Engineering Commons^™

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.

Strategic Value And Scientific Exploration Of In-Situ Pyrolysis Of Tar-Rich Coals, Wang Shuangming, Shi Qingmin, Sun Qiang, Cui Shidong, Kou Bingyang, Qiao Junwei, Geng Jishi, Zhang Lei, Tian Hua, Jiang Pengfei, Cai Yue, Liu Lang

Coal Geology & Exploration

Background Given China's significant demand shortfall of oil and gas, numerous constraints on oil and gas supply, an arduous task of green and low-carbon energy transition of coals, tar-rich coals, a type of coal resource integrating the properties of coal, oil, and gas, have great potential for increasing the oil and gas supply of the country. Advances Despite the successful engineering test conducted in Yulin, Shaanxi Province, in-situ pyrolysis of tar-rich coals remains in its exploratory stage. This technology holds great strategic value in two aspects: (1) It enables reduced demand shortfall of oil and gas in China to enhance …

Numerical Simulations Of The Evolutionary Patterns Of Multi-Physical Fields During The In-Situ Pyrolysis Of Tar-Rich Coals, Yang Fu, Cheng Xiangqiang, Li Mingjie, Wu Zhiqiang, Wei Jinjia, Cao Husheng

Coal Geology & Exploration

Objective The in-situ pyrolysis of tar-rich coals, an emerging technology for coal resource utilization characterized by cleanliness, high efficiency, and safety, is still in its initial development stage. This technology is greatly influenced by the evolutionary patterns of multi-physical fields and critical process parameters. Methods A numerical simulation model involving multi-physical fields was established by coupling fluid flow, heat transfer, and chemical reactions, and its reliability was verified by comparing the numerical simulation results with the pyrolysis experimental results of cylindrical coal samples. Based on the pilot test conditions, the impacts of permeability, heat-carrier flow rate, and fracture zone height …

Impacts Of The Caking Property Of Tar-Rich Coals On Their Pore Structure Evolution And Seepage During Pyrolysis, Chang Zhibing, Wang Chuchu, Kuang Wenhao, Tang Ying, Wu Xiaodan, Liu Shuqin

Coal Geology & Exploration

Objective The in-situ pyrolysis of tar-rich coals stands as a technique whereby coal seams are heated underground to produce tar and gas products. During the in-situ pyrolysis, the injection of heating media and the production of tar and gas are affected by the pore structure and permeability of coal seams. Since pyrolysis of caking tar-rich coals is accompanied by the formation of colloids, the pore structure and permeability of caking tar-rich coals differ from those of non-caking tar-rich coals. Methods Caking tar-rich coals were pyrolyzed at 300, 400, 500, and 600 ℃. During the pyrolysis, the pore parameters of the …

Identification Of Tar-Rich Coal Based On The True Density And Natural Gamma Ray Response Of Coals, Shi Qingmin, Geng Xuhu, Wang Shuangming, Cai Yue, Han Bo, Wang Shengquan, Zhang Zhehao, He Yufei

Coal Geology & Exploration

Objective Tar yield, derived from the Gray-King assay, serves as the sole metric for evaluating tar-rich coal. However, insufficient exploration data hinder its effective application in the fine-scale evaluation of extensive tar-rich coal. Methods Based on binary classification, this study proposed the optimal thresholds for tar-rich coal identification using true density (ρ) and natural gamma-ray (GR) log. Moreover, this study elucidated the intrinsic mechanisms behind the significant petrophysical parameter responses of tar-rich coal. Results and Conclusions Key findings are as follows: (1) Coals with various metamorphic grades differ in identification threshold. For instance, long-flame tar-rich coal, the optimal …

A Log-Based Method For Evaluating The Tar Yield Of Tar-Rich Coal, Tian Han, Li Ning, Wang Shuangming, Wu Hongliang, Feng Zhou, Wang Kewen, Wang Guiwen

