Engineering Science and Materials Commons^™

Experimental Study On The Tribo-Chemical Smoothening Process Between Self-Mated Silicon Carbide In A Water-Lubricated Surface-Contact Reciprocating Test, Le Jin, Herbert Scheerer, Georg Andersohn, Matthias Oechsner, Dieter Hellmann

Friction

Silicon carbide (SiC) can be tribo-chemically smoothened during a self-mated sliding procedure in the aqueous environment. As well reported in the point-contact tests, this smoothening process works well due to the abundant water as oxidant. After this smoothening process, the tribo-surface is well polished, a closely mated tribo-gap naturally forms, and an ultra-low friction state is built. However, water in the tribo-gap could be insufficient in industrial applications, e.g., the seal gap in mechanical seals. In this study, the tribo-chemical smoothening behavior in such environment was researched. A surface-contact reciprocating test was used to simulate the aqueous environment where water …

Water-Based Superlubricity In Vacuum, Chen Xiao, Jinjin Li, Lei Chen, Chenhui Zhang, Ningning Zhou, Tao Qing, Linmao Qian, Jiyang Zhang, Jianbin Luo

Friction

This study achieved water-based superlubricity with the lubrication of H3PO4 solution in vacuum (highest vacuum degree <10-4 torr) for the first time by performing a pre-running process in air before running in vacuum. The stable water-based superlubricity was sustainable in vacuum (0.02 torr) for 14 h until the test was stopped by the user for non-experimental factor. A further analysis suggested that the superlubricity may be attributed to the phosphoric acid-water network formed in air, which can efficiently lock water molecules in the liquid lubricating film even in vacuum owing to the strong hydrogen bond interaction. Such capability to lock water is strongly affected by the strength of hydrogen bond and environmental conditions. The realization of water-based superlubricity with H3PO4 solution in vacuum can lead to its application in space environment.

Tribological Performance Of Novel Nickel-Based Composite Coatings With Lubricant Particles, Ignacio Tudela, Andrew J. Cobley, Yi Zhang

Friction

The present study is focused on the evaluation of the tribological performance of novel Ni/hBN and Ni/WS2 composite coatings electrodeposited from an additive-free Watts bath with the assistance of ultrasound. Lubricated and non-lubricated scratch tests were performed on both novel composite coatings and on standard Ni deposits used as a benchmark coating to have an initial idea of the effect of the presence of particles within the Ni matrix. Under lubricated conditions, the performance of the Ni/hBN composite coating was very similar to the benchmark Ni coating, whereas the Ni/WS2 behaved quite differently, as the latter did not only show …

Numerical Analysis Of Time-Varying Wear With Elastic Deformation In Line Contact, Wanglong Zhan, Ping Huang

Friction

Wear is an important factor for failures of mechanical components. Current research on wear is mainly focused on experiments while the numerical simulation of wear is hardly used owing to the complexities of the wear process. Explaining the effect of friction on the wear process is important, as it will lead to a deeper understanding of the evolution of wear. This study proposed a numerical method to expound the wear process in the contact between an elastic cylinder and a half-space simulating the ring-block tester. There are two difficulties during the calculation; one is that the contact shapes vary with …

Optimal Control Of Active Nematics, Michael M. Norton, Piyush Grover, Michael F. Hagan, Seth Fraden

Department of Mechanical and Materials Engineering: Faculty Publications

In this work we present the first systematic framework to sculpt active nematic systems, using optimal control theory and a hydrodynamic model of active nematics. We demonstrate the use of two different control fields, (i) applied vorticity and (ii) activity strength, to shape the dynamics of an extensile active nematic that is confined to a disk. In the absence of control inputs, the system exhibits two attractors, clockwise and counterclockwise circulating states characterized by two co-rotating topological þ1 2 defects. We specifically seek spatiotemporal inputs that switch the system from one attractor to the other; we also examine phase-shifting perturbations. …

Microfluidic Systems With Embedded Cell Culture Chambers For High Throughput Biological Assays, Arian Jaberi, Amir Monemian Esfahani, Fariba Aghabaglou, Jae Sung Park, Sidy Ndao, Ali Tamayol, Ruiguo Yang

Department of Mechanical and Materials Engineering: Faculty Publications

The ability to generate chemical and mechanical gradients on chips is important both for creating biomimetic designs or enabling high-throughput assays. However, there is still a significant knowledge gap in the generation of mechanical and chemical gradients in a single device. In this study, we developed gradient-generating microfluidic circuits with integrated microchambers to allow cell culture and to introduce chemical and mechanical gradients to cultured cells. A chemical gradient is generated across the microchambers, exposing cells to a uniform concentration of drugs. The embedded microchamber also produces a mechanical gradient in the form of varied shear stresses induced upon cells …

