Article
Thermodynamics
Yiqing Wang, Wang Han, Antonio Attili, Zheng Chen
Summary: This study investigates the impact of soot formation on flame speed measurements under fuel-rich conditions by simulating one-dimensional outwardly propagating spherical flames. The results show that soot dynamics and morphology are highly sensitive to changes in equivalence ratio and flame radius.
COMBUSTION AND FLAME
(2022)
Article
Mathematics
Sergey M. Frolov, Vladislav S. Ivanov, Fedor S. Frolov, Pavel A. Vlasov, Richard Axelbaum, Phillip H. Irace, Grigoriy Yablonsky, Kendyl Waddell
Summary: This article presents the results of the joint American-Russian space experiment conducted on the International Space Station, which aimed to study the mechanisms of soot formation in a spherical diffusion flame under microgravity conditions. The study found that soot formation was mainly concentrated in the region where the local C/O atomic ratio was between 0.32 and 0.44, and the local temperature was greater than 1300-1500 K.
Article
Thermodynamics
A. V. Drakon, E. V. Gurentsov, A. V. Eremin, R. N. Kolotushkin, E. S. Khodyko, H. Jander
Summary: This paper presents the experimental and calculated results of investigating the soot formation in a premixed ethylene/air flame with the addition of dimethyl ether. The experimental results show that the addition of dimethyl ether affects the soot volume fraction. The kinetic modeling and analysis reveal the importance of benzene formation as a precursor to soot.
COMBUSTION AND FLAME
(2022)
Article
Energy & Fuels
Andisheh Khanehzar, Francisco Cepeda, Seth B. Dworkin
Summary: The study investigates the effects of adding different percentages of hydrogen and nitrogen to the fuel in ethylene/air diffusion flames on soot formation and flame characteristics. Results show that blending hydrogen and nitrogen into the fuel decreases soot volume fraction and radiation. The dilution effect of hydrogen has the most significant influence on soot formation/oxidation reaction rates among the various effects.
Article
Energy & Fuels
Yu Yang, Shu Zheng, Yuzhen He, Hao Liu, Ran Sui, Qiang Lu
Summary: The soot formation in a co-flow diffusion ethylene flame with the addition of CO2 was investigated numerically and experimentally in this study. The effects of different CO2 addition ways on soot inception, soot condensation, and oxidation processes were quantitatively analyzed. The results showed that CO2-F/O was the most effective in inhibiting soot formation, followed by CO2-O and CO2-F.
Article
Thermodynamics
Marek Serwin, Ahmet E. Karatas
Summary: An experimental study investigated the effects of flame oscillations on soot concentration and flame temperature in ethylene co-flow laminar diffusion flames. The researchers mechanically induced flame oscillations using a computer-controlled linear stage, and found that the oscillation type changed from flickering to tip-clipping above 10 Hz at a 1 mm peak-to-peak oscillation amplitude. The time-averaged soot concentration increased initially with small oscillation frequencies and amplitudes, but then decreased as the oscillation intensity was increased.
PROCEEDINGS OF THE COMBUSTION INSTITUTE
(2023)
Article
Chemistry, Applied
Anurag Dahiya, Hairong Tao, Chih-Chia Lin, Kuang C. Lin
Summary: This study aims to develop a skeletal mechanism with extended predictive capability and lowered computational cost for computational fluid dynamics modeling of ethylene combustion. The newly assembled and refined kinetic mechanism is minimized without empirically adjusting kinetic parameters. It accurately predicts species formation and experimental data in both premixed and nonpremixed flames, and unveils the correlation between reaction pathways and intermediate formation in ethylene oxidation at the low temperature regime.
FUEL PROCESSING TECHNOLOGY
(2023)
Article
Chemistry, Physical
Xiaotong Mi, Ahmad Saylam, Torsten Endres, Christof Schulz, Thomas Dreier
Summary: The formation of soot at near-threshold conditions in laminar premixed ethylene/air flames (with ethene as a fuel, phi around 1.90) at pressures from 1 to 10 bar was studied. It was found that the soot volume fraction scales with pressure in a power-law function, the soot diameter increases with pressure and equivalence ratio, and the reliability of TiRe-LII particle diameter determination under near-threshold conditions is good.