Coal Geology & Exploration

Objective As a kind of coal-based oil and gas resource, tar-rich coal is significant for the supply of oil and gas resources, as well as the clean and efficient utilization of coals. Presently, the identification of tar-rich coals primarily depends on the Gray-King assay. In contrast, there is a lack of studies on the accurate identification and evaluation of tar-rich coal using geophysical methods. Methods This study investigated coals in the Jurassic Xishanyao and Badaowan Formations in Santanghu Basin, Xinjiang. Based on petrophysical experiments, as well as the typical log response characteristics of tar-rich coal, this study developed a new …

A Method For Predicting The Tar Yield Of Tar-Rich Coals Based On The Bp Neural Network Using Multiple Indicators Of Coal Petrography And Coal Quality, Qiao Junwei, Wang Changjian, Zhao Hongchao, Shi Qingmin, Zhang Yu, Fan Qi, Wang Duo, Yuan Dandan

Coal Geology & Exploration

Objective Tar yield, the most important coal quality parameter for coal utilization through low-temperature pyrolysis, determines the clean utilization of tar-rich coals. However, various constraints result in limited test data on tar yield in the geological exploration stage of coals, substantially restricting the fine-scale assessment and efficient utilization of tar-rich coals. Methods To achieve more scientific and accurate fine-scale tar-rich coal assessments, this study examined 1073 sets of lithotype and coal quality data obtained previously from a Jurassic coalfield in northern Shaanxi. From these data, 141 sets with 20 lithotype and coal quality parameters regarding macerals, proximate analysis, ultimate analysis, …

Performance Of Carbon Foams Based On Heavy Tar Produced By Tar-Rich Coal Pyrolysis, Zhang Lei, Liu Chunjiang, Song Ruikang, Wang Qi, Chen Ya, Huang Pengcheng

Coal Geology & Exploration

Objective Preparing graphitized foam materials using heavy tar produced by the pyrolysis of tar-rich coals plays a significant role in the high-value utilization of tar-rich coal resources. Methods This study aims to prepare high-performance carbon foam materials by investigating the relationships between various reaction conditions and carbon foam performance. First, using mesophase asphalt prepared with heavy tar as the precursor, carbon foams were developed via the high-temperature self-foaming method. Then, the effects of different reaction temperatures, heating rates, and reaction pressures on the performance of coal tar-based carbon foams were examined. Finally, quadratic multinomial regression equations were established using Box-Behnken …

Ultrasonic Cigarettes: Chemicals And Cytotoxicity Are Similar To Heated-Coil Pod-Style Electronic Cigarettes., Esther E. Omaiye, Wentai Luo, Kevin J. Mcwhirter, Prue Talbot

Civil and Environmental Engineering Faculty Publications and Presentations

Our purpose was to test the hypothesis that ultrasonic cigarettes (u-cigarettes), which operate at relatively low temperatures, produce aerosols that are less harmful than heated-coil pod-style electronic cigarettes (e-cigarettes). The major chemicals in SURGE u-cigarette fluids and aerosols were quantified, their cytotoxicity and cellular effects were assessed, and a Margin of Exposure risk assessment was performed on chemicals in SURGE fluids. Four SURGE u-cigarette flavor variants ("Blueberry Ice," "Watermelon Ice," "Green Mint," and "Polar Mint") were evaluated. Flavor chemicals were quantified in fluids and aerosols using gas chromatography/mass spectrometry. Cytotoxicity and cell dynamics were assessed using the MTT assay, live-cell …

Examining Driver Injury Severity In Motor Vehicle Crashes: A Copula-Based Approach Considering Temporal Heterogeneity In A Developing Country Context, Shahrior Pervaz, Tanmoy Bhowmik, Naveen Eluru

Civil and Environmental Engineering Faculty Publications and Presentations

Using data from a developing country, the current study develops a copula-based joint modeling framework to study crash type and driver injury severity as two dimensions of the severity process. To be specific, a copula-based multinomial logit model (for crash type) and generalized ordered logit model (for driver severity) is estimated in the study. The data for our analysis is drawn from Bangladesh for the years of 2000 to 2015. Given the presence of multiple years of data, we develop a novel spline variable generation approach that facilitates easy testing of variation in parameters across time in crash type and …

Me-Em Enewsbrief, June 2024, Department Of Mechanical Engineering- Engineering Mechanics, Michigan Technological University

Department of Mechanical and Aerospace Engineering eNewsBrief

No abstract provided.

