Engineering Science and Materials Commons^™

Increasing The Efficiency Of Water Distribution Management When Operating Pumping Stations Of The Irrigation System, O.Y. Glovatsky, R.R. Ergashev, B. Hamdamov, N.M. Ismailov, B.T. Kholbutaev

Irrigation and Melioration

The article is to control the parameters of the unsteady movement of water in the canals and the pumping station, which ensure the maintenance of the specified operating modes of the pumping stations under non-stationary conditions. To achieve this goal, it is necessary to solve the problems of coordinating the operating modes of the units of the head pumping station (PS) with the operating modes of the partitioning structures in the conditions of emptying and filling the ponds of the main canal with water. The article discusses the implementation of the method of water distribution control on the mathematical model …

Analysis Of Theoretical And Natural Field Studies Of Reservoir Silling, A.M. Arifjanov, F. Gapparov, T.U. Apakhujayeva, S.N. Xoshimov

Irrigation and Melioration

The article developed a mathematical model of the processes of siltation of reservoirs, taking into account the energy state of the flow, and proposed a calculation method. In the process of siltation of the reservoir, the dependence of the volume on the change in the water level in the reservoir was estimated. On the basis of studies carried out in full-scale field conditions, the recommended calculation method is comparatively evaluated and analyzed. Field studies were carried out in the Chimkurgan, Tashkent and Yuzhno-Surkhan reservoirs. A relationship is obtained that expresses the dependence of the relative volume of siltation of the …

Planed Dimension Of Flow Deformed By A Single Dam That Is Impermeable To Water From The Body, M.R. Bakiev, K.T. Yakubov, I.J. Asamatdinov

Irrigation and Melioration

Coastal erosion is a type of water erosion that causes significant damage to the national economy each year: leaching of overland coastal crops, failure of protective dams, destruction of irrigation canals, dilapidated buildings and structures, among others. To combat leaching, cross-dams are used which are waterproof and water-permeable. The aim of this work was to develop a method for calculating the planned dimension of compressed flow with a transverse dam, which included comparing the lengths of the upper and lower tilt zones, the boundaries of individual zones and the results of research in the laboratory and in nature. According to …

Research Of Energy Indicators Of Electric Drives With Frequency Converters (Frequency Converters) On The Operating Equipment Of Cotton Cleaning Plants, A.J. Isakov, B.K. Tukhtamishev, J.N. Tolipov

Irrigation and Melioration

The article deals with the theoretical and practical substantiation of the replacement of an unregulated electric drive of the main technological equipment of cotton refineries with a frequency-controlled electric drive. The influence of a change in the load on the motor shaft on the main parameters of the steady state is considered. In an asynchronous motor, with an increase in the load, slip increases to such a value at which the torque of the motor balances the increased moment of resistance. Considering that when the stator slip resistance is less than the critical one is a small fraction of the …

Stabilization Of Discharge Processes Involved In Electrical Fields Of Electrostatic Precipitators, Sh.M. Muzafarov, B.N. Erkinov, A.I. Pardaev, V.E. Baliskiy, B.К. Tаgaev

Irrigation and Melioration

The article provides information on achievements in the field of electrical gas cleaning. A critical analysis of the principle of operation of the electrostatic precipitators developed and currently in operation is carried out. The possibility of increasing the efficiency of electrical gas cleaning using unipolar voltage pulses is analyzed. A theoretical analysis of the processes in the discharge gap was carried out using the existing theory of electric discharges in gases. Based on the analysis of the data, the discharge mechanism is established in a sharply inhomogeneous electric field at a pulsed voltage. It is established that when using voltage …

Determination Of The Rational Values Of The Parameters Of The Disc Rollers Of The Combined Unit, A.K. Igamberdiev, D.K. Muqimova

Irrigation and Melioration

In our country, repeated crops are sown in newly plowed lands. In such conditions, the use of combined units that perform several technological operations simultaneously in one pass is considered effective. However, due to the inadequacy and validity of the parameters of the working bodies for the quality of pre-sowing tillage in newly plowed lands, there is an increase in the number of passes, fuel consumption, loss of soil moisture and other costs and, as a result, the possibility of timely sowing and friendly germination of repeated crops is reduced . The rational parameters of the new design of disk …

