Article
Thermodynamics
Chaouki Ghenai, Ruqiya Abdullah Farah, Ola Al Saidi, Ayesha Al Suwaidi, Oussama Rejeb, Abrar Inayat
Summary: This study focuses on optimizing a pyrolysis reactor powered by a solar parabolic trough collector to maximize the production of high-quality biofuels. By using modeling and simulation analyses, the effects of different input factors on the reactor's performance were determined. The results show the benefits of using solar thermal energy for biomass conversion to renewable fuels.
CASE STUDIES IN THERMAL ENGINEERING
(2022)
Article
Engineering, Environmental
Tian Chang, Zhenxing Shen, Chuanlong Ma, Jiaqi Lu, Yu Huang, Savita K. P. Veerapandian, Nathalie De Geyter, Rino Morent
Summary: The study developed a non-thermal plasma system incorporated with MnOx-Fe2O3 catalyst for efficient formaldehyde removal. The results showed that discharge power had the greatest impact on removal efficiency, while the Fe/Mn molar ratio had the least influence. Factors such as the amount of adsorbed oxygen species, reducibility, and specific surface area of the catalyst were found to influence catalytic performance significantly.
JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING
(2021)
Article
Thermodynamics
Chunyu Liu, Haibin Yang
Summary: This paper focuses on the numerical investigation of a concrete thermal energy storage system using air as heat transfer fluid. Response surface models were established to analyze the effects of design parameters on performance, with velocity being the most important factor affecting charging time and efficiency. Interaction between parameters also plays a crucial role in performance indices.
APPLIED THERMAL ENGINEERING
(2022)
Article
Engineering, Multidisciplinary
Chuan Wang, Yulong Yao, Yang Yang, Xionghuan Chen, Hui Wang, Jie Ge, Weidong Cao, Qiqi Zhang
Summary: In this study, a hydraulic loss model for centrifugal pump impellers is established to predict the efficiency of centrifugal pumps. The functional relationship between impeller hydraulic loss and hydraulic efficiency is constructed, and the main dimensions of the impeller are calculated using the velocity coefficient method. Response surface analysis is then used to solve the relationship between hydraulic efficiency and dependent variables, and the accuracy of the predictions is verified through numerical simulation. The study provides a new direction for the hydraulic design of high specific speed centrifugal pumps to achieve more accurate predictions of efficiency.
ENGINEERING APPLICATIONS OF COMPUTATIONAL FLUID MECHANICS
(2023)
Article
Thermodynamics
Qiang Xu, Yongshuai Zhu, Haozu Zhou, Yonglu She, Liejin Guo
Summary: Gas-liquid two-phase jet condensation is highly efficient in heat and mass transfer, making it crucial for the optimization design and safe operation of industrial processes. In this study, a numerical simulation method was developed to investigate steam-water two-phase jet condensation, focusing on the shape of the steam plume, pressure and velocity distribution, and heat and mass transfer at the two-phase interface. The results showed that as the steam mass flux increased, the steam plume lengthened and transformed from a cone to a cylinder-cone shape. The heat transfer coefficients varied from 1.71 MW/m(2) K to 3.51 MW/m(2) K based on the interfacial area of the steam plume, and from 2398.80 MW/m(3) K to 5040.07 MW/m(3) K based on the volume of the two-phase region.
APPLIED THERMAL ENGINEERING
(2022)
Article
Multidisciplinary Sciences
Nadia Hamzawy, Tamer S. Mahmoud, Iman El-Mahallawi, Mahmoud Khedr, Tarek Khalifa
Summary: Thermal drilling is a chip-less hole-forming process affected by rotational speed, feed rate, and cone angle. This study investigates the effect of variations in friction drilling parameters on the surface roughness values and dimensions of a thermally induced bushing. Response surface methodology was used to optimize the drilling parameters, and the experimental results agree with the presented models. The optimal parameters for the lowest surface roughness value are a rotational speed of 1250 rpm, a feed rate of 200 mm/min, and a cone angle of 45 degrees.
ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING
(2023)
Article
Engineering, Environmental
Azmatullah Noor, Wahid Ali, Tarique Ahmad, Md. Tabish Noori, Shams Anwar, Mohammad Ehtisham Khan, Augustine Chioma Affam, Abdullateef H. Bashiri, Waleed Zakri, Ahmad Hussaini Jagaba
Summary: This study investigated the treatment of petrochemical wastewater using different biocarriers in an integrated activated sludge system. The results showed that the 3D printed biocarrier performed better in organic and nutrient removal. The study also revealed a higher abundance of beneficial bacteria in the 3D printed biocarrier.