Molecular Modeling Of Tar-Rich Coals From Northern Shaanxi And Their Molecular Dynamic Characteristics In The Process Of Pyrolysis For Tar Extraction, Guo Wei, Yang Panxi, Yu Zunyi, Yang Fu, Wang Jing, Ma Li, Li Hongqiang, Yang Bolun, Wu Zhiqiang

Coal Geology & Exploration

Objective The pyrolysis process and mechanism of tar-rich coals remain unclear due to their complex structures. Therefore, it is necessary to investigate the structure-activity relationship between their structure and the distributions of their pyrolytic products and determine the mechanism behind their pyrolysis for tar extraction. Methods Focusing on typical tar-rich coals from northern Shaanxi Province, this study calculated and constructed the molecular model of the coals using characterization methods such as carbon-13 nuclear magnetic resonance (¹³C NMR), Fourier transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS), determining the molecular formula at C₄₄₄H₃₈₀O_{74 …}

Advances In Research On Hydrogenation Saturation Of Polycyclic Aromatic Hydrocarbons In Coal Tar, He Xinfu, Gao Fan, Wu Hongju, Zhang Xiaoqin, Ma Tao, Shi Zhiwei, Zhou Anning, Zhang Yating

Coal Geology & Exploration

Significance Polycyclic aromatic hydrocarbons (PAHs), a predominant component in coal tar, can be used to produce jet fuels with high energy density and thermal stability through hydrogenation saturation. Based on the characteristics of the PAH hydrogenation process, this study proposed that primary challenges in PAH hydrogenation saturation include the resonance energy of PAHs themselves, the spatial site resistance of hydrogenation intermediates, and the competitive adsorption of feedstocks and intermediates on active sites in the catalysts. Progress Based on the review of research progress in catalysts for PAH hydrogenation saturation in recent years, this study analyzed the substantial factor influencing the …

Vertiport Ventures: Assessing Operational Feasibility For Evtol Integration In São Paulo’S Helipad And Heliport Infrastructure, Peter E. O'Reilly, Ramy A. Rahimi, Jorge Luiz Rosa Marques, Marco Aurélio Feitosa De A. L. Babadopulos1

Publications

The objective of this study is to assess the operational viability of introducing Electric Vertical Take-Of and Landing (eVTOL) vehicles in São Paulo and its metropolitan area, utilizing existing helipads and helicopter infrastructure. eVTOL aircraft, capable of vertical take-of and landing like helicopters, difer from traditional helicopters in their propulsion systems, with eVTOLs typically featuring multiple smaller electric motor-driven propulsion units instead of internal combustion engines and mechanical transmissions (Schuchardt et al. 2023). The study specifcally targets eVTOLs with the capacity to transport a minimum of four passengers and one pilot for distances of at least 50 km. Appendix provides …

A Survey On Fused Filament Fabrication To Produce Functionally Gradient Materials, Arup Dey, Monsuru Ramoni, Nita Yodo

Manufacturing & Industrial Engineering Faculty Publications

Fused filament fabrication (FFF) is a key extrusion-based additive manufacturing (AM) process for fabricating components from polymers and their composites. Functionally gradient materials (FGMs) exhibit spatially varying properties by modulating chemical compositions, microstructures, and design attributes, offering enhanced performance over homogeneous materials and conventional composites. These materials are pivotal in aerospace, automotive, and medical applications, where the optimization of weight, cost, and functional properties is critical. Conventional FGM manufacturing techniques are hindered by complexity, high costs, and limited precision. AM, particularly FFF, presents a promising alternative for FGM production, though its application is predominantly confined to research settings. This paper …

Distributed Energy Trading Models Utilizing Reinforcement Learning And Game-Theoretic Based Approaches In Smart Grids, Nicholas Kemp