A New Technical Solution For Cleaning The Water Intake Structure Of Pumping Stations From Siltation And Its Experimental Research, M.M. Mukhammadiev, S.R. Juraev

Irrigation and Melioration

The article considers one of the most pressing problems of pumping stations in the irrigation system today, their blurring of the bottom of the water intake (avancamera and water intake chambers), analyzes the existing proposals, designs and technical solutions and their advantages and disadvantages. Given the above advantages and disadvantages, a new design has been proposed for the treatment of water intake structures from turbid sediments with minimal energy and capital expenditures, very cheap and simple to operate and reliable. The design includes a turbid suction pump and a turbid pump, as well as a pulp pipeline. The pressurized water …

Assessing Surface Water Features Using Landsat-8 Oli And Sentinel-1 Satellite Images Case Study Sirdaryo Region, S.M. Muratov, Kh.A. Abdivaitov, Sh.F. Rahmatillayev

Irrigation and Melioration

Water resources have become a very big problem in every part of Uzbekistan for several decades. Water is used not only exclusively for agricultural development, but also for many other purposes, such as industrial and chemical activities. Therefore, it is important to study the properties of surface water objects using optical and microwave satellite images. The Syrdarya region was selected for research. Because in the past, there have been no studies of water bodies using satellite images. The article presents the results of studies on the assessment of water properties from optical and microwave satellite images. In research for optical …

Distribution Of Pressure And Specific Energy In The Twirled Stream For Confusor, A.A. Yangiev, D.S. Adjimuratov

Irrigation and Melioration

Article brings up the advantage of confusor part application in outflow part of vortex spillway, which may be more rational from the point of view of providing non-cavitation operation of flow swirler. Analytical design method and program developed is given of pressure and specific energy for aerated part of swirled flow in vortex spillway confusor part, which match with experimental results, it allows for fast and quite accurate realization of distribution analysis for pressure and specific energy in swirled flow along the length of the confusor for various rates of taper.

Economic Assesment Of The Impact Of Climate Factors On Wheat Yield In Samarkand Region, Sh.B. Babakholov

Irrigation and Melioration

Agricultural production is highly vulnerable to climate shocks and predicted climate consequences may pose severe challenges to the resilience of Uzbek agricultural system, especially in terms of food security and income stability of rural producers. In this context, present study proposed to assess the impact of climate factors, such particular changes in mean temperature and rainfalls on total output of wheat-cultivating farmers in Samarkand region. By considering irrigation source and heterogeneous geography of the region, farmers engaged in wheat production were analyzed in two: upstream and downstream zones using Fixed effect panel approach. The empirical findings of study revealed that, …

Change In Level Water In Pumping-Plant Intake, R.R. Ergashev, B.T. Xolbutayev

Irrigation and Melioration

A decrease in the water level in the pump chamber of the pumping stations leads to the formation of whirlpools in front of the suction pipes. As a result of air intake, the pump unit operates in cavitation mode and their intensive wear occurs. As the data obtained from the Karshi machine channel show, mainly a decrease in design water levels in the downstream waters is observed at the first pumping station. Depending on the number of simultaneously operating pumping units, the minimum water level in the head pumping station should be from 4.5 m to 5.7 m. The received …

Modeling The Impact Of Changes In The Ground Water Level On The Stability Of Agricultural Landscapes Using Gis, A.M. Arifjanov, L.N. Samiev, F.K. Babajanov, G.M. Xamdamova, Sh.N. Yusupov

Irrigation and Melioration

The article presents modern GIS methods for determining the stability of changes in irrigated areas and the depth of the ground water level.the most correct solutions are given in modeling this process. To distinguish agricultural landscapes, the classification of agricultural acreage in the lower part of the Amu Darya river region was made using 16-day periodic rasters 2017 of 2018 and the NDIS MOD13Q1 sensor of agricultural acreage, type NDVI. The annual change in the level of underground water in relation to the state of rivers and channels is analyzed. A steady change in agricultural acreage on the right Bank …

Determination And Assessment Of The Spatio-Temporal Changing Dynamics In The Groundwater Level And Mineralization In Irrigated Areas Under Climate Change (As An Example Of Syrdarya Province), S. Khasanov, S. Adilov, R. Kulmatov

Irrigation and Melioration

In the irrigated lands of the Aral Sea Basin, salinization processes are taking place as a result of rising groundwater levels and increasing its mineralization due to the unsustainable use of water and land resources. This, in turn, leads to the withdrawing of arable land and a decrease in crop yields. This is especially the case in the irrigated areas of the lower reaches of the Amudarya and Syrdarya rivers, located in Uzbekistan, southern Kazakhstan, and Turkmenistan. This research was aimed to learn and evaluate the long-term changing behavior of groundwater level and mineralization in the irrigated areas of the …

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. …

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 Engineering-Engineering Mechanics Annual Reports

Table of Contents

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

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 Engineering-Engineering Mechanics eNewsBrief

No abstract provided.

