Mechanical Engineering Commons^™

Efficient Operation Of Direct Coupled Solar Home Pv System: A Case Of Solar Home Pv System Installed In Dodoma, Tanzania, Sarah P. Ayeng'o

Tanzania Journal of Engineering and Technology (TJET)

Direct coupled Photovoltaic (PV) system is a common topology among most of the off-grid communities in the world. This topology has less components hence resulting in low investment costs. However, it suffers much losses when battery operating voltage is far from maximum power point voltage of PV modules. This scenario can be attributed by different factors such as; variation in solar radiation, load profile and temperature. Efficient operation of these systems is required in order to reduce losses. Usually in direct coupled system, PV modules are connected in parallel with batteries through a charge controller hence making PV output to …

Experimental Study On A Hybrid Solar Distillation System Integrated With A Photovoltaic Thermal Collector For The Co-Production Of Electricity And Freshwater, S. A. El Agouz, Mohamed Samy Abo Shala, Ayman Refat Abd Elbar

Journal of Engineering Research

This experimental study investigates the performance of a hybrid solar still system integrated with a photovoltaic (PV) panel and a cooling system, with the goal of enhancing both the freshwater productivity and the performance of the photovoltaic panel. Over a span of four consecutive days, four distinct experimental cases were tested in Tanta (Longitude/Latitude: E 31° 0′/ N 30° 47′), each with different cooling water flow rates of (3 L/min, 6 L/min, and 9 L/min) for cooling the lower surface of photovoltaic panel, and different hot water flow rates of (0.6 L/hr, 0.9 L/hr, and 1.2 L/hr) input to …

Development Of A Drive-Rod Unified Variable Pitch Control Mechanism For Small-Scale Horizontal Wind Turbines, Ayman I. Bakry, Mohamed Elfouly, Omar Mehrez

Journal of Engineering Research

Typically, small-scale wind turbines use either a breaking equipment or stall control methods once the wind speed exceeds its rated value. This is to limit the power extracted from the wind turbines which largely depends on the blades' shape and pitch angle. Most of small-scale wind turbines are of fixed pitch angle to avoid complexity and cost. In this work, a novel drive-rod unified variable pitch drive mechanism is proposed for blades pitch control for small-scale horizontal wind turbines. The mechanism is powered by a DC motor coupled with a lead screw which in turn is connected to the pitch …

Pd Controller Design For Automotive Magnetorheological Semi-Active Suspension System, Ayman I. Bakry, Emad M. S. El-Said, Ahmed Shehata Gad, Ahmed Abd Almoez, Omar Mehrez

Journal of Engineering Research

Recently, there is a tendency towards the utilization of magnetorheological (MR) dampers in electrical vehicles (EV) due to its adaptability of active control devices with lower requirement of large power sources compared to the active damping systems. This paper investigates the performance of the most used control technique for MR dampers used in EV, the PID controller, under different road conditions. In this investigation, the Dynamic-Damper-Motor System (ADM-EV) is used as the EV suspension system model. Meanwhile, modified Bouc-Wen model is used as the MR damper model. The design procedure for the optimum design of the system controller parameters is …

Rotating Burlap For Improved Solar Still Performance: An Experimental Investigation, Alsaied Khalil, Mohamed Abdelgaied, Amir Nasr

Journal of Engineering Research

This experimental study investigates the performance of a modified solar still that utilizes a rotating burlap cloth to enhance water evaporation and productivity. Conducted in Tanta, Egypt within a hot desert climate, the system was designed with a 31° angle to maximize solar energy absorption. A 12V DC motor was employed to maintain continuous rotation of the burlap, ensuring consistent contact with the water surface and promoting enhanced evaporation. The modified system achieved a peak water temperature of 89.4°C, resulting in a total water output of 1.547 liters per day, which translates to 4.56 liters per square meter per day—an …

Performance Optimization Of Bi2te3 Thermoelectric Generator System Under Low Operating Heat Fluxes, Abd El-Moneim A. Harb, Khairy Elsayed, Ahmed S.T. Osman, Ahmed Abdo

Journal of Engineering Research

It is essential to boost thermoelectric generator performance because recent studies have revealed lower efficiency. Its leg dimensions and the thickness of the copper strip could be changed to achieve this. With its innovative approach of establishing the P-N legs' optimal dimensions while considering all interactions at lower operational heat fluxes, the present research aims to be fruitful for common applications. A comprehensive TEG model was created, utilizing a single objective optimization method. Key performance parameters, including voltage, hot side temperature, output power, and conversion efficiency, were evaluated through simulations and compared to conventional TEG systems. The findings showed that …

