
Engineering, Environmental
Dali Kong, Kun Luo, Shuai Wang, Jiahui Yu, Jianren Fan
Summary: The study uses a particle-scale computational fluid dynamics-discrete element method to investigate biomass gasification in a bubbling fluidized bed reactor, exploring the effects of operating temperature and steam to biomass ratio on particle mixing and heat transfer modes. Increasing operating temperature and S/B ratio can enhance biomass mixing index and promote chemical reactions and heat transfer.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Engineering, Chemical
Wenjian Cai, Shuyan Wang, Xiaoxue Jiang, Hassan Muhammad, Huilin Lu
Summary: This study simulated the mixing process of SC and LC binary mixture in a supercritical carbon dioxide fluidized bed using unequal granular temperature-based kinetic theory, and identified the mixing/segregation tendency between the two components based on synergy angle.
Article
Engineering, Chemical
Guoqing Lian, Wenqi Zhong
Summary: The CFD-DEM coupled with heat transfer and chemical reaction sub-models was used to simulate oxy-char combustion in a fluidized bed. The study investigated the thermal conversion characteristics of char, including reaction rate, combustion temperature, and heat transfer. Results showed that convection heat and radiation heat were the main contributors, while conduction heat played an insignificant role.
Article
Engineering, Chemical
Carlin Leung, Justin Adler, Nina Shapley, Timothy A. G. Langrish, Benjamin J. Glasser
Summary: This article applies a mathematical model to predict drying curves and rates in a fluidized bed dryer and compares the model results with experimental data. The model shows good agreement with experimental drying curves and successfully predicts the drying time for non-fluidized cases. Furthermore, the model predicts drying curves for both single and multiple changes in process parameters.
CHEMICAL ENGINEERING SCIENCE
(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)
