DEPARTMENT OF THE MECHANICAL ENGINEERING

The growing concern over ineffective waste management in rapidly urbanizing areas has continued to threaten environmental sustainability, public health, and urban aesthetics— particularly in developing nations such as Nigeria. Conventional waste collection methods, which rely on manual inspections, static collection schedules, and minimal automation, are increasingly inadequate for modern cities. These traditional systems often result in overflowing waste bins, unhygienic surroundings, and increased exposure of sanitation workers to hazardous waste. To mitigate these challenges, the adoption of smart waste management systems has become a practical solution, harnessing Internet of Things (IoT) technologies to enhance operational efficiency, reduce health risks, and support global sustainability goals. This project presents the design and development of an improved smart dustbin system, which integrates sensors, automation, and wireless communication for efficient and hygienic waste collection. The system was engineered to address major limitations of existing smart waste bin models—such as lack of automation, low adaptability to environmental conditions, and poor sustainability—by introducing enhanced features that improve functionality, reliability, and user safety. The prototype incorporates ultrasonic sensors for detecting the fill level and load cell sensors for measuring the weight of accumulated waste. These sensors interface with an Arduino microcontroller, which interprets real-time data and initiates corresponding control actions. A key innovation in this design is the dual alert and communication mechanism, facilitated by a GSM module (SIM900D) that transmits SMS notifications and also initiates automated phone calls to designated waste management personnel once the bin reaches its full capacity. In addition, the system integrates a GPS module that tracks the exact location of the bin, simplifying collection logistics and enabling efficient route planning. To further enhance automation, the system features a linear actuator that performs self-compaction, reducing the waste volume and increasing the storage capacity before the next collection. Importantly, once the waste bin reaches its maximum threshold, the lid is automatically locked, preventing further deposit of waste and ensuring cleanliness until the bin is emptied and reset for operation. This mechanism helps prevent overflow and reduces contact with potentially contaminated waste. The system is powered by a 24W rechargeable lithium battery supported by a DC–DC converter, ensuring stable power supply and efficient energy usage. The software component was developed using Embedded C/C++ on the Arduino IDE, enabling real-time sensor monitoring, threshold detection, and GSM/GPS communication control. Comprehensive testing was carried out to evaluate sensor accuracy, power efficiency, communication reliability, and the responsiveness of the compaction and locking mechanisms. Results from both hardware and software testing confirmed that the system achieved reliable waste level detection, efficient data transmission, timely alert notifications, and effective compaction cycles. The automatic locking feature also performed accurately, preventing waste input once the bin reached capacity. By combining IoT technology, automation, and sustainable material selection, the improved smart dustbin system demonstrates a viable, scalable, and eco-friendly approach to modern waste management. Its ability to autonomously monitor fill levels, compress waste, lock when full, and communicate through both SMS and phone calls significantly enhances efficiency, hygiene, and sustainability. This prototype provides a foundation for large-scale implementation in residential, institutional, commercial, and municipal environments, contributing to cleaner cities and smarter waste management systems that align with sustainable development goals.

This study presented a comprehensive investigation into the failure mechanism and performance modelling of the combustion and emission characteristics of an industrial dualfired steam boiler operating on natural gas and diesel. The study was driven by the reoccurring failure on the third pass, operational inefficiencies and concerns over the environmental performance observed in the boiler system of a bottling company in Nigeria The failure investigation component of the study involved a systematic diagnostic assessment of the third-pass tubes including visual inspection, chemical composition analysis, micro- structural analysis and water chemistry analysis. For performance evaluation, the study employed experimental measurements and computational fluid dynamics (CFD) simulations using ANSYS Fluent to model combustion dynamics, temperature distribution, pollutant formation, and flue gas flow behaviour under various operating loads and fuel combinations. The models were validated against plant data, Furthermore, parametric studies were conducted to optimize key operational boiler control parameters such as air flow, load, variable frequency drive (VFD) and fuel flow rate using Taguchi methodology. Failure investigation results revealed key degradation phenomena due to due to thermal stresses, corrosive water chemistry, tube fouling, scaling, fouling-induced heat transfer impairment. Also, micro-structural examination showed thermal degradation, including decarburization, grain growth, and oxidation, alongside pitting corrosion, indicating high-temperature exposure and scale deposition weakened the metal. The water chemistry analysis revealed elevated levels of total dissolved solids, P-alkalinity, chloride, and silica in the boiler drum water, which contribute to scaling and localized overheating. Major failures was traced to inadequate water treatment and poor combustion control. CFD simulations revealed that scale layers significantly reduces heat transfer, leading to increased failure risk. An optimal water mass flow rate of 0.454kg/s was determined as the effective mass flow rate to attain the desired outlet steam temperature. The study revealed load as the most influential factor, leading to reduced emissions, improved combustion, operational stability and prolonged component life. The findings provide insights into enhancing boiler reliability, thermal efficiency, and environmental compliance.