Numerical Analysis To Evaluate The Performance Based On Bi2te3 And Sige Thermoelectric Module, Abd El-Moneim A. Harb, Khairy Elsayed, Ahmed S.T. Osman, Ahmed Abdo

Journal of Engineering Research

This paper presents a numerical analysis evaluating the performance of thermoelectric (TE) modules utilizing 𝐵𝑖2𝑇𝑒3 and SiGe materials under both constant heat flux and constant temperature difference conditions. A three-dimensional model of TEG was developed and simulated using ANSYS FLUENT 19-R2. The model's accuracy was validated against existing literature. The study investigated the influence of these materials on power output, conversion efficiency, voltage, and temperature distribution across various operating conditions. The results demonstrate a linear relationship between heat flux/temperature difference and voltage/power output for both materials. The findings provide valuable insights for optimizing high-performance TE modules operating under constant heat …

A Comparative Study Of Cleaning Methods Across Various Dust Types: Optimizing Cleaning Techniques For Dust-Affected Photovoltaic Panels, Ahmed Moustafa, Ahmed Tohami, Hamdy Hassan

Journal of Engineering Research

Solar energy is increasingly crucial for generating electricity and reducing reliance on fossil fuels. However, the efficiency of photovoltaic (PV) panels is substantially affected by dust accumulation. This research aims to enhance the performance and longevity of solar panels by evaluating various eco-friendly cleaning techniques for different dust types: Yellow Sand, Normal Dust, and Mud. The methods tested include low, medium, and high-water flow rates, medium flow rates with a wiper, compressed medium flow, and air blowing. Key performance metrics such as temperature, current, voltage, and power were measured before and after cleaning to assess effectiveness. The results demonstrate that …

Three-Rigid-Link Manipulator Robot Inverse Dynamic Model Using Ann Based On Pid Controller, M.A. El-Gohary, M.S. Elksas, A. E. Banna, S.G. Ahmad

Journal of Engineering Research

This work proposes an inverse dynamics model of a three-rigid -link manipulator robot employing a PID controller based on artificial neural networks. In order to attain precise position, neural network control algorithms are designed to handle nonlinear issues including robot manipulator control and uncertainty compensation. An artificial neural network with two layers that uses feedforward training is trained using the back propagation technique. By just fusing the ANN with other traditional control techniques, the suggested controller gives the network more information on the composition and dynamics of the system. The PID controller generates data that is used to train neural …

Towards A New Era Of Surgery Using Intelligent Robot, Ahmed Mahfouz, Hassan A. El Gamal, T. Awad, M.B. Badawi

Journal of Engineering Research

This research aims to overcome the difficulties of surgical tumor removal, especially in brain tumors that needs precision and time saving of the operations. The traditional surgical approach often is slow and targeting accurate manual cutting of the tumor, which is time-consuming and increase the risk to the patient. The error in cutting the deep layers of the tumor can occur, which increase the cost and dangerous for the patient.

To overcome these challenges, a proposed solution involves designing a robot that can quickly and accurately remove tumors by following their contours as it comes from the medical imaging data, …

Evaluation And Improvement Of A Solar Still With A Pyramidal Shape By Modifying Its Basin Design, Yaf El-Samadony, Ss Elsayed, Mohamed Abd Elnabi, Ahmed Abdo

Journal of Engineering Research

As global demand rises, freshwater shortage is a serious obstacle that calls for sustainable desalination methods. To increase desalination productivity, this paper looks at integrating photovoltaic (PV) panels with a novel pyramid solar still architecture. Two distinct configurations of pyramid solar still absorbers were created, assessed, and contrasted with a conventional pyramid solar still: configuration (1) had a square base pyramid measuring 900 cm2 and a height of 12.5 cm, while configuration (2) had a pyramid base pyramid of 2500 cm2 and a height of 21 cm. The different pyramid proportions, working concepts, and system components were explained. A thorough …

A Numerical Study On The Thermal Management Of Cylindrical Lithium-Ion Batteries By Immersion Cooling: Effect Of Coolant Distribution, Alhussein M. Abdel-Hafeez, Mohammed B. Effat, O. Hassan, N. Y. Abdel-Shafi

Journal of Engineering Research

Management of the temperature of lithium-ion batteries (LIBs) is critical for ensuring their safety and optimal performance. As the electric vehicle industry continues to evolve rapidly, the demand for efficient battery thermal management (BTM) technologies has grown. Among these, dielectric fluid immersion cooling (DFIC) has emerged as a particularly promising solution. In this study, we evaluate the impact of varying the coolant distribution on the performance of a cylindrical lithium-ion module comprising 20 cells. Coolant distribution was controlled by varying the number of coolant inlets from one to five, keeping the mass flow rate constant at 10 g/min. The performance …