Electrical and Computer Engineering ETDs

Community-driven energy initiatives have become crucial for effective energy management, particularly in trading and management. The rise of Distributed Energy Resources in smart grids demands a redesign of traditional Demand Response Management (DRM) models to account for prosumers' dynamic behavior in energy markets. Decentralization, including peer-to-peer (P2P) energy trading, is vital for resilience and sustainability. This thesis introduces two coalitional DRM models: one based on hedonic community formation games, and the other combining matching theory with coalition games. These models empower prosumers to autonomously select energy trading communities using partially available data. To optimize energy consumption, two additional models are …

Sofast Cad Layout Tool, Felicia Brimigion

Mechanical Engineering ETDs

Concentrating solar mirrors need to have correct geometry to accurately focus sunlight onto a receiver. SOFAST is a tool created at Sandia National Laboratories which measures a mirror’s surface normal at a dense sampling of points, enabling evaluation of a given mirror’s expected performance. SOFAST supports general mirrors, including concentrating solar heliostats, troughs, and dishes. The examples presented in this report predominantly focus on heliostats.

There are generally four major components of a SOFAST system – the mirror, camera, projector, and screen. For SOFAST to properly measure a mirror, the following geometric constraints must be satisfied:

1. The reflection of …

Notes For Contributors, Space And Defense

Space and Defense

No abstract provided.

Waging Peace On The Final Frontier 64th Academy Assembly Proceedings, Space And Defense, Madison Walker

Space and Defense

In October 2022, the 64th annual Academy Assembly at the U.S. Air Force Academy took up the theme of “Waging Peace on the Final Frontier.” The following are proceedings of roundtables held by select undergraduates from around the country on questions of space policy & strategy.

Revitalizing America's Low-Yield Deterrent, Alex Kleitz

Space and Defense

An array of low-yield weapons will play a vital role in integrated deterrence. *The following essay, submitted in June 2022, earned the Junior Division USSTRATCOM General Larry D. Welch Deterrence Writing Award.

Operational Energy Solutions For A 21st Century Battlefield, Nestor R. Levin

Space and Defense

Development of alternative energy storage and distribution capacity for the modern battlefield is a major national security interest.

Annual Truman Lecture Usafa 64th Academy Assembly, John Shaw

Space and Defense

In October 2022, on the occasion of the 64th annual Academy Assembly, focused on “Waging Peace on the Final Frontier,” the deputy commander of USSPACEOM Lieutenant General John Shaw spoke at the Air Force Academy’s endowed Truman Lecture, which itself was created to inspire cadets toward careers in National Security leadership.

Usafa 64th Academy Assembly Banquet Keynote On Nasa Transformation, Madison Walker, Lori Garver

Space and Defense

In October 2022, at the 64th annual Academy Assembly, focused on “Waging Peace on the Final Frontier,” the former deputy administrator of NASA the Honorable Lori Garver spoke at the Air Force Academy’s 64th Academy Assembly banquet keynote on the implications of NASA transformation for international security. She was introduced in a pre-recorded video by Susan Eisenhower, honorary founder of USAFA’s Eisenhower Center, and interviewed by USAFA Institute for Future Conflict Fellow Madison Walker.

The Unified Command Plan For A New Cold War, David Stilwell

Space and Defense

No abstract provided.

Consulting To Avoid Kessler, Madison Walker

Space and Defense

The consultation obligation of Article IX from the Outer Space Treaty may be used to create a framework for sharing space situational awareness data, globally, with the intention of facilitating enduring coordination agreements for collision avoidance.

Protecting The Cosmos: Defining Celestial Bodies In The Outer Space Treaty, David Epstein

Space and Defense

Lack of a clear definition of the term “celestial bodies” as used in the 1967 Outer Space Treaty risks exporting legal and political conflict into the cosmos. *This essay is updated from a previously published version and appears here by permission of the Journal of Space Law at Ole Miss.

Editor's Note, Damon Coletta

Space and Defense

No abstract provided.

Table Of Contents, Space And Defense

Space and Defense

No abstract provided.

Front Matter, Space And Defense

Space and Defense

No abstract provided.

Space And Defense Volume 15 No. 1 Spring 2024 (Whole Issue), Space And Defense

Space and Defense

No abstract provided.