Autonomous Photovoltaic System For Year-Round Guarantee Supply Of Electricity To Rural Facilities, M.N. Tursunov, Х. Sabirov, U.R. Kholov, Т.Z. Аkhtamov

Irrigation and Melioration

The article discusses the physical and technical features of the experimental results of studying the parameters of an autonomous photovoltaic station (AFES) with a power of 2600 W designed and manufactured on the basis of 16 photovoltaic batteries made of polycrystalline silicon with an efficiency of 15.6 %. It is shown that an autonomous photovoltaic efficiently and reliably provides electric energy a lighting system for car parking in the winter season (January and February) and it is planned to lift water from a well with a depth of 70-80 m for irrigation and maintenance of the Heliopoligon from April 2020. …

Enhanced Optical Propulsion And Material Analysis For Multiple Rayleigh Particles, Christopher Alan Jones

Student Theses and Dissertations

Studies have shown that materials exhibiting specific attributes can be propelled forward by photons of varying wavelengths within the visible light spectrum. This is enhanced by a momentum reversal due to the wave scattering of ejected electrons. Research has indicated that these effects are due to a particle's size and shape. Furthermore, these effects can lead to a tunability within cylinders/rods. The present research aims to provide an approximate macroscopic solution using Rayleigh theory to assess single and multiple particle forces for both ideal and causal systems. The forces are acquired through the integration of the Minkowski stress tensor just …

The Concept Of The Mathematical Description Of The Multi-Coordinate Mechatronic Module Of The Robot, Temurbek Omonboyevich Rakhimov

Acta of Turin Polytechnic University in Tashkent

The article deals with the concept of mathematical de- scription of multi-coordinate mahatronic modules of robots. The main results of the work are a generalized structure of a multi- coordinate mechatronic module of motion, a kinematic diagram of an electromagnetic multi-coordinate mechatronic module with three independent coordinate linear and angular movements is proposed, consisting of four electromagnets, controlled couplings designed to transmit the reciprocating motion of the moving parts of electro- magnets to the output rods and a cable, which are associated with the links of work and bringing them into linear and angular mo- tion. A simulation model of …

Preparation Characterization And Tribological Behavior Of Lube Oil With Nanoparticles Additives, Waleed Alghani

Student Works (2020-2029)

There are many companies worldwide that would like to improve and upgrade the lube oil and enhance its performance. There is a big concern for the enhancement of lube oil by using nanotechnology and more precisely with using nanomaterial additives. Much work has made to explore and develop new sorts of lubricating oil nano-additives to diminish wear and friction in tribological configurations and to enhance surface morphology. It has noted that the use of dual nano-additives should examine the lubricating capacity and durability of lubricant. (TiO2 Anatase + Graphene) and (ZnO + Graphene) nanoparticles have selected to formulate nano-additives that …

An Affordable And Portable Palpable System For Sensing Breast Tissue Abnormalities, Cody J. Clarke

Montview Journal of Research & Scholarship

Due to the high cost of equipment and lack of trained personnel, manual palpation is a preferred alternative breast examination technique over mammography. The process involves a thorough search pattern using trained fingers and applying adequate pressure, with the objective of identifying solid masses from the surrounding breast tissue. However, palpation requires skills that must be obtained through adequate training in order to ensure proper diagnosis. Consequently, palpation performance and reporting techniques have been inconsistent. Automating the palpation technique would optimize the performance of self-breast examination, optimize clinical breast examinations (CBE), and enable the visualization of breast abnormalities as well …

Me-Em 2019-20 Annual Report, Department Of Mechanical Engineering-Engineering Mechanics, Michigan Technological University

Department of Mechanical and Aerospace Engineering Annual Reports

Table of Contents

• Element 1
• Element 2
• Element 3
• Element 4
• Enrollment & Degrees
• Graduates
• Department
• Alumni
• Donors

Fatigue Of A Sic/Sic Ceramic Composite With An Ytterbium‐Disilicate Environmental Barrier Coating At Elevated Temperature, Marina B. Ruggles-Wrenn, Thaddeus M. Williams