Numerical Investigation Of Temperature Distribution Analysis For A Domestic Refrigerator With Different Duct Shapes, Faisal Elhabashy, A.A. Hawwash, Aly M.A. Soliman, Walid G. Alshaer

Journal of Engineering Research

The domestic refrigerator is one of the most home appliance used and the enhancement in its performance will has a significant effect on energy saving and environment. Preserving food at low and uniform temperatures is especially important to avoid Food spoilage and decreases the microorganisms. The aim of this study is to investigate numerically a different duct shapes to achieve an efficient cooling in the refrigerator and keep the temperature at the required range, using software called SIMULIA. The numerical model was developed to simulate the refrigeration system accurately, porous media and heat balance techniques were combined to the conservation …

A Non-Standard Finite Difference Approach For Optimizing The Thermal Behaviour Of Photovoltaic Panel With Hybrid Cooling Techniques, E.F. El-Gazar, A.A Hawwash, Hamdy Hassan, Shinsuke Mori, Ayman Refat Abd Elbar

Journal of Engineering Research

A finite difference model is developed to simulate the thermal behaviour of the PV system with an innovative cooling system. The proposed cooling system combines an aluminium heat spreader (AHS) with phase change material (PCM) placed at the backside of the solar panel. The new non-standard model is solved using MATLAB software and is validated with real experimental data collected under hot climate conditions. The new nonlocal model is found to be more effective in analyzing heat transfer processes throughout the entirety of the PV system compared to conventional PV models. Additionally, the new cooling PV system has been compared …

Finite Element Analysis Of Stress-Induced Phase Transformation In Sma Wire, Ali M. Mamdouh, Ali S. Helal, Yasser A F El - Samadony

Journal of Engineering Research

Shape memory alloys (SMAs) are well-known for their remarkable mechanical properties, particularly their shape memory and super-elasticity abilities. These Properties make them ideal for a variety of adaptive mechanical applications. The most common application is the implementation of SMA wires as mechanical actuators. However, the nonlinear characteristics and the hysteresis nature of SMAs limit their utility in engineering applications. This makes SMAs desirable, but it is considered a complicated material for developing advanced rehabilitation devices that can significantly enhance patient treatment. In this paper, a finite element analysis, (FEA) study investigated the behaviour of SMA wires under mechanical loads. COMSOL …

Design, Modeling, And Control Of Medical Service Quadrotor, Mohamed Eid, Anas Mohamed, Ali M. Mohamed

Journal of Engineering Research

Due to road accidents, it is difficult to supply injured people with first aid, especially in difficult-access regions. Also, uneven roads or far places pose a problem for ambulances and doctors to reach and save injured people’s lives. The paper aims to design, model, and control a drone able to fly at different heights and support patients with essential needs after accidents. The drone also contains sensors to measure blood sugar and pressure in cases of diabetic coma that require urgent intervention. The drone design was tested using SolidWorks and FLUENT to ensure safe design in different flying conditions. The …

A Review Of Performance Assessment Of Solar-Driven Absorption Chillers Incorporated With Energy Storage Systems, A. Khalil, Mohamed Abdelgaied, May Abdelsalam

Journal of Engineering Research

Abstract- This study evaluates the performance of a solar

collector absorption chiller combined with Phase Change Material (PCM) energy storage devices. Solar energy is used for energy-efficient cooling, and PCM storage improves

efficiency by capturing surplus thermal energy during

abundant solar radiation and releasing it when insufficient. The research assesses performance measures like

COP, energy storage capacity, and overall system efficiency.

Assessment Of Physical And Ergonomic Hazards And Their Compliance With National Standards. A Case Study, Amira Abdelraheem

Journal of Engineering Research

Occupational hazards are a significant concern in high-risk environments such as petroleum operating companies, where workers are exposed to various risks, including chemical, physical, mechanical, ergonomic, and psychosocial factors. Effective management of these hazards is essential to protect the health and safety of employees and maintain operational efficiency. This study aims to assess physical hazards including a-weighted equivalent noise levels, heat stress, Lightning and Ergonomics in a petroleum operating company in Egypt, and to check its conformity with national standards. Physical environment (Noise, heat stress and illumination) in different worksites were assessed using calibrated direct reading instruments to evaluate the …

