Mechanical Engineering Commons^™

Interaction Of Particles With Plasma And Shock Produced By Pulsed Spark Discharge, Shomik Mukhopadhyay

Dissertations

Interactions of powders with high-temperature plasma and shockwaves occur in diverse scenarios, such as nuclear blasts, accidental industrial dust explosions, solid propellant combustion in explosive charges and when removing contaminants from surfaces. Electrostatic Discharge (ESD), known for generating shock and plasma, is a promising lab-scale technique for simulating these interactions. Studies with ESD involved placing powders near a spark-producing gap between electrodes and observing mechanical and chemical processes like particle motion and ignition. A limited range of spark conditions and material properties have been tested, which facilitated the development and validation of preliminary computational models describing this system. Significant gaps …

Estimation Of Useful-Stage Energy Returns On Investment For Fossil Fuels And Implications For Renewable Energy Systems, Emmanuel Aramendia, Paul E. Brockway, Peter G. Taylor, Jonathan B. Norman, Matthew K. Heun, Zeke Marshal;

University Faculty Publications and Creative Works

The net energy implications of the energy transition have so far been analysed at best at the final energy stage. Here we argue that expanding the analysis to the useful stage is crucial. We estimate fossil fuelsʼ useful-stage energy returns on investment (EROIs) over the period 1971–2020, globally and nationally, and disaggregate EROIs by end use. We find that fossil fuelsʼ useful-stage EROIs (~3.5:1) are considerably lower than at the final stage (~8.5:1), due to low final-to-useful efficiencies. Further, we estimate the final-stage EROI for which electricity-yielding renewable energy would deliver the same net useful energy as fossil fuels (EROI …

An Integrated Resource Planning Proposal For Tucson Electric Power, Valeria Bernal

Master's Projects and Capstones

An integrated resource plan (IRP) is crucial for utilities to determine the most cost-efficient energy resources while considering system reliability, environmental impact, and regulatory requirements. VitalsparK developed an IRP for Tucson Electric Power (TEP) to transition its current 70% thermal and 30% renewable energy portfolio, emitting 740 grams of CO2 per kWh, toward carbon neutrality by 2050. The proposed plan involves retiring existing infrastructure, adding 8 GW of renewable and storage capacity, and incorporating 2.5 GW of net-zero natural gas power plants. VitalsparK presented two scenarios: the Reference (REF) Case, which focuses on the least-cost portfolio to meet demand through …

Regular Algorythms For Synthesis Of Optimal Control Systems For Dynamic Objects, Igamberdiyev Husan, Uktam Farkhodovich Mamirov, Xankeldiyeva Zebiniso

Technical science and innovation

The article presents algorithms for the synthesis of an optimal control system for dynamic objects. As a model, we consider a differential equation of a continuous one-dimensional system in the form of a state space, which has the properties of controllability and observability. The paper shows the need to use an observation device in order to assess how the properties of the controlled system change with the slightest change in the parameters of the control object, to assess the sensitivity of the system to these changes. When finding a solution to the equation formulated to find the parameters of the …

Studying The Production Of Nanocelluloses, Shohzodbek Abduvahobovich Rashidov, Elmurod Abduqodirovich Egamberdiev, Sadritdin Maxamatdinovich Turabdjanov

Technical science and innovation

Nanoscience is a broad field that includes nanophysics and nanochemistry. Nanotechnologies are aimed at obtaining nanoparticles with new properties and creating materials and devices based on them. This is one of the modern trends in the development of science in the 21st century.

Based on the study of information about nano-sized materials, the mechanisms of their production and changes in their properties, we will consider the technology for producing nanocellulose from organic substances, i.e. from cellulose. The article describes a technology that examines devices for producing nanocellulose and the principles of their operation, as well as a combined method of …

Modeling Of Continuous Stirred Tank Reactor For Esterification Process, Olimjon Rikhsiboyevich Maksudov, Abdulaziz Nodirbek Ogli Bakhtiyorov, Orifjon Olimovich Zaripov, Аdhаm Tilovovich Norkobilov

Technical science and innovation

This paper presents a comprehensive study on the synthesis of ethyl acetate through the esterification of acetic acid with ethanol using a continuous stirred tank reactor (CSTR). Ethyl acetate is a significant solvent in various industries due to its eco-friendly characteristics and economic efficiency. The study develops a detailed mathematical model focusing on the operating of the CSTR to enhance the understanding of the reaction kinetics and thermodynamics in a continuous processing environment. The reactor model was validated with experimental data to optimize process parameters, aiming to improve yield and selectivity. Key variables such as reactant ratios, and operational temperatures …

