Article
Thermodynamics
Xu Wang, Huazhao Xu, Jianhua Wang, Wei Song, Lei Wang
Summary: This study investigated the internal cooling characteristics of turbine blades in a realistic rib roughened two-pass channel and found that the type of wall boundary conditions had a significant impact on blade internal cooling performance, with blade rotation leading to a significant increase in heat transfer on the trailing surface.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2021)
Article
Thermodynamics
Xing Yang, Florian Seibold, Zhenping Feng, Bernhard Weigand
Summary: This study numerically investigates the flow and heat transfer behavior of swirl cooling in leaned, convergent tubes. The results show that the unsteady RANS method effectively captures the flow characteristics and heat transfer performance of swirling flows. The use of leaned tubes with Dean vortices improves heat transfer and reduces flow loss compared to straight tubes.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2022)
Article
Thermodynamics
Minho Bang, Seungyeong Choi, Seok Min Choi, Dong-Ho Rhee, Hee Koo Moon, Hyung Hee Cho
Summary: This study investigates the cooling effectiveness and flow characteristics of a turbine blade tip using a special slot cooling scheme. The slot cooling exhibits significantly enhanced cooling performance compared to cooling holes, providing better thermal durability and reliability for the blade tip.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2023)
Article
Energy & Fuels
Farah Nazifa Nourin, Brinn Leighton Blum, Ryoichi S. Amano
Summary: This investigation examines the rotational effect on gas turbine blade internal cooling. Experimental results show that rotation, dimple arrangement, and design have significant influences on heat transfer.
JOURNAL OF ENERGY RESOURCES TECHNOLOGY-TRANSACTIONS OF THE ASME
(2022)
Article
Thermodynamics
Jie Liu, Jiabing Wang, Kun Yang
Summary: In this study, a novel method of employing an inserted plate in turbine blades internal cooling channel is proposed for the first time, which enhances heat transfer and improves heat transfer uniformity by extending cold surfaces for radiation. The coupled convective and radiative heat transfer in the rotating channel is numerically explored, and the mechanisms of heat transfer enhancement are revealed and investigated. The results demonstrate that the novel model with the inserted plate parallel to the leading and trailing walls and considering radiation significantly increases the total Nusselt number ratio, performance evaluation criterion and reduces maximum and average temperature.
CASE STUDIES IN THERMAL ENGINEERING
(2023)
Article
Thermodynamics
Zhongyi Wang, Yue Yin, Yanhua Wang, Tao Sun, Yigang Luan
Summary: This article explores the similarity characteristics of cooling performance in gas turbine blades and the effects of geometric scaling factor. Numerical simulation and data fitting were used to find that the heat transfer performance and resistance performance increase exponentially with the increase of the scaling factor. Regression equations were established for accurate prediction in engineering applications.
APPLIED THERMAL ENGINEERING
(2022)
Article
Thermodynamics
Jinfu Chen, Ran Yao, Jianhua Wang, Xu Wang
Summary: In this study, a multi-objective optimization is conducted to enhance the internal cooling strategies of gas turbine blade leading edges by maximazing the heat transfer rate and minimizing the friction loss. By adopting advanced internal cooling concepts, four geometrical parameters are determined as design variables. Validated numerical simulations based on Reynolds Averaged Navier-Stokes equations are performed to generate accurate surrogate models. The optimized cooling strategies achieve significant heat transfer enhancement, reduced friction loss, and improved aerothermal efficiency compared to previous cooling methods.
INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER
(2023)
Article
Thermodynamics
Seok Min Choi, Hyun Goo Kwon, Seungyeong Choi, Minho Bang, Hee Koo Moon, Hyung Hee Cho
Summary: This study demonstrated that installing a delta-winglet-pair (DWP) in an internal cooling channel significantly enhances its cooling performance, especially under laminar and transitional flow conditions.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2021)
Article
Engineering, Mechanical
Shinjan Ghosh, Erik Fernandez, Jayanta Kapat
Summary: Topology optimization is used to manipulate flow geometries by adjusting the distribution of material blockage. This method has been applied to modify the geometric configuration of internal cooling ducts, resulting in improved heat transfer and reduced pressure drop. By optimizing the flow-path of serpentine channel and high aspect ratio rectangular ducts, the thermal performance efficiency has been increased.
JOURNAL OF MECHANICAL DESIGN
(2022)
Article
Chemistry, Multidisciplinary
Liang Xu, Qingyun Shen, Qicheng Ruan, Lei Xi, Jianmin Gao, Yunlong Li
Summary: This study introduces an integral optimization method for lattice cooling structures used at the trailing edge of turbine blades, which focuses on both heat transfer and mechanical performance, ultimately improving the lifespan of gas turbine blades.