Faculty Publications

Excerpt: Tension-tension fatigue performance of a SiC/SiC composite with an ytterbium-disilicate environmental barrier coating (EBC) was investigated at 1200°C in air and steam. The composite is reinforced with Hi-Nicalon™ SiC fibers and has a melt-infiltrated matrix processed by chemical vapor infiltration of SiC with subsequent infiltration with SiC particulate slurry and molten silicon. Abtract © American Ceramic Society

Effect Of Motor-Assisted Elliptical Training Speed And Body Weight Support On Center Of Pressure Movement Variability, Farahnaz Fallahtafti, Chase M. Pfeifer, Thad W. Buster, Judith M. Burnfield

Department of Mechanical and Materials Engineering: Faculty Publications

Background: A motor-assisted elliptical trainer is being used clinically to help individuals with physical disabilities regain and/or retain walking ability and cardiorespiratory fitness. Unknown is how the device’s training parameters can be used to optimize movement variability and regularity. This study examined the effect of motor-assisted elliptical training speed as well as body weight support (BWS) on center of pressure (CoP) movement variability and regularity during training. Methods: CoP was recorded using in-shoe pressure insoles as participants motor-assisted elliptical trained at three speeds (20, 40, and 60 cycles per minute) each performed at four BWS levels (0%, 20%, 40%, and …

Me-Em Enewsbrief, September 2020, Department Of Mechanical Engineering-Engineering Mechanics, Michigan Technological University

Department of Mechanical and Aerospace Engineering eNewsBrief

No abstract provided.

Recent Progress In Bifunctional Catalysts For Zinc-Air Batteries, Neng-Neng Xu, Jin-Li Qiao

Journal of Electrochemistry

Zinc-air battery has attracted great attention from researchers due to its high energy density and power density, which is expected to be widely used in energy conversion and storage. Air electrode as the core area of oxygen catalytic reaction is the focus of the entire zinc-air battery research. Recently, many research achievements have been made in non-noble metal bifunctional catalysts/electrodes with high activity, low cost and abundant species. In this review, we mainly focus on the reaction mechanism and the recent progress in non-noble metal oxide catalyst, carbon-based catalyst, and carbon-based transition metal compound composite and self-supporting electrode. In addition, …

Research Progress Of Metal-Nitrogen-Carbon Catalysts Toward Oxygen Reduction Reaction Inm Changchun Institute Of Applied Chemistry, Ming-Jun Xu, Jie Liu, Jun-Jie Ge, Chang-Peng Liu, Wei Xing

Journal of Electrochemistry

The development of highly active and stable catalysts toward oxygen reduction reaction (ORR) has been facing severe challenges. In recent years, pyrolytic M-N-C catalysts and metal-organic framework derived materials made the performance of non-noble metal catalysts greatly improved, however, the molecular and atomic level understanding in the reaction active sites and the mechanism are still lacking. Here, we summarize the recent research progress made in the Changchun Institute of Applied Chemistry. We present a microporous metal-organic-framework confined strategy toward the preferable formation of ORR catalysts. Firstly, we studied the active site and proposed a new active site structure for the …

Electrochemical Carbon Dioxide Reduction In Flow Cells, Jia Fan, Na Han, Yan-Guang Li

Journal of Electrochemistry

Electrochemical carbon dioxide reduction (CO₂RR) is an appealing approach to convert atmospheric CO₂ to value-added fuels and industrial chemicals, and may play an important role during the transition to a carbon-neutral economy. In order to make this technology commercially viable, it is essential to pursue CO₂RR in flow reactors instead of conventional H-type reactors, and to combine electrocatalyst development with system engineering. In this review, we overview the cell configurations and performance advantages of the two types of flow reactors, analyze their shortcomings, and discuss the effects of their different components including gas diffusion electrode …

Electrolyte Tailoring For Electrocatalytic Reduction Of Stable Molecules, Jin-Han Li, Fang-Yi Cheng

Journal of Electrochemistry

Reduction of stable molecules such as CO₂ and N₂ is important process in electrochemical energy conversion and storage technologies for electrofuels production. However, for the inert nature of CO₂/N₂ molecule and competitive proton reduction in conventional aqueous electrolytes, selective electrochemical carbon/nitrogen fixation suffers from high overpotential, low reaction rate and low selectivity. While addressing these issues has witnessed substantial advances in electrocatalysts, much less attention has been placed on the electrolytes, which play an important role in regulating the local environment and thus the performance of catalysts under operating conditions. Rational design of electrolytes has …