Comparative Analysis Of Cutting Forces In Axial-Compliant And Rigid Chamfering Tools, Sultonmurod Bekpulatovich Normatov, Oybek Tuyboyov, Azimjon Axror O'G'Li Pardayev, Alisher G‘Ayratjon Ogli Boratov, Shohjahon Tuxtasin Ogli Abdullayev

Technical science and innovation

This study delves into the analysis of cutting forces in axial-compliant systems, focusing specifically on the comparison between axially spring-compensated 90° conical tools and rigid chamfering tools. The research incorporates a predictive model for chamfer size calculation in the axially spring-compensated tools, verified through experimental tests on representative parts. The study aims to control chamfer size within tolerances by adjusting process conditions and optimizing processing efficiency. By exploring the fundamentals of the chamfering process, this research offers insights into breaking sharp edges on components with positional errors and shape deformations, with a particular emphasis on aero-engine casings. The integration of …

Bottling Automation System, Dylanie Tippit

Honors College Theses

This report details the complete design of an automated bottling system. Each bottle is 5.97 centimeters tall and has an outer diameter of 3.81 centimeters. The goal of the project is to successfully fill and cap twelve bottles in under three and a half minutes. The system will have two conveyors in series, a water dispenser, an electrolyte dispenser, capping station, Human Machine Interface (HMI) and Allen Bradley programmable logic controller (PLC). The water and electrolyte dispenser will have two ball valves in series, with the desired amount of volume to dispense the designated liquid. The capping station will be …

Development Of A Multi-Use Modular Microfluidic Platform Using 3d Printing, Carson Emeigh

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Microfluidic lab-on-a-chip (LoC) technology has driven numerous innovations due to their ability to perform laboratory-scale experiments on a single chip using microchannels. Although LoC technology has been innovative, it still suffers from limitations related to its fabrication and design flexibility. Typical LoC fabrication, with photolithography, is time consuming, expensive, and inflexible. To overcome the limitations of LoC devices, modular microfluidic platforms have been developed where multiple microfluidic modules, each with a specific function or group of functions, can be combined on a single platform. Modular microfluidics have overcome some of the limitations of LoC devices, but currently, their fabrication is …

Summonable Construction Delivery Robot, Kevin M. Lewis

Honors Capstones

In many different construction industries, there is a need for tools, parts, and other necessary items to be transported quickly and efficiently over various types of terrain. Human resources have often been used to address these needs, which can become very time and cost inefficient over long periods. The design proposal here is aimed at addressing this need by developing an autonomous outdoor mobile robot based on a quadrupedal robot design. This approach differs by incorporating a wheeled and quadrupedal hybrid actuation system that provides terrain negotiation and speed at the appropriate times. The team uses Robot Operating System (ROS) …

Keratin-Based Film: Waste To Bioplastic, Emma Bond

University Honors College

The solution to plastic lies in alternative materials, like bioplastics. One such possibility is keratin-based films. They are made from sources that are already deemed to be waste and that all regions of the world are abundant in. Manufacturing values a one-size-fits-all solution and keratin being plentiful worldwide fulfills that set standard. The films’ properties, which are important to the basic needs of a package, vary with different additives and the type of keratin used. α-keratin and β-keratin have different strengths and are found in nature in different sources. The resource focused on was chicken feathers, which produce more β-keratin …

Developing General Purpose Apps To Automate Image Analysis Of Wave-Augmented-Varicose-Explosion Atomization And Other Multi-Phase Interfacial Flows, Ethan Newkirk

Senior Honors Theses

Atomization involves disrupting a flow of contiguous liquid into small droplets ranging from one submicron to several hundred microns (micrometers) in diameter through the processes of exerting sufficient forces that disrupt the retaining surface tensions of the liquid. Understanding this phenomenon requires high-speed imaging from physical models or rigorous multiphase computational fluid dynamics models. We produce a MATLAB application that utilizes various methods of image analysis to quickly analyze and store mathematical data from detailed image analyses. We present a user with numerous tools and capabilities that provide results that deviate from 1.8% to 8.9% of the original image sequence …

Characterizing The Molecular And Cellular Changes Of Senescent Cells Induced By Diverse Stressors In 2d And 3d Microenvironments, Apoorva Chauhan

