Article
Energy & Fuels
Christian A. Michelbach, Alison S. Tomlin
Summary: The study found good similarity between the gasoline surrogate and the reference gasoline in terms of combustion and knocking behavior, with notable differences observed in cyclic variability attributed to compositional differences. Furthermore, blending with iso-butanol was shown to improve performance compared to gasoline, with blends of 20-50% iso-butanol proving optimal for use in SI engines.
Review
Thermodynamics
Kristian Ronn, Andre Swarts, Vickey Kalaskar, Terry Alger, Rupali Tripathi, Juha Keskivali, Ossi Kaario, Annukka Santasalo-Aarnio, Rolf Reitz, Martti Larmi
Summary: The introduction of downsized, turbocharged Gasoline Direct Injection (GDI) engines in the automotive market has led to an increase in research on Low-speed Pre-ignition (LSPI) and super-knock within the last decade. LSPI is characterized by early ignition of fuel-air mixture, while super-knock is an occasional development from pre-ignition to high intensity knocking through detonation. Experimental research has included detailed approaches using different setups, and fuel and lubricant surrogates have allowed for modeling of various aspects of the phenomena. This paper provides a comprehensive review of LSPI and super-knock, discusses experimental methodologies, and suggests mitigating strategies based on fuel, oil, and engine parameters.
PROGRESS IN ENERGY AND COMBUSTION SCIENCE
(2023)
Article
Thermodynamics
Qijun Tang, Kai Ren, Xinyan Xie, Tao Chen, Ping Jiang, Daqing Zhang
Summary: This study experimentally investigated the effect of ABE and gasoline blends on knocking performance in a spark-ignition engine. The results showed that ABE can be used as a blended fuel to suppress knocking tendency.
THERMAL SCIENCE AND ENGINEERING PROGRESS
(2023)
Article
Green & Sustainable Science & Technology
Cristian Sandu, Constantin Pana, Niculae Negurescu, Gheorghe Lazaroiu, Alexandru Cernat, Rares Georgescu, Cristian Nutu
Summary: This paper analyzes the influence of butanol content in gasoline blends on engine operation, focusing on operation stability, thermal efficiency and emissions. The study finds that butanol can improve engine operation stability and energy performance, while reducing pollutant emissions.
Article
Energy & Fuels
Lker Ors, Savas Yelbey, Halil Erdi Gulcan, Bahar Sayin Kul, Murat Ciniviz
Summary: This study analyzes the combustion behavior of an SI engine and evaluates its thermodynamic performance through energy and exergy analysis. The addition of small amounts of ethanol and methanol to gasoline is compared with gasoline as the reference fuel. The study demonstrates that the addition of ethanol and methanol increases the maximum in-cylinder pressure, while reducing the average in-cylinder gas temperature and increasing the pressure increase rates. The volumetric addition of ethanol/methanol to gasoline has a decreasing effect on thermal and exergetic efficiency values.
Article
Engineering, Electrical & Electronic
Haiwen Ge, Ahmad Hadi Bakir, Peng Zhao
Summary: Hydrogen and ammonia are carbon-free fuels with massive production potential. Adding ammonia to hydrogen can effectively modulate flame speed and mitigate engine knock, while retaining the zero-carbon nature of the system. The parametric study shows the great potential of hydrogen/ammonia blends in high-speed spark-ignition engines.
Article
Thermodynamics
Seokwon Cho, Chiheon Song, Youngbok Lee, Namho Kim, Sechul Oh, Kyoungdoug Min
Summary: In order to comply with stringent CO2 regulations, internal combustion engine development has prioritized enhanced thermal efficiency, leading to engines with operating conditions more prone to knock. The limitations of current knock sensors in decomposing knock signals have necessitated the use of cross-referencing signals. This study presents a novel prediction model for knock propensity, aiming to enable active control of knock and support conventional knock sensors with a virtual knock sensor. The model incorporates predictive sub-models for in-cylinder pressure, residual gas fraction, heat loss, burn duration, and heat release rate, achieving remarkable agreement with experimental results.