Article
Energy & Fuels
Luoxi Wang, Fei Ren, Xiaogang Cheng, Zhan Gao, Ang Li, Lei Zhu, Zhen Huang
Summary: This study investigates the effects of ammonia addition on the morphology evolution, nanostructure, and oxidation reactivity of soot particles in ethylene laminar diffusion flame. Soot sampling was conducted using a thermophoresis probe, and the morphological evolution was observed using transmission electron microscopy. High resolution transmission electron microscopy, Raman spectroscopy, and thermogravimetric analysis were employed to study the nanostructure and oxidation reactivity of the soot particles. The results reveal that ammonia addition inhibits the surface growth of primary soot particles, reduces the average particle size, and greatly reduces the condensation and agglomeration of soot particles.
Article
Thermodynamics
J. Moran, A. Poux, F. Cepeda, F. Escudero, A. Fuentes, L. Gallen, E. Riber, B. Cuenot, J. Yon
Summary: The macroscopic simulation of soot production in flames often assumes spherical particles or uses ad-hoc formulas, while numerically simulated aggregates can be generated at the nanoscopic scale through DEM simulations. This study combines these approaches to investigate the detailed morphology of soot in a diffusion flame. The proposed multi-scale approach reveals larger and more compact aggregates near the wings of the flame.
COMBUSTION AND FLAME
(2023)
Article
Energy & Fuels
Hong-Quan Do, Luc-Sy Tran, Laurent Gasnot, Xavier Mercier, Abderrahman El Bakali
Summary: Experimental investigation on methane premixed flames with and without hydrogen showed that the introduction of hydrogen has insignificant impact on the maximum mole fractions of small species in the flame.
Article
Energy & Fuels
Samuel Cowart, Gautham Krishnamoorthy
Summary: A methodology for modeling soot production in ethylene-O-2/CO2 diffusion flames based on a skeletal reaction mechanism and the soot nucleation parameter C-alpha showed good agreement with measurements. The study revealed that in-flame radiation is influenced by gas-radiative property models, while the overall radiant fraction is impacted by the choice of soot radiative property model.
Article
Thermodynamics
Marek Serwin, Ahmet E. Karata
Summary: A simple and cost-effective technique for temperature and soot volume fraction measurement has been developed based on a three-sensor CMOS camera. The accuracy of the measurements was improved by using a telecentric imaging lens. Good agreement for temperature measurements and excellent agreement for soot concentration measurements were shown in comparison with previous results.
EXPERIMENTAL THERMAL AND FLUID SCIENCE
(2022)
Article
Thermodynamics
Francisco Cepeda, Rodrigo Demarco, Felipe Escudero, Juan Jose Cruz Villanueva, Gonzalo Carvajal, Andres Fuentes
Summary: This study investigated the relationship between soot concentration and temperature, and provided new data for time-dependent numerical simulations by measuring local radiative heat flux on transient laminar flames. Results showed that forced condition significantly changed soot production, temperature distribution, and radiative properties, enhancing flame radiation.
COMBUSTION AND FLAME
(2022)
Article
Chemistry, Applied
Xiaokang Nie, Jiawei Qi, Shunjie Feng, Ya Liu, Bingbing Qiu, Huaqiang Chu
Summary: In this study, the mixture of n-heptane and toluene was used as a surrogate fuel for diesel. The flame morphology, particle size, and soot deposition of three kinds of fuel blends were investigated using various microscopy techniques. The results showed that the addition of toluene promoted the formation of soot and influenced its morphology and structure.
FUEL PROCESSING TECHNOLOGY
(2022)
Article
Thermodynamics
Yu Yang, Shu Zheng, Ran Sui, Qiang Lu
Summary: Ammonia (NH3) is being studied as a potential alternative to carbon-containing fuels for reducing CO2 and soot emissions, but co-burning with hydrocarbons poses challenges such as increased NO emissions. This study investigates the suppression/formation mechanisms of soot and NO during the co-burning of NH3 and hydrocarbons, using numerical simulations and a detailed chemical mechanism.
COMBUSTION AND FLAME
(2023)
Article
Energy & Fuels
Ji Liu, Wei Zhao, Shuang-wei Yang, Bin Hu, Yuan-gu Xia, Yang-wen Wu, Wen-luan Xie, Qiang Lu
Summary: The inherent metal ions in food wastes have significant impacts on the release of NOx during incineration, but the mechanism behind their catalytic effects remains unclear. This study investigated the effects of Na+ and K+ on the production of NOx precursors. The results showed that Na+ and K+ have different catalytic effects, and can change the rate-determining steps of NOx precursor formation. NH3 formation is the most competitive pathway under the catalysis of Na+ and K+.