UNLV Theses, Dissertations, Professional Papers, and Capstones

Aging is a risk factor for myriad diseases and is often associated with the accumulation of senescent cells. Cellular senescence, a process of irreversible cell cycle arrest, is associated with various changes in cellular morphology and function. While senescence will occur naturally in a time-dependent manner, it can be prematurely induced by various extrinsic and intrinsic factors. Most senescence studies model cell behavior in two-dimensional (2D) microenvironments; however, these models are not physiologically relevant. In this study, the effects of naturally occurring reactive oxygen species (ROS) hydrogen peroxide (H2O2) and commonly used chemotherapy drugs, doxorubicin and palbociclib, on cellular senescence …

Optimization Pump As Turbine Coupled To A Self-Excited Induction Generator Using Multi-Objective Genetic Algorithm, Emanuel J. Nyirenda

Tanzania Journal of Engineering and Technology (TJET)

As a way of accelerating the deployment of affordable and clean renewable energy generation technologies, applying a pump working as a turbine coupled to a self-excited induction generator is gaining popularity in various areas including energy recovery and micro hydro systems. However, it is currently challenging to predict the performance of the PAT-SEIG system and there is no agreed-upon rule on the selection of the appropriate system to be installed at a particular site. This paper has presented multi-objective optimization to select the best operating point of the PAT-SEIG system. The results show that the peak efficiencies for the PAT …

Optimal Load Shedding During Service Restoration In Electrical Secondary Distribution Network Based On Reinforcement Learning, Rukia J. Mwifunyi

Tanzania Journal of Engineering and Technology (TJET)

Increased stress in traditional power systems results in blackouts due to voltage instability attributed to a mismatch between available capacity and load demand, especially in distribution networks. Service restoration schemes are designed to return power supply to the affected parts of the networks. The availability of insufficient supply is a complex problem that requires operational experience or an automatic system. The stochastic nature of load demand significantly impacts service restoration as it results in increased restored demand in case a fault occurs during off-peak hours and helps reduce overload if the fault occurs during peak hours. The study adopts an …

Assessment Of Risk Factors Related To Body Pain Complaints In Tanzania Construction Industry, Fatma K. Mohamed

Tanzania Journal of Engineering and Technology (TJET)

The construction industry is associated with risks that can result in musculoskeletal diseases. Although young male workers who are presumed to be healthy dominate the industry in Tanzania, body pain complaints have been widely reported. The aim of this study is to assess the prevalence and causes of body pains in workers. A cross-sectional study involving 396 workers was conducted. A chi square test was used for testing association of independent categorical variables and binary logistic regression analysis was used to determine predictors for body pain complaints. The results show that all study participants complained of at least one form …

Comparison Of Meteorological Drought Indices In Tanzania Using The Meteorological Drought Monitoring Software Package, Paul Ts Limbu

Tanzania Journal of Engineering and Technology (TJET)

Low precipitation, substantial evaporation, and an unequal distribution of precipitation throughout the area are the characteristics of drought, a climatic abnormality. This study used the Meteorological Drought Monitoring (MDM) software and monthly rainfall data from the Tanzania Meteorological Authority (TMA) to examine and compare the Deciles Index (DI), Standardised Precipitation Index (SPI), Percent of Normal Index (PNI), Rainfall Anomaly Index (RAI), Z-Score Index (ZSI), China-Z Index (CZI), and Modified China-Z Index (MCZI) for drought monitoring in Tanzania from 1988 to 2017. It was found that ZSI represented the dry years better than other indices, followed by DI, RAI, PNI, SPI, …

An Optimization Tool For A Standalone Photovoltaic System, Johanes Kasilima

Tanzania Journal of Engineering and Technology (TJET)

Stand-alone photovoltaic systems (SAPV) are often used in remote areas where access to grid electricity is limited. This system depends on solar energy. However, Photovoltaic (PV) systems need a greater initial investment than conventional sources of energy, and their effectiveness is reliant on a number of environmental conditions such as the unpredictable solar radiation. One step in reducing the investment cost of a PV system is determining the optimal size of solar PV components that minimize costs. This paper presents a Particle Swarm based optimization tool for sizing Stand-alone PV systems. The optimization tool selects the optimal Levelized Cost of …

Reducing Glass Loss During Transportation And Storage, Abdulaziz Muzafarovich Qurbanov, Mirzaabdullayev Jaxongir Baxtiyorovich