APPLIED SCIENCES-BASEL
(2021)
Article
Chemistry, Multidisciplinary
Tao Xu, Dongbo Shi, Di Zhang, Yonghui Xie
Summary: This paper investigates the cooling channel considering the turning vane, variable cross-section characteristics, and rotation effect. The effects of different thickness guide vanes on the overall performance of the channel under stationary and rotating conditions are discussed and compared by numerical method. The result shows that the comprehensive performance of the variable cross-section serpentine channel can be greatly improved by arranging the turning vane structure with appropriate thickness.
APPLIED SCIENCES-BASEL
(2023)
Article
Thermodynamics
Mingeon Kim, Dong Hwan Shin, Jin Sub Kim, Bong Jae Lee, Jungho Lee
Summary: This study investigated the effectiveness of effusion and transpiration cooling for turbine blades, with experiments conducted in a high-temperature wind tunnel. The research found that transpiration cooling achieved 34% and 25% higher cooling effectiveness compared to effusion and internal cooling respectively.
APPLIED THERMAL ENGINEERING
(2021)
Article
Mechanics
C. T. Dinh, T. M. Nguyen, T. D. Vu, S. G. Park, Q. H. Nguyen
Summary: A new turbine blade rib configuration called the truncated-root rib was designed in this study to reduce the disadvantages of the traditional squared-rib and improve heat transfer performance. Numerical results showed that the heat transfer performance of the truncated-root rib configuration was greater than that of the squared-rib, with an increase in Nusselt number by 8.56% and a 39.24% higher thermal performance compared to the original rib shape.
Article
Thermodynamics
Guohua Zhang, Gongnan Xie, Sunden Bengt
Summary: This paper presents numerical simulations to investigate the mechanisms between film cooling and internal cooling, and analyzes the effects of different cooling channels and hole shapes on the cooling effectiveness and heat transfer performance. The results show that ribs and suction of film holes have different influences on the heat transfer performance in the internal cooling channel.
JOURNAL OF THERMAL SCIENCE
(2023)
Article
Thermodynamics
Inderjot Kaur, Youssef Aider, Karthik Nithyanandam, Prashant Singh
Summary: Gas turbine blade trailing edge cooling is a challenging task due to strict geometrical constraints and thermal stresses. Traditional pin-fin structures are commonly used for internal cooling, but lattice structures have shown better heat transfer performance. In this study, four different lattice unit cell topologies were additively manufactured in 420 Stainless Steel using Binder Jetting technology, and their heat transfer capabilities were evaluated.
APPLIED THERMAL ENGINEERING
(2022)
Article
Energy & Fuels
Young Seo Kim, Jin Young Jeong, Jae Su Kwak, Heeyoon Chung
Summary: An experimental study investigated the effects of fan-shaped film cooling hole arrangement and density ratio on heat transfer coefficient augmentation. Results showed that smaller hole pitch and higher blowing ratio lead to increased heat transfer coefficient augmentation, while row-to-row distance and hole arrangement have negligible effects on heat transfer coefficient.
Article
Engineering, Chemical
Min Seok Hur, Soo In Lee, Seong Won Moon, Tong Seop Kim, Jae Su Kwak, Dong Hyun Kim, Il Young Jung
Article
Engineering, Mechanical
Soo In Lee, Young Jun Kang, Woo Jun Kim, Jae Su Kwak, Tong Seop Kim, Dong Hyun Kim, Il Young Jung
Summary: The paper investigates the effects of geometric parameters on leakage flow through labyrinth seals in gas turbines. Experimental results show that the stepped labyrinth seal outperforms the straight seal in reducing leakage flow. Additionally, seal performance is better for cases with larger number of teeth, smaller tip clearance, and smaller tooth front angle.
JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY
(2021)
Article
Thermodynamics
Gi Mun Kim, Soo In Lee, Jin Young Jeong, Jae Su Kwak, Seokbeom Kim, Jung Uk Choi
Summary: This study experimentally investigated the effects of complex flow fields near gas turbine blades on film cooling effectiveness in the forward region of the shroud ring segment. The results indicated that the area-averaged film cooling effectiveness is more affected by the slot width than by the cooling hole configuration, and lower density ratio cases showed higher film cooling effectiveness compared to higher density ratio cases under the same cooling configuration.
