Other Mechanical Engineering Commons^™

Ternary Flow Simulation Based On The Conservative Phase Field Lattice Boltzmann Method, Chunheng Zhao

Dissertations and Theses

In this thesis, we numerically investigated multi-phase fluid dynamics (2 and 3-phase flow) by solving the Navier-Stokes equations coupled with the conservative phase field (CPF) equations using the Lattice Boltzmann method (LBM). To effectively simulate the large-scale multi-phase physics, we developed an open-source software, IMEXLBM, which can be easily parallelized on both CPUs and GPUs without significant modifications to the code. We first validated various parts of this software and then used this method to study the interaction of rising bubbles with a static oil droplet as well as the engulfment of the water droplet on solids coated with a …

Understanding The Relationship Between Urban Areas And The Boundary Layer Using Remote Sensing Methods, Gabriel A. Rios

Dissertations and Theses

The atmospheric boundary layer is crucial to the exchange in energy between the Earth's surface and the atmosphere. Within this layer, the majority of human activities are carried out, which makes understanding the boundary layer especially important for many of our interests. A key component of this energy exchange is found at the surface, was surface properties are the interface through which momentum, heat, moisture, and other fluxes are transferred between media. Not only does the surface act as an interface, but as an actor that influences the exchange efficiency and rates. This concept is the crux of atmospheric boundary …

Branched Chain Amino Acid Strain State Monitoring With Raman Spectroscopy And Plasmonic Bowtie Nanoantenna Devices For Early Disease Detection, Caroline A. Campbell

Theses and Dissertations

This work centers on the development and the down-selection of nano-manufactured devices to be used in conjunction with Raman spectroscopy for probing a branched chain amino acid. The nano-manufactured devices integrate plasmonic nanoantennas for the purpose of amplifying molecular fingerprints, which are otherwise difficult to detect, through Surface Enhanced Raman Spectroscopy (SERS). Plasmonic nanostructures can be utilized for a variety of biomedical and biochemical applications to detect the characteristic fingerprint provided by Raman Spectroscopy. The nano-manufactured devices create an electric field that amplifies minute perturbations and raises the signal above background noise. This may provide a deeper understanding of signal …

Development And Optimization Of A Low Volume Air-Jet Dry Powder Inhaler (Dpi) Platform For The Delivery Of High Dose Aerosolized Powder To Infants, Connor Howe

Theses and Dissertations

The goal of this research project was to develop an infant air-jet dry powder inhaler (DPI) platform for high-efficiency nose-to-lung (N2L) aerosol administration to infants through optimization of individual system components followed by expansion of the system to higher doses and different formulations using a new approach. Primary challenges associated with aerosol delivery to infants using the N2L route include the extremely narrow extrathoracic airways, short inspiratory times (~0.2 sec), low safe airway pressure (H₂O), and very low volumes of air (~10 mL) available to form the aerosol. The infant air-jet DPI system was comprised of three main …

Effects Of Titanium And Cerium Addition On Grain Size And Mechanical Properties Of Ductile Iron Castings, Shelton F. Fowler Iv

College of Graduate Studies: Theses & Dissertations

According to the Hall-Petch equation, the refinement of grains in metals increases the yield strength of the material. Austenite grain size influences the fineness of microstructural constituents in the ferrous alloys. It is well studied that cerium and titanium refine the austenite in steels and some gray irons, but no studies have been done to systematically explore the effects of cerium and titanium additions on austenite in ductile iron. This study sought to determine the effects of selected levels of these elements on the grain size within ductile iron. A hypoeutectic iron was chosen for testing as the proeutectic phase …

Determining Cause Of Failure For Load Cells Supporting Vertical Pressure Vessels Subject To Wind Loading, Seth Nowak

College of Graduate Studies: Theses & Dissertations

Wind loads cannot be avoided during a natural disaster such as a hurricane and could affect the strength and stability of vertical pressure vessels during exposure. Vertical pressure vessels cater to large wind loads; therefore, it is imperative to study the effect of additional loading on the structures. In this study, three pressure vessels with volumes of 50 CuFt, 200 CuFt, and 1100 CuFt, supported by three equidistant load cells under their legs are individually analyzed to determine von mises stress to estimate yield failure criteria. Two load rating criteria, maximum load capacity and water-filled condition (critical condition) are utilized …

Investigations Of The Low Temperature Combustion Regions And Emissions Characteristics Of Aerospace F24 In A Constant Volume Combustion Chamber And A Common Rail Direct Injection Ci Engine, Richard C. Smith Iii