Technical science and innovation

The article discusses the processes of transportation and storage of sheet glass in the production of protective glass for cars. The experience of organizing the transportation and storage of glass in developed countries of the world was analyzed in order to study the problems of losses of raw materials during the transportation and storage of laminated glass, as well as to develop and approve a regulatory and technical document. in this field. The supplies of various brands of polished laminated glass used in the production of protective glass for cars to Avtooina LLC from different addresses, from different manufacturers were …

Ferroresonance In Three-Phase Electrical Networks, Shavkat Ernstovich Begmatov

Technical science and innovation

Possible modes of ferroresonance in three-phase electric networks and analysis of substitution schemes where ferroresonance voltage increase is observed are considered. The most complete magnetization curve of the transformer core and the analysis of the generalized equivalent substitution scheme are presented, as a result of which more accurate formulas for determining the values of equivalent parameters of the electrical network and voltage transformer in ferroresonance mode are obtained. Factor of ferroresonance voltage increase is introduced, which determines ratio between amplitude values of transformer phase voltage and mains voltage. The method of determination of boundary conditions of steady ferroresonance voltage increase …

Main Prospects Of Natural Gas Purification Technologies From Acidic Compounds, Oybek Yusupdjanovich Aripdjanov, Diyora Zokhid Qizi Khayrullaeva, Jonibek Avazek Ogli Abdumuminov

Technical science and innovation

The article discusses the main prospects for the technology of purifying natural gas from acidic components and the problems of ensuring the purity of oil and gas products in accordance with state standards. An increase in the degree of purification from H₂S, CO₂, elemental sulfur, carbonyl sulfide, ethyl mercaptans (thiols), methyl mercaptan, carbon disulfide, sulfides, disulfides (dithioethers), thiophene, sulfoxides and sulfones is considered. Also, the physicochemical properties of the absorbent for the purification of sulfur compounds (generated during natural gas processing) are studied. Based on the study of various absorbents (ethanolamine (EA), methylethanolamine (MEA), diethanolamine (DEA), …

Use Of Mathematical Skills For Technical Condition Assessment Of Power Autotransformers, Dilafruz Rustamjon Qizi Abdullabekova, Nurali Berdiyorovich Pirmatov

Technical science and innovation

In this paper, we review innovative approaches to assess the technical condition of autotransformers using mathematical methods. The main purpose of these methods is to increase the efficiency of diagnostics and prevent possible failures in power systems. The developed mathematical expression is based on complex data analysis, application of statistical methods and machine learning technologies. This makes it possible to achieve more accurate and earlier detection of potential problems. As a result of these innovative approaches, the possibilities for early detection and prevention of faults are significantly increased. This is important for ensuring the smooth operation of power systems and …

Quantitative Assessment And Characterization Of Tool Wear Phenomena In Advanced Manufacturing Processes, Oybek Valijonovich Tuyboyov

Technical science and innovation

This paper explores the quantitative assessment and characterization of tool wear phenomena in advanced manufacturing processes, employing a multifaceted approach encompassing traditional measurements, image processing, machine learning, and predictive modeling. The study emphasizes the intricate dynamics of tool wear and its direct impact on cutting tool performance, addressing challenges in real-time monitoring and optimization of machining operations. Traditional methods like VBmax measurement are juxtaposed with advanced techniques such as the improved conditional generative adversarial net with a high-quality optimization algorithm (CGAN-HQOA), efficient channel attention destruction and construction learning (ECADCL), and shape descriptors based on contour, moments, orientations, and texture. Artificial …

Implementing A Solar Photovoltaic Station In Watering Systems Utilizing Complex Software, Akbarxon Sarvar O'G'Li Uroqov, Faxriddin Jaylovovich Nosirov, G'Olibjon Pardayevich Arzikulov, Zarina Amriddin Qizi Sayfutdinova

Technical science and innovation

This article explores the benefits of transitioning from traditional agricultural irrigation systems to more cost-effective alternatives powered by renewable energy sources. By integrating solar photovoltaic technology into irrigation processes, significant reductions in resource wastage, estimated at 45-50%, are achievable through the implementation of drip irrigation techniques. This results in enhanced agricultural productivity. Moreover, the utilization of solar panels in green zones mitigates surface temperature increases, contributing to a 2-5% boost in electricity production. Currently, irrigation facilities primarily rely on the main energy grid. However, transitioning to renewable energy sources decreases reliance on non-renewable fuels, reduces greenhouse gas emissions, and fosters …