Fuel Cell Performance Of Non-Precious Metal Based Electrocatalysts, Yan-Feng Zhang, Fei Xiao, Guang-Yu Chen, Min-Hua Shao

Journal of Electrochemistry

The commercialization of proton exchange membrane fuel cells (PEMFCs) is hindered by high cost and low durability of Pt based electrocatalysts. Developing efficient and durable non-precious metal catalysts is a promising approach to addressing these conundrums. Among them, transition metals dispersed in a nitrogen (N)-doped carbon support (M-N-C) show good oxygen reduction reaction activity. This article reviews recent progress in M-N-C catalysts development, focusing on the catalysts design, membrane electrode assembly fabrication, fuel cell performance, and durability testing. Template-assisted approach is an efficient way to synthesize M-N-C materials with homogeneously dispersed single atom active site and reduced metal particles, carbides …

Electrochemical Energy Storage And Conversion Based On Organic Electrodes, Jian-Hang Huang, Xiao-Li Dong, Zhao-Wei Guo, Yuan-Yuan Ma, Yan-Rong Wang, Yong-Gang Wang

Journal of Electrochemistry

Aqueous batteries have been considered to be a competitive candidate for large-scale energy storage. However, most of aqueous batteries adopt inorganic electrode materials with metallic elements, which are based on the reversible insertion of metal ions, making their application being highly hindered by limited cycle life, environmental issue, high cost and low reserves. On the other hand, organic electrode materials offer the advantages of abundant reserves, tunable structures, renewability and environmental benignity. Furthermore, the wide internal space enables these organics to flexibly store various charge carriers. Organics have been investigated as the alternative to inorganic electrode materials. Herein, we review …

Recent Progress On Enhancing Effect Of Nanosized Metals For Electrochemical Co2 Reduction, Yu-Ning Zhang, Dong-Fang Niu, Shuo-Zhen Hu, Xin-Sheng Zhang

Journal of Electrochemistry

The electrochemical conversion of CO₂ to chemical raw material for further utilization shows promising future to alleviate global warming and realize carbon cycle in nature, which is of great significance to the green chemistry and sustainable development. This review briefly introduces the advantages of CO₂ electrochemical reduction (CO₂ER) and its basic reaction principles, and summarizes the recent progress in a series of activity enhancement strategies based on nanosized metal catalysts. The influences of alloy effect, interface engineering, synergistic effect, surface defect engineering and support effect on the catalytic performance of nanosized metals for CO₂ER …

Performance Of Pld Grown Zno Thin Film As A Thin Film Transistor, Shahidul Asif

Graduate Theses/Dissertations

The performance of ZnO thin film (grown in different parameters) as a thin film transistor (TFT) is the focus of this study. ZnO is renowned for being n-type semiconductor naturally which was utilized in fabricating a thin film transistor here. This thesis is compared the performance of ZnO thin film transistor by growing the thin film using pulsed laser deposition (PLD) on two slightly different substrates at different temperatures in an optimal 0.1 milli bar oxygen pressure which was later analyzed using other material characterization methods. The substrates were both Si (100) but had different resistivity due to different amount …

A Framework For Using Fused Image Data In Statistical Process Control, Shengfeng Chen

Dissertations

The use of image data in manufacturing quality control systems has grown rapidly over the years. Technological advancements in imaging devices (e.g., digital cameras, x-ray scanners, infrared cameras) have provided convenient and cost-effective ways to obtain images. These images contain important quality features (e.g., textures and product dimensions) that can be used to monitor, diagnose, predict, and control manufacturing processes. A key tool for monitoring images is statistical process control charts. Integrating images of parts to detect process shifts can significantly improve a quality systems efficiency. Unfortunately, appropriate techniques that take full advantage of data-rich images for control charting are …

Physical Behavior Of Thermally Affected Bronze And Brass, Samiul Kaiser, Mohammad Salim Kaiser

Journal of Mechanical Engineering Science and Technology (JMEST)