Article
Energy & Fuels
Ming-xin Xu, Ping-xin Zhang, Hai-wen Ji, Ya-chang Wu, Zi-shu Liu, Qiang Lu
Summary: The study examined the effects of acid or basic oxides and their interactions on ash melting in oxy-biomass combustion. A regression model revealed that the A/B ratio had a significant impact on softening temperature (ST). By modifying the Si/Al and A/B ratios, the ash fusion temperatures (AFTs) were increased and ash slagging was effectively alleviated during combustion.
Article
Energy & Fuels
Shu Zheng, Weiguang Cai, Bing Liu, Shaohua Zhu, Bo Zhou, Ran Sui, Qiang Lu
Summary: This study reports the first measurements of two-dimensional distributions of flame temperatures in a Rocket-Based Combined Cycle (RBCC) combustion chamber using a multispectral imaging technique. The relationship between the multispectral radiation intensity images and the flame temperature distributions was established. The experimental results showed that laser-induced plasma (LIP) and plasma jet (PJ) torches had positive effects on combustion stabilization, with LIP having a better effect on combustion enhancement. The study also revealed the formation of a recirculation zone inside a cavity and the location where fuel and inflow were most fully mixed.
Article
Agricultural Engineering
Bo Wang, Kai Li, Cheng-bo Zhang, Bin Hu, Yan-qin Huang, Ti-peng Wang, Qiang Lu
Summary: This study aimed to improve the production efficiency of levoglucosenone (LGO) from cellulose catalytic pyrolysis by optimizing its ultrastructure. Cellulose was pretreated with Na2CO3 solutions of different concentrations and Amberlyst-15 (A-15) at different temperatures. The effects of pretreatment on cellulose ultrastructure, particularly the degree of polymerization (DP) and crystallinity index (CrI), were investigated. The catalytic pyrolysis experiments revealed that Na2CO3 pretreatment significantly reduced CrI of cellulose and slightly decreased DP. Low Na2CO3 concentration promoted LGO generation by reducing CrI, while high concentration hindered LGO formation due to the transformation of cellulose I & beta; to II. A-15 pretreatment increased CrI and decreased DP with increasing temperature, leading to a gradual decrease in LGO yield. The cellulose pretreated with 1% Na2CO3 solution exhibited the highest LGO yield of 19.76 wt.%, higher than that of raw cellulose (18.04 wt.%), with lower pyrolysis temperature and catalyst dosage.
INDUSTRIAL CROPS AND PRODUCTS
(2023)
Article
Chemistry, Analytical
Ji Liu, Hao Fu, Guan-zheng Zhou, Zi-teng Guo, Bin Hu, Yang Li, Xiao-yan Jiang, Qiang Lu
Summary: The safe and efficient utilization of waste medical masks has attracted worldwide attention. Fast pyrolysis with the catalysis of zeolites can provide a promising route for the production of value-added aromatic hydrocarbons from waste medical masks. HZSM-5 catalysts were employed and modified by metal loading and alkali treatment, resulting in high yields of aromatics from the pyrolysis of mask filters.
JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
(2023)
Article
Green & Sustainable Science & Technology
Shu Zheng, Hao Liu, Yuzhen He, Yu Yang, Ran Sui, Qiang Lu
Summary: Biomass energy is gaining attention due to its zero carbon emissions and abundant reserves. Pyrolysis is found to be an efficient and clean method for biomass energy conversion. However, the effects of H2O content and radiation reabsorption in biomass pyrolysis gas combustion have not been thoroughly investigated.
Article
Chemistry, Physical
Hao-Ze Chen, Ji Liu, Teng-Ge Mi, Yang-Wen Wu, Bin Hu, Xin-Yue Zhou, Bing Zhang, Qiang Lu
Summary: Cu-based catalysts are efficient for furfural (FF) hydrogenation. The doping of Ni can enhance the catalyst's adsorption capacity and H2 dissociation ability, leading to improved hydrogenation activity.