INTERNATIONAL JOURNAL OF ENGINE RESEARCH
(2023)
Article
Chemistry, Physical
MohammadReza Yosri, Rahul Palulli, Mohsen Talei, Joel Mortimer, Farzad Poursadegh, Yi Yang, Michael Brear
Summary: This paper presents URANS simulations of a large bore, hydrogen-fuelled DISI engine under different spark and start of injection timings. The simulations validate four out of six cases with experimental data and demonstrate that advanced spark timing leads to autoignition. Different start of injection timings show flame propagation involving a spark-initiated flame and an autoignition generated flame. The case with late injection timing features poor mixing and slower combustion.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Energy & Fuels
Haoye Liu, Rafiu Olalere, Chongming Wang, Xiao Ma, Hongming Xu
Summary: 2-Methylfuran (MF) is considered a promising second-generation biofuel for spark ignition engines due to its better anti-knock ability and close lower heating value to conventional fuels. The study investigates the effects of engine control parameters on MF combustion at typical DISI engine operating conditions, showing that MF has a wider achievable spark timing range and more robustness to lean burn compared to gasoline and ethanol at high load. The combustion characteristics and heat release of MF are less sensitive to injection timings variations, but longer injection durations are required compared to gasoline to achieve the same engine load.
Article
Energy & Fuels
Liang Yu, Haoqing Wu, Wenbin Zhao, Yong Qian, Lei Zhu, Xingcai Lu
Summary: This study investigated the performance of n-butanol as a fuel for spark ignition aviation piston engines and compared it with gasoline. N-butanol had advantages of shorter flame development, rapid combustion, higher thermal efficiency, and lower CO and NOx emissions compared to gasoline, but led to an increase in fuel consumption. The use of n-butanol/kerosene mixed fuel with higher energy density was proposed to improve efficiency, but its antiknock performance needed enhancement through high octane additives.
Article
Thermodynamics
Isam E. Yousif, Adel Mahmoud Saleh
Summary: This study explores the feasibility of finding an alternative fuel to replace Iraqi gasoline, which contains high levels of lead and sulfur compounds that pose dangers to human health and the environment. The study examines the effects of blending butanol with gasoline on engine performance and exhaust emissions, with promising results indicating improved performance and reduced emissions compared to gasoline alone. The findings suggest that the studied blends could serve as suitable alternatives to gasoline while being environmentally friendly.
CASE STUDIES IN THERMAL ENGINEERING
(2023)
Article
Energy & Fuels
Fengnian Liu, Lei Zhou, Jianxiong Hua, Changwen Liu, Haiqiao Wei
Summary: Pre-chamber jet ignition (PJI) has positive effects on combustion efficiency and stability of kerosene, but may increase knock intensity and require ignition timing adjustment. However, PJI performs better than direct injection dual spark plugs ignition (DSPI) under critical knock conditions.
Article
Energy & Fuels
Xiaoyu Cong, Changwei Ji, Shuofeng Wang
Summary: The study found that blending DME can extend flame development and propagation periods, increase power output of the neat hydrogen engine, and reduce nitrogen oxides emissions. However, blending DME may increase cyclic variation due to weakened flame kernel and propagation process, but emissions can be controlled by adjusting the DME fraction.
Article
Energy & Fuels
Krishna C. Kalvakala, Pinaki Pal, Goutham Kukkadapu, Matthew McNenly, Suresh Aggarwal
Summary: Soot formation is a complex process that is closely related to the composition, physical and chemical properties, and combustion environment of the fuel. This study investigates the relationship between soot propensity and the octane sensitivity of the fuel. Numerical simulations reveal that the toluene content in the fuel mixture has a significant effect on polycyclic aromatic hydrocarbons (PAHs) and soot emissions, while the alcohol content and octane sensitivity show a weak correlation. A new variable based on the elemental composition of the fuel mixture, along with octane sensitivity, can satisfactorily characterize soot emissions.
Article
Thermodynamics
Shang Liu, Zhelong Lin, Hao Zhang, Nuo Lei, Yunliang Qi, Zhi Wang
Summary: Increasing the compression ratio of gasoline engines can improve fuel efficiency, but engine knock caused by auto-ignition is still a challenge for high compression ratio hybrid engines. This study investigates the effects of blending ammonia on knock suppression, combustion characteristics, thermal efficiency, and emission performance in a high compression ratio gasoline engine.
Article
Thermodynamics
Sirio Brunialti, Xiaoyuan Zhang, Tiziano Faravelli, Alessio Frassoldati, S. Mani Sarathy
Summary: This work presents a methodology for automatically generating predictive lumped sub-mechanisms for normal and branched alkanes. Detailed sub-mechanisms for alkanes are generated using an updated version of the MAMOX ++ software, incorporating recent progress in low-temperature reaction classes and rate rules. The methodology proposes a new approach to generate lumped sub-mechanisms for fuel molecules by fitting stoichiometric parameters and reaction rates to match those in the detailed model. Validations show that the detailed models capture experimental targets well, while the lumped models perform similarly for normal alkanes but have slightly greater deviations for branched alkanes.