JOURNAL OF THERMAL SCIENCE AND ENGINEERING APPLICATIONS
(2021)
Article
Energy & Fuels
Soo In Lee, Jin Young Jung, Yu Jin Song, Jae Su Kwak
Summary: The study experimentally investigated the effect of mainstream velocity on the optimization of a fan-shaped hole on a flat plate, showing that with an increase in blowing ratio, the hole exit area tended to increase. By comparing experimental data under different mainstream velocity conditions, the study revealed the impact of film-cooling hole shape parameters on film-cooling effectiveness.
Article
Energy & Fuels
Young Seok Kang, Dong-Ho Rhee, Yu Jin Song, Jae Su Kwak
Summary: The study utilized large eddy simulations to analyze film cooling hole arrays on a flat plate, finding that LES played a crucial role in resolving flow field issues. The results showed that LES could effectively predict the impact of upstream turbulence on turbulent boundary layer behavior, as well as film cooling flow behaviors and effectiveness distributions.
Article
Energy & Fuels
Jin Young Jeong, Woojun Kim, Jae Su Kwak, Byung Ju Lee, Jin Taek Chung
Summary: This study experimentally investigated the effects of cascade inlet velocity on the distribution and level of the heat transfer coefficient on a gas turbine blade tip. The results showed that as the inlet velocity increased, the heat transfer coefficient also increased. However, the impact of inlet velocity varied for different types of blade tips.
Article
Thermodynamics
Yu Jin Song, Sang Hyeon Park, Young Jun Kang, Jae Su Kwak
Summary: The study explored the effects of three trench configurations on the film cooling effectiveness of fan-shaped holes. Results showed that larger trench heights, smaller distances between hole exit and downstream sidewall, and smaller radii of curvature generally led to higher film cooling effectiveness. Additionally, higher density ratios resulted in higher overall film cooling effectiveness.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2021)
Article
Thermodynamics
Gi Mun Kim, Jae Su Kwak, Jung Uk Choi
Summary: The experimental study showed that installing a protrusion at the slot exit of inclined film cooling slots can significantly improve film cooling effectiveness, with greater improvement observed at higher blowing ratios for 45-degree slots. The height of the protrusion was found to have a greater impact on film cooling effectiveness than the width.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2022)
Article
Engineering, Mechanical
Young Jun Kang, Sang Hyeon Park, Jin Young Jeong, Gi Mun Kim, Jae Su Kwak
Summary: This study experimentally investigated the impact of five misalignment types on the film cooling effectiveness of laidback fan-shaped holes, revealing that lateral distance misalignment significantly decreases film cooling effectiveness, while vertical distance misalignment enhances it.
JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY
(2022)
Article
Energy & Fuels
Ye Rim Jo, Jin Young Jeong, Jae Su Kwak
Summary: This study experimentally investigated the effect of shape variables on the film cooling effectiveness of the compound angled asymmetric laidback fan shaped hole. The results showed that larger windward and leeward lateral expansion angles induced higher film cooling effectiveness, while the compound angle did not consistently affect the effectiveness.
Article
Engineering, Aerospace
Gi-Mun Kim, Jin-Young Jeong, Young-Jun Kang, Jae-Su Kwak
Summary: In this study, the aerodynamic loss of gas turbine vane with different trailing edge configurations was experimentally compared. Three cooling schemes (cutback slot, central injection slot, and pressure side hole) and three levels of trailing edge diameter were considered. The results showed that the distribution of total pressure loss was strongly influenced by cooling schemes. The total pressure loss increased as the trailing edge diameter increased, regardless of the cooling schemes.
Article
Engineering, Electrical & Electronic
Hyeok Je Kim, Young Jun Kang, Woojun Kim, Ye Rim Jo, Suhyeon Park, Jae Su Kwak
Summary: This study experimentally investigated the effects of geometry factors on the mass flow function of solid and honeycomb land labyrinth seals. The results showed that the number of fins and clearance significantly influenced the mass flow function, and the effects of the cell diameter and depth depended on other variables. Correlation equations were presented to represent these effects.
Article
Thermodynamics
Gi Mun Kim, Jin Young Jeong, Young Jun Kang, Jae Su Kwak
Summary: To achieve higher efficiency and performance, it is important to effectively inject purge flow to protect the endwall surface in a gas turbine. The present study investigated the effect of purge slot exit shape on the film cooling effectiveness (FCE) of a shroud surface. The results showed that wider slot width improved FCE, while the fillet radius at the windward side had a negative effect on FCE.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2024)
Proceedings Paper
Thermodynamics
Hyun Jae Seo, Sang Hyeon Park, Jae Su Kwak, Young Seok Kang
PROCEEDINGS OF THE ASME TURBO EXPO: TURBOMACHINERY TECHNICAL CONFERENCE AND EXPOSITION, 2019, VOL 5B
(2019)
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)