JOURNAL OF WATER PROCESS ENGINEERING
(2023)
Article
Energy & Fuels
Kadir Gelis, Ali Naci Celik, Kadir Ozbek, Omer Ozyurt
Summary: This study investigated the impact of nanofluids on the electrical and thermal efficiency of photovoltaic thermal systems (PVT) using the Response Surface Methodology (RSM). The experimental results showed that the flow rate, nanofluid volumetric concentration, and solar radiation were the most influential parameters affecting the thermal and electrical efficiency. The mathematical models developed based on the experimental outcomes successfully verified the performance of the PVT system in terms of electrical and thermal efficiencies.
Article
Water Resources
J. Fernandez-Galvez, J. A. P. Pollacco, L. Lilburne, S. McNeill, S. Carrick, L. Lassabatere, R. Angulo-Jaramillo
Summary: This study focuses on obtaining a unique set of physical bimodal soil Kosugi hydraulic parameters from inverse modeling, by deriving a procedure to reduce the number of optimized parameters and dynamically constraining the hydraulic parameters. The method successfully reduces the parameter count and constraints the hydraulic parameters without compromising the fit of theta(psi) and K(theta) functions, resulting in more physical hydraulic parameters.
ADVANCES IN WATER RESOURCES
(2021)
Article
Thermodynamics
Shaojie Zhang, Lin Lu, Qiuwang Wang
Summary: The study showed that the full-length SRTTs can start rotating at a lower Reynolds number and larger length ratios significantly increase the rotational speed, providing higher friction factor, thermal performance factor and Nussle number. Moreover, associated correlations regarding the length ratio to predict the thermal performance were derived.
INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER
(2021)
Article
Green & Sustainable Science & Technology
Hitesh Khurana, Rudrodip Majumdar, Sandip K. Saha
Summary: This study developed a two-dimensional axisymmetric numerical model to simulate the operation of a standalone thermal energy storage (TES) system and formed an effective prediction model based on experimental data. The results showed the impact of thermal stratification on the efficiency and thermodynamic quality of the storage system. A prediction model was successfully developed using response surface methodology and analysis of variance, and various plots were created for model analysis.
Article
Materials Science, Composites
Mohammad Mansourian-Tabaei, Shan Jiang, Hunain Alkhateb, Alexander M. Lopez, Ahmed Al-Ostaz, Sasan Nouranian
Summary: In this study, the effects of graphene content, temperature, and graphene layer structure on the thermal conductivities of PEI/Gr nanocomposites were systematically investigated using an I-optimal response surface model. The results showed that the graphene content had a more pronounced effect on thermal conductivity in the PEI/Gr nanocomposite with a five-layer graphene structure. The temperature had the largest effect on thermal conductivity, followed by the graphene layer structure. However, significant interactions were observed between these factors. The study provided valuable insights into the interactions between the investigated factors.
POLYMER COMPOSITES
(2023)
Article
Polymer Science
Heitor Luiz Ornaghi Jr, Francisco Maciel Monticeli, Roberta Motta Neves, Lucas Dall Agnol, Otavio Bianchi
Summary: In this study, a thermogravimetric (TG) model of a renewable polyurethane-urea was developed using response surface methodology (RSM). The predicted TG curves showed similar curve format, but different kinetic results compared to the experimental ones. The correlation analysis indicated that the mass loss had no significant influence on the other tested parameters.
Article
Mathematics
Zicheng Xin, Jiankun Sun, Jiangshan Zhang, Bingchang He, Junguo Zhang, Qing Liu
Summary: By conducting water model experiments, this study optimized the mixing time and slag eye area in the ladle furnace refining process using various methods. The optimal parameter combination can meet the requirements of the LF refining process and has been validated through experiments.
Article
Chemistry, Multidisciplinary
Yanpeng Zhu, Qingliang Zeng, Lirong Wan, Zhe Li, Dejian Ma
Summary: This study investigates the impact response of the tail beam jack in top coal caving mining using a bidirectional fluid-structure coupling model. The conclusions reveal that the stress and strain in the rodless cavity are larger, making it more susceptible to damage. The hydraulic pressure in the jack cavity has a vertical layered distribution, and the flow velocity streamlines exhibit spiral shapes. The impact response of the jack is more sensitive and stronger in motion compared to the stationary state. The integration of pressure and velocity signals provides effective identification of coal rock collapse. The findings contribute to the understanding of the jack's structural design and failure prevention.