PROCEEDINGS OF THE COMBUSTION INSTITUTE
(2023)
Article
Thermodynamics
Haitao Lu, Fuqiang Liu, Shashank S. Nagaraja, Shijun Dong, Mattias A. Turner, Olivier Mathieu, Eric L. Petersen, Jesus Caravaca Vilchez, Karl Alexander Heufer, Gang Xu, S. Mani Sarathy, Henry J. Curran
Summary: In order to reduce particulate emissions and improve air quality, it is crucial to understand the formation of polycyclic-aromatic hydrocarbons (PAHs) and their precursors during combustion, particularly for 2-butyne. This study conducted pyrolysis, oxidation, and laminar flame speed experiments for 2-butyne, and developed a comprehensive chemical kinetic model that was validated against experimental data. The research findings identify the key reactions involved in 2-butyne decomposition, ignition, and oxidation, shedding light on the formation mechanisms of PAHs and offering insights for reducing soot emissions.
PROCEEDINGS OF THE COMBUSTION INSTITUTE
(2023)
Article
Thermodynamics
Tairan Wang, Kiran K. Yalamanchi, Xin Bai, Shuyuan Liu, Yang Li, Bei Qu, Goutham Kukkadapu, S. Mani Sarathy
Summary: This study investigates the thermochemistry of OPAH species and relevant radicals using quantum-chemical calculations. Thermochemical properties for C 5 -C 18 OPAHs were determined at different temperatures, and a accurate thermochemistry database for OPAHs was developed. The existing group additivity method does not apply to OPAHs, and new group additivity values were obtained for larger OPAHs. These thermodynamic properties and group additivity values are crucial for accurate kinetic models for OPAH formation chemistry and emission control.
COMBUSTION AND FLAME
(2023)
Article
Thermodynamics
Khaiyom Hakimov, Yang Li, S. Mani Sarathy, Jihad Badra, Emre Cenker, Aamir Farooq
Summary: Ignition delay times (IDTs) of iso-octane/air mixture were measured at different conditions. The study found that IDTs were longer at lower equivalence ratio and shorter at higher pressures. Existing chemical kinetic models showed notable differences compared to the experimental data at fuel-lean conditions, and modifications were made based on sensitivity analyses to improve model performance.
COMBUSTION AND FLAME
(2023)
Article
Energy & Fuels
Felipe Campuzano, Javier Ordonez, Juan Daniel Martinez, Andres F. Agudelo, S. Mani Sarathy, William L. Roberts
Summary: This study characterizes the thermal decomposition behavior of oil derived from the pyrolysis of End-of-Life Tires (ELT) using thermogravimetric and calorimetric analyses, coupled with Fourier transform infrared spectroscopy. The results show that the oxidation and pyrolysis of the oil can be divided into three stages: low-temperature oxidation, fuel decomposition, and high-temperature oxidation. This study provides valuable insights for the use of pyrolysis oil in combustion systems.
Article
Engineering, Chemical
Nawaf M. Alghamdi, Dionisios G. Vlachos, S. Mani Sarathy
Summary: This study presents a thermodynamically consistent, density functional theory (DFT)-based parametrized microkinetic model that predicts CO oxidation on Rh at stoichiometric and lean conditions. The model accurately simulates experimental data and literature data collected under different conditions. This microkinetic mechanism can contribute to optimizing three-way catalysts to reduce CO emissions and propose cheaper alternative catalysts.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2023)
Article
Engineering, Chemical
Yuhang Yu, Sean-Thomas B. Lundin, Keisuke Obata, S. Mani Sarathy, Kazuhiro Takanabe
Summary: A comprehensive microkinetic mechanism for the oxidative coupling of methane (OCM) was developed and verified using a La2O3-CeO2 catalyst. The mechanism accurately predicted the temperature and pressure dependencies of the reaction, providing guidance for achieving high C2-3 yields.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2023)
Article
Automation & Control Systems
Khalid Alhazmi, S. Mani Sarathy
Summary: Model-based control is a prevalent technique for engineering systems, but complex systems with changing dynamics require online system identification. This study proposes an algorithm for nonintrusive, online, nonlinear parameter estimation using deep reinforcement learning. The RL-based parameter estimation policy accurately predicts system states with less than 1% error in various conditions. The algorithm is tested on a simulation of selective hydrogenation of acetylene, a highly nonlinear system. (c) 2023 Elsevier Ltd. All rights reserved.