Investigating The Structure-Property Correlations Of Pyrolyzed Phenolic Resin As A Function Of Degree Of Carbonization, Ivan Gallegos, Vikas Varshney, Josh Kemppainen, Gregory Odegard

Michigan Tech Publications

Carbon-carbon (C/C) composites are attractive materials for high-speed flights and terrestrial atmospheric reentry applications due to their insulating thermal properties, thermal resistance, and high strength-to-weight ratio. It is important to understand the evolving structure-property correlations in these materials during pyrolysis, but the extreme laboratory conditions required to produce C/C composites make it difficult to quantify the properties in situ. This work presents an atomistic modeling methodology to pyrolyze a crosslinked phenolic resin network and track the evolving thermomechanical properties of the skeletal matrix during simulated pyrolysis. First, the crosslinked resin is pyrolyzed and the resulting char yield and mass density …

A Structural Evaluation And Design Optimization Of A Tow Bar For Disabled Snowmobiles, David M. Pevic

Masters Theses

Snowmobile tow bars are devices used to rigidly connect two snowmobiles, such that a disabled snowmobile can be recovered from a remote location with a working snowmobile. These devices, however, are not widely used or readily available. An existing tow bar design was evaluated and redesigned to improve its structural capacity and performance. This evaluation provided a baseline to quantify improvement and included Finite Element Analysis (FEA), Design Failure Mode and Effect Analysis (DFMEA), and Design for Assembly analysis (DFA). A review of existing snowmobile tow bar patents was also performed. An updated design was then fabricated and similarly evaluated. …

Processing, Testing, Failure Analysis, And Modeling Of Elementary Natural Fiber-Reinforced Composites, Shuo Sun

All ETDs from UAB

Natural fiber reinforced composites have garnered significant interest as potential substitutes for conventional materials because of their eco-friendly attributes and favorable physical and mechanical properties. Typically, natural fibers undergo chemical treatments to enhance their compatibility with the polymer matrix prior to composite production. However, these treatments primarily affect the surface of the fiber bundles and have a limited impact on the inner elementary fibers within the bundle. This research work introduced a mechanical treatment method for hemp fiber by using an elevated temperature aqueous condition and mechanical force, which broke down the technical fiber bundles into elementary fibers and created …

Lessons In Low-Tech: A Handbook For Sustainable Education, Ceri Almrott, Loann Astorino, Sébastien Bette, Benoit Delinchant, Philippe Fortemps, Ulysse Girard, Paul Hendrick, Sacha Hodencq, Fabian Lecron, Julie Lhuissier, Kévin Loesle, Luis Miguel Lopez Santiago, Santiago Perez Rodriguez, Gauthier Renard, Tatiana Reyes, Virginie Vandenbulcke, John Walsh

Other resources

LT4SUSTAIN, an Erasmus+ funded transnational project, is at the forefront of responding to the increasing awareness of environmental and climate challenges. This awareness, particularly among youth, has led to a demand for social justice. With the coordinated work among six institutions, ranging from higher education institutions to private companies and associations, LT4SUSTAIN aims to raise awareness of Lowtech across society.

LT4SUSTAIN is pioneering a unique approach to technology design. By developing “hackathons” and other “hands-on” events, we are engaging students and industry in a way that improves inclusiveness. Our objective is to equip individuals with the skills to embark on …

Integrating Medical Plastic Waste Pyrolysis And Circular Economy For Environmental Sustainability, Attia Attia, Mohamed Bassyouni Prof., Reem Nasser Eng., Moataz El-Bagoury Eng., Islam Shaker Eng., Yasser Elhenawy Prof., Dina Aboelela Dr.

Biochemical Engineering

A critical assessment of pyrolysis technologies and reactor designs was discussed, highlighting various reactor configurations. This study explored the influence of catalysts, temperature, heating rate, and residence time on the pyrolysis process, and addressed their effects on product distribution and composition. Safety considerations and strategies for mitigating the potential environmental impacts of pyrolysis were presented. Comparative analyses of the environmental impacts of traditional waste disposal methods versus pyrolysis-based approaches provided insights into the potential reduction of greenhouse gas emissions and other pollutants. The circular economy approach was explored in the context of medical plastic waste pyrolysis. The potential for closing …

Feasibility Study Of A Smart Insole With Triboelectric Energy Harvesters For Early Flatfoot Detection, Mohammad Alghamaz

Mechanical Engineering Theses

This study introduces a self-powered smart insole system designed for real-time monitoring of foot health, with a specific focus on detecting flatfoot conditions. The insole integrates multiple triboelectric energy harvesters strategically positioned to capture electrical signals generated from ground reaction forces during daily activities such as walking, jogging, and running. Proof-of-concept testing was conducted on a single participant under two conditions: a healthy foot and a simulated flatfoot created by reducing the medial arch height by approximately 70\. In the healthy foot trials, the system demonstrated consistent and reliable performance, with negligible electrical output from the medial arch sensor, as …