Article
Thermodynamics
Peng Yang, Ying-Wen Liu, Go-Yu Zhong
APPLIED THERMAL ENGINEERING
(2016)
Article
Thermodynamics
Ge-Yu Zhong, Peng-Fan Chen, Fa-Zhu Liu, Ying-Wen Liu
Summary: This study focuses on the unsteady characteristics of heat transfer process in wavy channels under oscillating flow, with findings on the factors influencing heat transfer performance.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2022)
Article
Thermodynamics
Pengfan Chen, Geyu Zhong, Yafeng Niu, Yingwen Liu
Summary: In this paper, a TD-Sage model is proposed for a beta-type free piston Stirling engine, and the performance of the engine is improved using the response surface methodology and desirability approach. The optimal design parameters and maximum output power are obtained through the analysis of factors and available energy loss analysis.
Article
Physics, Fluids & Plasmas
Geyu Zhong, Yingwen Liu, Xiaofeng Guo, Laurent Royon, Philippe Brunet
Summary: In this paper, the flow structure generated by low-frequency forcing around a sharp tip is studied using direct numerical simulations. The periodic and steady responses are extracted within a large span of amplitude of vibrations. When the amplitude is smaller than the tip radius of curvature, the flow structure is similar to that observed at higher frequencies, with an intense central jet and a quadratic dependence for the streaming velocity with the oscillating velocity. At higher amplitudes, this scaling no longer holds and the streaming flow pattern loses its left-right symmetry. The mechanisms of the instability are analyzed from the careful examination of the instationary flow fields, and possible mechanisms involving the coupling between the streaming jet and instationary vorticity are proposed.
Article
Thermodynamics
Geyu Zhong, Chuanyu Zhang, Xiaofeng Guo, Peng Yang, Yingwen Liu
Summary: This research focuses on the formation and transmission process of oscillatory vortices in oscillatory flow driven by the periodical reverse of flow orientation. It explores the spatial-temporal relationships between fluid dynamics and energy transmission, providing insights into the underlying mechanisms of heat transfer enhancement in oscillating flow.
ASME JOURNAL OF HEAT AND MASS TRANSFER
(2023)
Article
Thermodynamics
Zunhua Zhang, Pengpeng Jia, Geyu Zhong, Junjie Liang, Gesheng Li
APPLIED THERMAL ENGINEERING
(2017)
Article
Thermodynamics
Mahsa Taghavi, Swapnil Sharma, Vemuri Balakotaiah
Summary: This study investigates the natural convection effects in the insulation layers of spherical storage tanks and their impact on the tanks' performance. The permeability and Rayleigh number of the insulation material are considered as key factors. The results show that as the Rayleigh number increases, new convective cells emerge and cause the cold boundary to approach the external hot boundary. In the case of large temperature differences, multiple solutions may coexist.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Jinyang Xu, Fangjun Hong, Chaoyang Zhang
Summary: This study introduces a self-induced jet impingement device for enhancing pool boiling performance in high power electronic cooling. Through visualization and parametric investigations, the effects of this device on pool boiling performance are studied, revealing the promotion of additional liquid supply and vapor exhausting. The flow rate of the liquid jet is found to positively impact boiling performance.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Wenchao Ke, Yuan Liu, Fissha Biruke Teshome, Zhi Zeng
Summary: Underwater wet laser welding (UWLW) is a promising and labor-saving repair technique. A thermal multi-phase flow model was developed to study the heat transfer, fluid dynamics, and phase transitions during UWLW. The results show that UWLW creates a water keyhole, making the welding environment similar to in air laser welding.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Xingrong Lian, Lin Tian, Zengyao Li, Xinpeng Zhao
Summary: This study investigates the heat transfer mechanisms in natural fiber-derived porous structures and finds that thermal radiation has a significant impact on the thermal conductivity in low-density regions, while natural convection rarely occurs. Insulation materials derived from micron-sized natural fibers can achieve minimum thermal conductivity at specific densities. Strategies to lower the thermal conductivity include increasing porosity and incorporating nanoscale pores using nanosize fibers.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Yasir A. Malik, Kilian Koebschall, Stephan Bansmer, Cameron Tropea, Jeanette Hussong, Philippe Villedieu
Summary: Ice crystal icing is a significant hazard in aviation, and accurate modeling of sticking efficiency is essential. In this study, icing wind tunnel experiments were conducted to quantify the volumetric liquid water fraction, sticking efficiency, and maximum thickness of ice layers. Two measurement techniques, calorimetry and capacitive measurements, were used to measure the liquid water content and distribution in the ice layers. The experiments showed that increasing wet bulb temperatures and substrate heat flux significantly increased sticking efficiency and maximum ice layer thickness.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Jinqi Hu, Tongtong Geng, Kun Wang, Yuanhong Fan, Chunhua Min, Hsien Chin Su