Comparison Of Plantar Pressure Profile Of Young Adults During Training On Elliptical Devices And Overground Walking: A Pilot Study, Guilherme Manna Cesar, Thad W. Buster, Judith M. Burnfield

Department of Mechanical and Materials Engineering: Faculty Publications

Background: Elliptical training may offer advantages over other cardiorespiratory exercises for those requiring podiatric care, since its constant double-limb support diminishes recurring high-impact plantar forces while allowing exercise in a functional, upright posture. Unknown is the impact of distinct elliptical models, that can alter user’s body mechanics, on potential variations in plantar pressure patterns.

Purpose: To compare plantar pressure variables while exercising on four ellipticals and walking.

Methods: For this cross-sectional pilot study, plantar pressure data were recorded from ten young adults while exercising on four ellipticals (True, Octane, Life Fitness, SportsArt) and walking overground. One-way repeated measures ANOVA identified …

Magnetically Induced Carrier Distribution In A Composite Rod Of Piezoelectric Semiconductors And Piezomagnetics, Guolin Wang, Jinxi Liu, Wenjie Feng, Jiashi Yang

Department of Mechanical and Materials Engineering: Faculty Publications

In this work, we study the behavior of a composite rod consisting of a piezoelectric semiconductor layer and two piezomagnetic layers under an applied axial magnetic field. Based on the phenomenological theories of piezoelectric semiconductors and piezomagnetics, a one-dimensional model is developed from which an analytical solution is obtained. The explicit expressions of the coupled fields and the numerical results show that an axially applied magnetic field produces extensional deformation through piezomagnetic coupling, the extension then produces polarization through piezoelectric coupling, and the polarization then causes the redistribution of mobile charges. Thus, the composite rod exhibits a coupling between the …

Open-Source Digitally Replicable Lab-Grade Scales, Benjamin R. Hubbard, Joshua M. Pearce

Michigan Tech Publications

This study provides designs for a low-cost, easily replicable open-source lab-grade digital scale that can be used as a precision balance. The design is such that it can be manufactured for use in most labs throughout the world with open-source RepRap-class material extrusion-based 3-D printers for the mechanical components and readily available open-source electronics including the Arduino Nano. Several versions of the design were fabricated and tested for precision and accuracy for a range of load cells. The results showed the open-source scale was found to be repeatable within 0.05 g with multiple load cells, with even better precision (0.005 …

Influence Of Elements Of Irrigation Equipment On Irrigation Erosion, M.M. Sarimsakov, O.S. Abdisamatov, Z.T. Umarova

Irrigation and Melioration

Irrigation erosion is a process that has a significant negative impact on agricultural production, which leads to a sharp decrease in soil fertility and productivity. The costs associated with growing crops will increase. Today, more than 720,000 irrigated lands in the country suffer from irrigation erosion. Studies have shown that in typical gray soils with a slope of more than 0.30, intensive irrigation of apple orchards leaches 24.6 tons of soil particles per hectare per season. Improved irrigation, that is, a decrease in the leaching of soil particles during irrigation using transverse barriers, was achieved by 6–12%. Irrigation reduces the …

Research Of Water Flow Motion In The Channel Of Amu-Bukhara Machine Channel, D.R. Bazarov, F. Artikbekova, M.P. Tashkhanova, B.M. Norkulov

Irrigation and Melioration

The article considers a numerical study of the movement of a water stream in the channel of the Amu Bukhara Machine Channel (ABMK). Water intake to the inlet canal is carried out from the Amu Darya river in a damless manner, therefore, ensuring the flow of clarified water into the anterior chambers of pumping stations is an urgent task. According to the developed model, consisting of hydrodynamic equations based on the laws of conservation of momentum and mass, data on the dynamics of velocities in the channel of the supply channel ABMK are obtained and zones of uneven flow in …

Irrigation Value The Mechanical Composition River Springs, A.M. Arifjanov, L.N. Samiev, F.K. Babajanov

Irrigation and Melioration

The article studies the influence of the fractional composition of river sediments on the soil structure of irrigated lands and on the process of soil formation. According to surveys in the Mirishkor canal, sediments formed in the river are distinguished by the distribution type in the main canal. The fractional composition of sediments mainly consists of particles of fine sand (0.1-0.05 mm) and coarse dust (0.05-0.001 mm).According to the results of surveys, by studying the mechanical composition of sediment in the channel, it will be possible to observe changes in the amount of composition, such as N-NH4, P2O5, K2O chemicals. …