A Computational Fluid Dynamics Approach To Analyze The Virtual Impactor In Pneumatic Aerosol Jet Printing, Akashita Sareen

Theses, Dissertations and Capstones

Aerosol jet printing (AJP) is a 3D printing, advanced manufacturing process that generates an aerosol mist appropriate for fine printing small, low-volume electronic parts. The pneumatic aerosol jet printing technology’s virtual impactor is the focus of this study. In this technology, high velocity nitrogen gas aerosolizes various inks in the atomizer. The aerosolized stream of ink is then transported to a virtual impactor (VI) to become dense and concentrated as it begins to enter the deposition head for high precision electronics printing. AJP faces challenges in large-scale adoption due to challenges related to overspray, instability, ink clogging etc. There is …

A Systems-Based Framework For Product Circularity Assessment, Gisele Bortolaz Guedes, Junwon Ko, Fazleena Badurdeen, I. S. Jawahir, K. C. Morris, Vincenzo Ferrero

Mechanical Engineering Faculty Publications

One of the key aspects of Circular Economy (CE), particularly when focusing on the product level, lies in its emphasis on designing products to facilitate the circulation of resources and maximize value throughout their entire lifecycle. To effectively develop such products an understanding of the characteristics of circular products (CP) is needed. Adopting a systems perspective that considers the total lifecycle and stakeholders involved and recognizing interdependencies among them is essential for identifying factors that characterize CPs. Existing methods for assessing product circularity do not identify all factors that charac- terize CPs and have limitations in the measurement methods proposed, …

Foundational Robotics, Akshit Lunia, Ananya Nagabhushana Rao, Yue Wang

Robotics

This textbook is a product of Co-DREAM OER (Collaborative Development of Robotics, Mechatronics, and Advanced Manufacturing Open Educational Resources), a US Department of Education-funded initiative to develop Open Educational Resource textbooks on robotics, mechatronics, and advanced manufacturing processes. It has been created by a diverse team of scholars and graduate students from across the country and is intended for higher-level robotics courses offered by 4-year undergraduate programs.

Multiobjective Optimal Design Of Hierarchical Control Architectures For Quadcopter Systems: Linear And Hybrid Approaches, Xinhuang Wu

Theses, Dissertations and Capstones

This thesis investigates the design of many-objective optimal controllers for quadcopter unmanned aerial vehicles (UAVs), focusing on both linear and hybrid control structures. In Chapter 2, a multi-input–multi-output (MIMO) optimal control system is developed for a six-degree-of-freedom UAV actuated by four brushless DC motors. The UAV dynamics are first derived and linearized around an operating point, and then organized into a three-loop nested control structure. The outer loop computes the roll and pitch angles required to maneuver the vehicle in the global X and Y directions, the middle loop regulates attitude and altitude, and the inner loop controls the angular …

Improving The Reliability Of Parts Produced Via Laser Powder Bed Fusion Through A Data-Driven Geometry Optimization Methodology, Federico Venturi

Mechanical and Aerospace Engineering Dissertations - Archive

This research aims to qualify the effect of design geometry on quality metrics of additively manufactured (AM) components that define reliability. Through the use of a novel methodology to characterize these quality metrics, AM components are inspected for the presence of defects such as surface roughness notches and porosity. These directly hinder the high-cycle fatigue characteristics demonstrated through the Kitagawa-Takahashi diagram and the El-Haddad model. By demonstrating the effect of geometry through a designed experiment and the adoption of the Murakami square root area parameter and Arola-Ramulu model, the improvement to fatigue life can be quantified. Incorporating this data into …

Stress Analysis Of Anisotropic Inclusion Problems Using Complex Variables, Liming Chen

Mechanical and Aerospace Engineering Dissertations - Archive

This research presents an analytical framework for determining stress fields in an elastic medium containing a circular anisotropic inclusion embedded in an infinitely extended isotropic matrix subjected to far-field uniform stresses. Stress distributions within both the inclusion and the matrix are described using classical stress functions, widely employed in two-dimensional elasticity theory.

To manage the complexity of the mathematical derivations, symbolic computation software (Mathematica) is used to streamline the analysis and obtain closed-form solutions. This approach overcomes traditional computational barriers that have limited the practical application of complex variable methods (CVM) in elasticity.

The methodology builds upon the foundational work …