College of Graduate Studies: Theses & Dissertations

A study was conducted to investigate the low temperature combustion (LTC) regions of aerospace F24 and ULSD in the static setting of a CVCC and the dynamic setting of a CRDI research engine. This research is conducted to reduce in-cylinder emissions by understanding and implementing a technique to achieve an extended LTC. Emissions data for this study were collected during the operation of the CRDI research engine with a MKS 2030 FTIR and an AVL Microsoot 483. The parameters researched within the static setting of the CVCC included the determinations of the cool flames and NTC regions within the LTHR …

Comparison Of Maintenance Cost Of Medium And Heavy-Duty Alternative Fuel And Diesel Vehicles, Isaac C. Boyce

Graduate Theses, Dissertations, and Problem Reports (ETD)

Abstract

Comparison of Maintenance Cost of Medium and Heavy-Duty Alternative Fuel and Diesel Vehicles

Isaac Boyce

This study was conducted to provide an in-depth analysis of the differences in maintenance cost with the use of alternative fuel and diesel in medium (MD) and heavy-duty (HD) vehicles. With the push toward lower emissions from transportation vehicles for a cleaner future, the United States of America (US) has incentivized the conversion from the use of conventional fossil fuel, diesel, to lower carbon alternatives. With the increased potential for the use of alternative fuels, an investigation is warranted to understand the differences. This …

Magneto-Exothermic Catalytic Chemical Reaction Along A Curved Surface, Muhammad Ashraf, Uzma Ahmad, Saqib Zia, Rama S. R. Gorla, Amnah S. Al-Johani, Ilyas Khan, Mulugeta Andualem

Faculty Publications

In the current study, the physical behavior of the boundary layer flows along a curved surface owing exothermic catalytic chemical reaction, and the magnetic field is investigated. The mathematical model comprised of a part of momentum, energy, and mass equations, which are solved using a finite difference method along with primitive variable formulation. Numerical solutions, using the method of quantitative differentiation, are made with the appropriate choice of dimensionless parameters. Analysis of the results obtained shows that the field temperature and flow of fluids are strongly influenced by the combined effects of catalytic chemical reactions and the magnetic field. The …

Mathematical Model Of The Efficiency Of Investments Aimed In The Implementation Of Water-Saving Technologies

Irrigation and Melioration

In Uzbekistan, research work is being carried out aimed at improving the economic mechanisms for the introduction of water-saving technologies for irrigating agricultural crops. At the same time, the issues related to the analysis of the effectiveness of the use of water-saving technologies when irrigating cotton, the development of mathematical methods for assessing the effectiveness of investments, as well as their introduction into practice have not been sufficiently studied. This article provides a mathematical model of the efficiency of investments aimed at introducing water-saving technologies. The results of a numerical experiment of a mathematical model show that the introduction of …

Efficient Use Of Water Resources In The Basins Of Small Rivers, F. Gapparov, M.F. Gafforova

Irrigation and Melioration

The article provides a recommendation for the efficient use of water resources in the basins of small foothill rivers. The research was carried out on the example of the Govasay river basin located in the northern part of the Fergana Valley. The efficiency factor of the canal has been determined and a technical assessment has been given for the management of water resources in the river basin; the efficiency of the canal is 65-75%. A program for the operational management of water resources in The Govasay river basin and a GIS map of water consumers in the Govasay river basin …

Model Of Groundwater Level Control Using Horizontal Drainage, A. Arifjanov, M. Otaxonov, Z. Abdulkhaev

Irrigation and Melioration

The article describes the main factors affecting the rise in the level of groundwater in the city of Fergana and ways to eliminate them. Currently, in order to reduce the negative impact of rising groundwater levels on the environment, crops, buildings and structures, as well as underground utilities, it is proposed to design horizontal drainage in urban areas and a mathematical model has been developed for changing the groundwater level. For this, long-term data from observation wells were analyzed and the hydraulic parameters of horizontal drainage were selected taking into account the hydrogeology of the area. Taking into account the …

Results Of Proximate Analysis Of Energy Use Of Municipal Solid Waste, N.N. Abduganiev

Irrigation and Melioration

In the modern industrialized world, various raw materials are processed and used for human consumption. While some of the raw materials are converted into the desired product, the rest is thrown into the environment as waste. It is known that solid waste is a type of biomass that is formed in the course of human life. The article presents the results of a preliminary analysis of studies on the use of solid waste energy in the Urta-Chirchik district of the Tashkent region. Sorting results showed that the total volume of municipal solid waste in the district consists mainly of wood …