Selective Oxidation Of Iron In Chalcopyrite For Enhanced Copper Recovery, Khojiakbar Shuxrat O'G'Li Sultonov, Shokhrukh Toshpulatovich Khojiev, Gulnoza Berdiyor Qizi Beknazarova, Malika Sayfullayevna Saidova

Technical science and innovation

This study explores the thermodynamic feasibility of selectively oxidizing iron contained in chalcopyrite mineral while preventing the oxidation of copper sulphide, with the ultimate goal of enhancing the copper concentration in the sulphide concentrate. A redox reaction in the solid phases between chalcopyrite and copper (I) oxide was constructed and subjected to thermodynamic analysis. The research identifies a crucial temperature range of 498-598 K (225-325 °C) as the most favourable for the redox reaction. The equilibrium constants at the selected optimal temperatures, 1.152 for chalcopyrite and 1.137 for copper (I) oxide, indicate that the redox reaction adheres to the expected …

Solving Water Resources Problems - Water Saving In The Republic Of Uzbekistan, Rustam Muxammatdjanovich Raximov

Technical science and innovation

In this article we will talk about the problems of water resources in the Republic of Uzbekistan. The problem of drinking water supply, solutions to provide drinking water to the population of Uzbekistan. The largest consumers of fresh water in Uzbekistan are farmers. Due to outdated infrastructure, 40% of water is wasted. Rising food prices and the risk of spreading disease are the first signs of water shortages that we may experience in the coming еars. Uzbekcosmos told how to solve the problem. Water is an invaluable resource used not only in the home, but also in the production and …

Modelling Of Heat Transfer In An Air Solar Collector, Shakhnoza Abduvaxitovna Sultanova, Jasur Esirgapovich Safarov, A.A. Mambetsheripova

Technical science and innovation

This study is the prediction, depending on time and different geographical and climatic situations, of different operating parameters: solar radiation, ambient and outlet coolant temperature, heat exchange coefficients and losses. All these determine, in the absence of measurements, the efficiency of the system modelled with existing models with respect to these parameters. These models are usually compared with experimental results. Before modelling, it is necessary to investigate the different heat transfer and exchange regimes that exist between the different elements of this system in order to eventually have a system of equations governing this exchange. The modelling principle is to …

A Study On The Influence Of Cutting Parameters On Surface Roughness And Visualization Through Contour Plots And 3d Surface Profiles, Zayniddin Nosirovich Muxiddinov

Technical science and innovation

This research investigates the intricate relationship between cutting parameterscutting speed, feed rate, and depth of cut and surface roughness in machining processes. Surface roughness is a key determinant of machined surface quality, and optimizing cutting parameters is crucial for achieving superior finishes. Employing advanced visualization techniques, including contour plots and 3D surface profiles, the study offers a comprehensive exploration of surface topography dynamics. Statistical analyses and regression modeling enhance the quantitative understanding of how cutting parameters interact to shape surface roughness. The research affirms the significant influence of cutting speed, feed rate, and depth of cut, providing practical insights for …

Theory Of Development And Improvement Of The Mathematical Model Of The Methodology Of Public Control In The Management Of Occupational Safety And Industrial Risks, Aliakbar Khamidullaevich Rasulev, Sunnatilla Suleymanovich Suleymanov, Nodira Bakhadirzhanovna Gaibnazarova

Technical science and innovation

The article develops and analyzes a mathematical model based on a logical flowchart of the methodology of public control in the management of occupational safety and industrial risks and probability theory, according to the model, the results of compliance with the requirements of social cooperation on occupational safety lead to a sharp increase in the probability of reliability, management efficiency becomes higher. Analysis of the mathematical model of the developed logical flowchart based on probability theory has shown that when the parties cooperate to monitor the results of compliance with labor protection requirements, they lead to a sharp increase in …

Research Of The Influence Of Dust On Photovoltaic Modules, Anvarjon Mirolimov, Xalmurat Iliev

Technical science and innovation

The influence of dust concentrations on the current-voltage characteristics (voltampere characteristics) of photovoltaic modules (PVM) based on crystalline silicon in laboratory conditions. It was investigated how an uncleaned panel affects the output power. The tests were carried out in the city of Tashkent on the territory of the “National Research Institute of Renewable Energy Sources”. The objects were located co-plurally as specified in GOST R 60904-1 Photoelectric devices. Part 1. Measurement of current-voltage characteristics. Measurements of a cleaned photovoltaic module with a maximum power of 330 W and not a cleaned one of 236 W were obtained. Based on the …