Summary: This study experimentally examined the heat dissipation of vibrating fans and demonstrated its inherent mechanism through numerical simulation. The results showed that the flow fields induced by the vibrating blades exhibited pulsating features and formed large-scale and small-scale vortical structures, significantly improving heat dissipation. The study also identified the impacts of different blade structures and developed a trapezoidal-folding blade, which effectively reduced the maximum temperature of the heat source and alleviated high-temperature failure crisis.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Dan-Dan Su, Xiao-Bin Li, Hong-Na Zhang, Feng-Chen Li
Summary: The boiling heat transfer of low-boiling-point working fluid is a common heat dissipation technology in electronic equipment cooling. This study analyzed the interfacial boiling behavior of R134a under different conditions and found that factors such as the initial thickness of the liquid film, solid-liquid interaction force, and initial temperature significantly affect the boiling mode and thermal resistance.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Jinyi Wu, Dongke Sun, Wei Chen, Zhenhua Chai
Summary: A unified lattice Boltzmann-phase field scheme is proposed to simulate dendrite growth of binary alloys in the presence of melt convection. The effects of various factors on the growth are investigated numerically, and the model is validated through comparisons and examinations.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Shaokun Ge, Ya Ni, Fubao Zhou, Wangzhaonan Shen, Jia Li, Fengqi Guo, Bobo Shi
Summary: This study investigated the temperature distribution of main cables in a suspension bridge during fire scenarios and proposed a prediction model for the maximum temperature of cables in different lane fires. The results showed that vehicle fires in the emergency lane posed a greater thermal threat to the cables.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Shuang-Ying Wu, Shi-Yao Zhou, Lan Xiao, Jia Luo
Summary: This paper investigates the two-phase flow and heat transfer characteristics of low-velocity jet impacting on a cylindrical surface. The study reveals that the heat transfer regimes are non-phase transition and nucleate boiling with the increase of heat transfer rate. The effects of jet impact height and outlet velocity on local surface temperatures are pronounced at the non-phase transition stage. The growth rates of heat transfer rate and liquid loss rate increase significantly from the non-phase transition to nucleate boiling stage.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Emad Hasani Malekshah, Wlodzimierz Wlodzimierz, Miros law Majkut
Summary: Cavitation has significant practical importance and can be controlled by air injection. This study investigates the natural to ventilated cavitation process around a hydrofoil through numerical and experimental methods. The results show that the location and rate of air injection have a meaningful impact on the characteristics of cavitation.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Feriel Yahiat, Pascale Bouvier, Antoine Beauvillier, Serge Russeil, Christophe Andre, Daniel Bougeard
Summary: This study explores the enhancement of mixing performance in laminar flow equipment by investigating the generation of chaotic advection using wall deformations in annular geometries. The findings demonstrate that the combined geometry can achieve perfect mixing at various Reynolds numbers.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Hui He, Ning Lyu, Caihua Liang, Feng Wang, Xiaosong Zhang
Summary: This study investigates the condensation, frosting, and defrosting processes on superhydrophobic surfaces with millimeter-scale structures. The results reveal that the structures can influence the growth and removal of frost crystals, with the bottom grooves creating a frost-free zone and conical edges promoting higher frost crystal heights. Two effective methods for defrosting are observed: hand-lifting the groove and airfoil retraction contraction on protruding structures. This research provides valuable insights into frost formation and defrosting on millimeter-structured superhydrophobic surfaces, with potential applications in anti-frost engineering.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Thiwanka Arepolage, Christophe Verdy, Thibaut Sylvestre, Aymeric Leray, Sebastien Euphrasie
Summary: This study developed two thermal concentrators, one with a 2D design of uniform thickness and another with a 3D design, using the coordinate transformation technique and metamaterials. By structuring the thermal conductor, the desired local density-heat capacity product and anisotropic thermal conductivities were achieved. The homogenized thermal conductivities were obtained from finite element simulations and cylindrical symmetry consideration. A 3D concentrator was fabricated using 3D metal printing and characterized using a thermal camera. Compared to devices that solely consider anisotropic conductivities, the time evolution characteristics of the metadevice designed with coordinate transformation were closer to those of an ideal concentrator.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
Article
Thermodynamics
Liangyuan Cheng, Qingyang Wang, Jinliang Xu
Summary: In this study, we investigated the supercritical heat transfer of CO2 in a horizontal tube with a diameter of 10.0 mm, covering a wide range of pressures, mass fluxes, and heat fluxes. The study revealed a non-monotonic increase in wall temperatures along the flow direction and observed both positive and negative wall temperature differences between the bottom and top tube. The findings were explained by the thermal conduction in the solid wall interacting with the stratified-wavy flow in the tube.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2024)