The physical behavior of thermally affected cast copper, aluminum bronze and brass has been studied by subjecting to heating isochronally for one hour at a range of 600°C. It shows that solid-solution hardening takes place into the Al added bronze and Zn added brass metal. Due to heating Al forms hard and brittle intermetallic of copper aluminates into the bronze metal which responses some age-hardening effects. The electrical conductivity of the metals increases initially through heat treatment due to stress relieving and finally decreases due to formation of intermetallic precipitates. The color of the heated samples are also studied through …

The Influence Of The Reference Area Of Aileron On The N2xx Aircraft Using Computational Fluid Dynamics, Siti Nur Rahmah, Gaguk Jatisukamto, Hary Sutjahjono

Journal of Mechanical Engineering Science and Technology (JMEST)

Aileron is a control surface that functions as a regulator of roll motion. The movements of the ailerons are opposite to the left and right sides. Previous studies have shown that graphs of hinge moment coefficient (Chm) values increases with increasing angle of attack. This study is to determine the aerodynamic characteristics of aileron by combining the surface area of the vane into the aileron by varying the aileron’s deflection. The calculation is performed using a numerical method in two dimensions (2D) commercial CFD simulation software. The results of the study concluded that the hinge moment coefficient for modified airfoil …

Hardness Evaluation On Ss 316l Joined With Gas Tungsten Arc Welding Under Constant Heat Treatment, Duwi Leksono, Imam Sudjono

Journal of Mechanical Engineering Science and Technology (JMEST)

The purpose of this study is to show the hardness of the GTAW welding results on SS 316L metal with surface heating during the welding process. Observations in this study used SS 316L material with heat temperature regulation on the metal surface of the welding process using heating variations of 100 ℃, 120 ℃ and 140 ℃. The welding process of SS 316L material used a welding joint model uses single V-type welding joint with an angle of 60°, a spacing of 2 mm, a root surface of 1 mm and a thickness of 5 mm. Vickers hardness test was …

The Effect Of Heat Treatment To The Erosion Rate Of Brass Composite, Aminnudin Aminnudin, Solichin Solichin

Journal of Mechanical Engineering Science and Technology (JMEST)

Brass composites can be improved their mechanical properties by the heat treatment process. The improvement of the mechanical properties of this technique is expected to increase the resistance of the composite to erosion that occurs in the environment of flow water. Brass composites used are compositeswith fly ash 5, 10, 15, and 20%. The heat treatment process was carried out using electric furnace withoutprotective gas. Composite heat up to 350°C and 400°C for 30 min. and quenching with water. Before and after the erosion test, the weight of the test specimen was weighed with analytical scales. The treatment process affects …

Performance Enhancement Of Shell And Tube Heat Exchanger On Parallel Flow With Single Segmental Baffle, Avita Ayu Permanasari, Poppy Puspitasari, Sukarni Sukarni, Retno Wulandari

Journal of Mechanical Engineering Science and Technology (JMEST)

The shell and tube heat exchanger was a tool to exchange the heat energy between fluids with different temperatures that occurred through direct or indirect contact. The energy exchange in fluids could be occurred with the same phase (liquid to liquid or gas to gas) or two fluids with different phase. To date, the process of heat transfer in the industrial field was crucial in machine work. Therefore, there were studies directed to optimize and develop the function and thermal performance of a heat exchanger by adding Baffles to the side of the shell. Vortex flow that occurs with the …

The Effect Of Solution Treatment Temperature And Quenching Media Variation In Heat Treatment Process Cu-Zn-Al Shape Memory Alloys On Shape Memory Effect And Microstructures, Wikan Jatimurti, Monica Gayatri K, Mavindra Ramadhani, Rochman Rochiem

Journal of Mechanical Engineering Science and Technology (JMEST)

Shape memory alloys (SMAs) are metal alloys with a reversible ability to recover their shape at a certain temperature after being deformed. This ability referred to as Shape Memory Effect (SME). The application of SMAs such as Ni-Ti and Cu-Zn-Al alloys usually used on automotive, biomedical, etc. The commonly used SMA is Ni-Ti because of its superior SME properties than Cu-Zn-Al, even though the price is quite higher. The SME of Cu-Zn-Al might be improved by increasing the presence of the martensite phase in its microstructure by heat treatment. The heat treatment process given to Cu-21Zn-5Al alloy is a homogenizing, …