APPLIED SURFACE SCIENCE
(2023)
Article
Engineering, Environmental
Wen-luan Xie, Bin Hu, Yuan-gu Xia, Guo-yong Song, Ji Liu, Ying Liu, Qiang Lu
Summary: The bimolecular concerted interaction mechanism, namely the tautomer-assisted hydrogen transfer (AHT) mechanism, was found to play a vital role in lignin pyrolysis. The tautomer-AHT mechanism promotes the breakage of the beta-O-4 linkage in lignin by utilizing the saturated and unsaturated groups of the tautomer for hydrogen transfer processes. This mechanism provides a theoretical foundation for exploring complex interactions in lignin pyrolysis.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Thermodynamics
Shi-guan Yang, Jia-le Zhou, Zhuang Hu, Xin-yue Zhou, Qi Cai, Jin-heng Xie, Yang-wen Wu, Qiang Lu
Summary: Due to the shortage of fossil energy, pyrolysis is a promising method for utilizing biomass resources. This paper proposes a low-carbon decision-making framework for biomass pyrolysis project site selection. A complete criteria system, incorporating the concept of low-carbon development, is established and an improved TODIM method is used to determine the best option. The study provides insightful theoretical basis for site selection of biomass pyrolysis projects.
Article
Energy & Fuels
Yang-wen Wu, Yi-fei Yu, Qi Cai, Hai-yuan Zhao, Rong Guo, Jia-le Zhou, Zhuang Hu, Xin-yue Zhou, Li Zhao, Qiang Lu
Summary: By modifying a commercial SCR catalyst with FeO x , the synergistic removal activities for NO and dioxins were improved. The addition of FeO x increased the specific surface area and pore volume of the catalyst, improving the dispersion of vanadium species. The enhanced surface acid centers and redox capacity of the catalyst further increased the adsorption and destruction efficiencies of both nitric oxide and dioxins.
Article
Polymer Science
Shi-yu Feng, Kai Li, Zhu-yu Li, Dong-hong Nan, Yan-qin Huang, Ji Liu, Qiang Lu
Summary: A green method for the sustainable utilization of waste polycarbonate (PC) was developed, involving NaOH solution-assisted pyrolysis to produce phenolic compounds and supercapacitor material. By adjusting NaOH concentration and pyrolytic temperature, the yields of phenol and 4-isopropenylphenol (IPP) reached up to 35.3 wt% and 29.9 wt% respectively at 600 degrees C and NaOH concentration of 0.5 mol/L, significantly higher than those from pure PC pyrolysis. Additionally, the pyrolytic solid residue could be directly activated at high temperature to prepare activated carbon, which exhibited an outstanding specific gravimetric capacitance of 182.1 F/g at 1 A/g.
POLYMER DEGRADATION AND STABILITY
(2023)
Article
Thermodynamics
Ming-xin Xu, Xin-yu Zhang, Ping-xin Zhang, Jin-yi Di, Hai-wen Ji, Xiang-xi Meng, Qiang Lu
Summary: In this study, the interactive effects of reaction temperature, O2 concentration, and recycled SO2 on ash slagging in oxy-biomass combustion were systematically explored. The results showed that O2 concentration had the most significant influence on ash softening temperature (ST), followed by reaction temperature and recycled SO2. Increasing O2 concentration amplified the effects of reaction temperature on ST, and O2 also had a dominant influence on the ash slagging index (RAFI), which was weakened with increasing reaction temperature or SO2 concentration. A novel method of ternary phase diagram was proposed for predicting ST and RAFI simultaneously.
Article
Energy & Fuels
Hao-ze Chen, Ji Liu, Wen-tao Li, Bin Hu, Xin-ru Liu, Yang-wen Wu, Bing Zhang, Qiang Lu
Summary: A study was conducted to investigate the decarbonylation mechanism of furfural (FF) over single-site and multi-site Ni/MgO surfaces. It was found that Ni doping can modify the electronic density of MgO, leading to favorable electronic configurations for FF adsorption. The study also revealed that the multi-site Ni/MgO catalyst has better catalytic activity in the C-C bond-breaking-induced pathway. In addition, potential decarbonylation catalysts doped by diverse metals over the MgO surface were examined, and Ni/MgO showed excellent decarbonylation performance comparable to Pt/MgO catalyst.
Article
Energy & Fuels
Ming-xin Xu, Zi-shu Liu, Xin-yu Zhang, Jin-yi Di, Xiang -xi Meng, Li Zhao, Qiang Lu
Summary: In this study, a TiO2-SiO2 composite-supported Ni-based catalyst was prepared for catalytic steam reforming of biomass gasification tar. The addition of SiO2 to TiO2 improved the conversion of benzene and increased the yield of H-2 in the syngas, with promising thermal stability and anti-carbon deposition capacity.
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)