JOURNAL OF PROCESS CONTROL
(2023)
Article
Thermodynamics
Khalid Alhazmi, S. Mani Sarathy
Summary: Combustion instability is a significant risk in the development of new engines using zero-carbon fuels. In this study, a model-free reinforcement learning algorithm is proposed to adjust the parameters of a phase-shift controller in a time-varying combustion system. The algorithm showed excellent performance in simulations, outperforming other methods. This approach has the potential to mitigate combustion instabilities and facilitate the development of safer and more efficient carbon-free gas turbine technologies.
COMBUSTION AND FLAME
(2023)
Article
Thermodynamics
Can Shao, Yitong Zhai, A. Cardenas-Salvarez, Wen Zhang, E. Grajales-Gonzalez, Xin Bai, Yang Li, M. Monge-Palacios, S. Mani Sarathy
Summary: Pyrene was pyrolyzed in a jet-stirred reactor to investigate dimerization in the soot inception temperature range (70K-120K). The chemical composition of the nucleated particles was analyzed using high-resolution Fourier transform ion cyclotron resonance mass spectrometry with laser desorption ionization. A kinetic model was built to explain the competition between physical dimerization of pyrene molecules, physical dimerization of a pyrenyl radical and a pyrene molecule, and chemical dimerization of pyrenyl radicals. The model successfully captured the observed trends and highlighted the importance of chemically-linked dimers in the inception process.
COMBUSTION AND FLAME
(2023)
Article
Thermodynamics
Shashank Sakleshpur Nagaraja, S. Mani Sarathy
Summary: Energy production from natural gas has increased globally. Understanding the reactivity of different gas blends is important for the development of fuel-source independent combustors and future engines. An artificial neural network-based model is developed to predict the ignition delay time of natural gas blends, which outperforms multiple linear regression and accurately predicts experimental data.
COMBUSTION SCIENCE AND TECHNOLOGY
(2023)
Article
Electrochemistry
Nicholas R. Cross, Holkan Vazquez-Sanchez, Matthew J. Rau, Serguei N. Lvov, Michael A. Hickner, Christopher A. Gorski, Shashank S. Nagaraja, S. Mani Sarathy, Bruce E. Logan, Derek M. Hall
Summary: In this study, the performance of thermally regenerative batteries (TRBs) was examined with the use of different membranes. It was found that an inexpensive hydrocarbon CEM (Selemion CMVN) had low ammonia crossover and good performance. Additionally, a thin anion exchange membrane (Sustainion) showed high peak power density due to low resistance, but low average power density and energy density due to high ammonia flux. Techno-economic analysis showed that Selemion CMVN had the lowest levelized cost of storage.
ELECTROCHIMICA ACTA
(2023)
Article
Thermodynamics
Khalid Aljohani, Abd El-Sabor Mohamed, Haitao Lu, Henry J. Curran, S. Mani Sarathy, Aamir Farooq
Summary: This study investigates the impact of exhaust gas recirculation (EGR) and NOx on the ignition delay time of oxygenated gasoline. A gasoline surrogate model is developed and the experimental data are useful for predicting fuel ignition behavior in internal combustion engines. The results show that EGR inhibits gasoline reactivity, while NOx has a promoting effect at high temperatures. This research is important for understanding the combustion behavior of gasoline in engines.
COMBUSTION AND FLAME
(2024)
Article
Chemistry, Physical
Scott Wiseman, Christian A. Michelbach, Hu Li, Alison S. Tomlin
Summary: This study focuses on the acid-catalysed alcoholysis of lignocellulosic biomass to produce a customizable biofuel blend. The effects of carbon chain length on the physical properties of the blends were investigated, and predictive models for these properties were developed. The study also examined the impact of blending with diesel on the properties. The findings provide valuable insights for producing biofuel blends that meet existing fuel standards.
SUSTAINABLE ENERGY & FUELS
(2023)
Article
Energy & Fuels
Basem A. Eraqi, Shashank S. Nagaraja, Et-touhami Es-sebbar, S. Mani Sarathy
Summary: This study examines the impact of NO-addition and N-2-dilution on the autoignition process of n-C-10-n-C-14 alkanes, which are crucial components of diesel and kerosene-based jet fuels. The results show that N-2-dilution consistently increases the ignition delay time (IDT) for the tested fuels, while the effect of NO-addition is temperature-dependent. The study provides valuable fundamental combustion data for n-C-10-n-C-14 fuels and fills a gap in the literature. These findings can be utilized by engine researchers to develop more efficient and cleaner combustion engine technologies.