Shredding Of Cotton Stalks Under The Action Of Toothpicks In A Combined Unit, B. Khudayarov, U. Kuziev, B. Sarimsakov, М. Kholbutaev

Irrigation and Melioration

The article presents materials devoted to the justification of the parameters of the crown-wheel of the combined aggreagate. The technological process of work and the design of the working part, which is crushed by crushing cotton stalks, without breaking them, laying them on the movement of the unit, has been substantiated and developed. The optimal parameters of the crown-wheel and the tooth are determined by solving the regression equations that determine the optimal values of the vertical load on the teeth and its working quality. The results of theoretical and experimental research show that the amount of crushing of cotton …

Influence Of Electrophysical Methods On The Processes Of Root Formation Of Grapes, N.M. Markayev

Irrigation and Melioration

The article describes the possibilities of electrophysical processing before planting cuttings during vegetative cultivation of grape seedlings. The processes of root formation in cuttings using the electrophysical method in the article Acceleration of the process of root formation in cuttings of black raisins, treated at 71 V/m and an electric field strength of 15 hours, and an increase in the viability, quality, growth and survival of rooted seedlings up to 16.67-34% Presented the results of experiments on the increase and methods of electrotechnological processing of grape cuttings. The result of the study is the analysis and results of the processes …

Conditions, Criteria And Principles For Creating An Agri-Cultural Land Market In Uzbekistan, A.R. Nurnazarov

Irrigation and Melioration

The article analyzes the prerequisites for creating a market for agricultural land in the Republic of Uzbekistan, special attention is paid to land reform, land degradation (reduction of the bonitet score from 60 in 1991 to 50 or more at present, pasture degradation by 20-30%) and increase in economic from their use, the role of land rent in payments for land. 6 basic principles for creating a land market have been established and systematized, the relationship between X-rays and water in the irrigated farming zone, the role of the market in increasing the efficiency and effectiveness of the use of …

Economic Assessment Of The Effect Of Family Income On Students' Disciplines, Sh.A. Muratov

Irrigation and Melioration

The importance of higher education in scientific research, its role in poverty reduction and population growth has been studied theoretically. Also, when using the data of social surveys conducted by 538 respondents (students) studying in higher education institutions, they were awarded the Order of the logistics regulator in the economic assessment of the factors influencing the rate of mastery of disciplines. Factors influencing the acquisition of subjects by students: the main income of the family comes from non-farm (69,9 %), sex (52,2 %), studying at a higher education institution on a state grant (108,8 %), the student's course of study …

Innovative Rotor Casing And Leveling Apron For Combined Tillage Machine, A.A. Akhmetov, L.B. Muratov

Irrigation and Melioration

Investigations of the design of a combined machine equipped with an innovative casing and a leveler apron are presented, and the parameters of the leveler apron are substantiated. It was experimentally established that when the height of the drawing prism is exceeded by more than 200 mm, due to the falling of the crumbling part of the soil onto the rotor, the soil is thrown forward in the direction of the machine. Therefore, to eliminate soil waste, it is necessary either to reduce the height of the drag prism, or to increase the distance between the rotor and the leveling …

Ensuring The Uniformity Of Movement Of The Working Bodies Of The Machine For Processing Ridges In The Depth Of Travel, А. Tukhtakuziev, K.G. Abdulkhaev

Irrigation and Melioration

The article theoretically investigates the issue of identifying ways to ensure the deepening of the working bodies of the machine for processing ridges to a given processing depth and its required uniformity of stroke. The research results show that the deepening of the working bodies of the ridges processing machine to a given processing depth and its required uniformity is provided mainly due to the correct choice of the vertical distance from its reference plane to the lower connection points. The novelty of the conducted research lies in the fact that an analytical dependence has been obtained that allows us …

Develepment Of Land Market In Eastern European Countries And Experience For Uzbekistan, A.R. Nurnazarov

Irrigation and Melioration

The article examines the experience of the formation of the agricultural land market in Eastern European countries since the 90 s of the twentieth century, the problems and features of its devel-opment, the impact of the land market on the economies of countries. Particular attention is paid to the transformation of land ownership, methods of land privatization, land pricing, restrictions on land purchase, regulation of land relations in market conditions, issues of granting the right to pur-chase land to foreign individuals and legal entities, requirements for land owners for the presence of a special agricultural education or 3-5 years of …