The rising global demand for sustainable and renewable energy sources has intensified interest in biofuels as viable alternatives to fossil fuels. This study focuses on the synthesis and characterization of biofuels derived from selected Nigerian crops, with the aim of exploring their potential as eco-friendly energy resources. Locally available feedstocks such as palm oil, groundnut oil, and cassava were utilized for biofuel production through transesterification and fermentation processes. Physicochemical properties of the synthesized biofuels—including density, viscosity, flash point, calorific value, and cetane number—were analyzed in accordance with ASTM standards and compared with conventional diesel fuel. The results revealed that the produced biofuels exhibited properties comparable to standard diesel, indicating good ignition quality and combustion efficiency. Variations in yield and performance were attributed to differences in the oil content and fatty acid composition of the feedstocks. Furthermore, the study established that Nigerian crops provide a sustainable raw material base for biofuel production, with minimal environmental impact and strong potential for rural economic development. The research concludes that biofuels synthesized from indigenous Nigerian crops are promising renewable energy alternatives capable of reducing dependency on petroleum-based fuels and mitigating carbon emissions. The study recommends further optimization of production parameters and scaling up of local biofuel technologies to enhance energy security and environmental sustainability in Nigeria.

Heat exchangers are fundamental components in thermal engineering, enabling efficient transfer of heat between fluids across various phase states. Their performance largely depends on the thermal characteristics of the working fluid, and improving these characteristics remains a central research focus. Nanofluids—base fluids enhanced with suspended nanoparticles—have emerged as promising candidates due to their potential to significantly improve heat transfer rates. This study investigates the viability of nanofluids as enhanced working fluids for heat exchanger applications, addressing the persistent challenge of increasing heat transfer efficiency in thermal systems. The methodology involved selecting a shell-and-tube heat exchanger and performing detailed mathematical modelling, numerical simulations, and comparative analyses. Simulations were conducted using ANSYS Fluent, supported by theoretical models such as the Maxwell-Garnett relations, Pak and Cho density formulation, and Brinkman viscosity correlations. Mesh generation, boundary condition setup, and performance evaluation were carried out systematically between July and November 2025. Various nanofluid types and volume fractions were iteratively tested to identify the most thermally efficient fluid configuration for the system. The results demonstrate a clear improvement in heat transfer characteristics when nanofluids are employed compared to conventional fluids. Significant enhancements were observed in thermal conductivity, convective heat transfer coefficients, and reduction in hot-air exit temperatures from the heat exchanger. The comparative outcomes confirm the strong potential of nanofluids to boost thermal energy recovery and overall system performance, highlighting their suitability for advanced industrial heat exchanger applications.

This project focuses on the reverse engineering, adaptation, and performance evaluation of a 1-horsepower (HP) air-source heat pump tailored for Nigeria's unique climatic and infrastructural challenges. Rising temperatures, erratic power supply, and high humidity levels in Nigeria have intensified the demand for energy-efficient and resilient cooling solutions. This study addresses this need by deconstructing a commercially available 1 HP unit, analysing its core components—including the compressor, condenser, evaporator, and capillary tube—and modifying them for optimal performance within the local context. The methodology involved an iterative design process, selecting and adapting components to withstand high ambient temperatures (up to 45°C), significant humidity fluctuations (20-95%), and unstable grid voltage. Key modifications included increasing the condenser surface area by 15% for better heat rejection, integrating a voltage stabilizer, and employing a capillary tube as a cost-effective, bidirectional expansion device suitable for reversible operation. The fabricated system was rigorously tested in a controlled environment, demonstrating a stable cooling capacity. Performance analysis revealed a Coefficient of Performance (COP) of 3.45 in cooling mode and 4.11 in heating mode, confirming the system's high energy efficiency and dual-functionality. The project successfully achieved its primary objectives of component analysis, demonstration of dual-mode operation, and energy efficiency evaluation. It also fulfilled secondary goals, including refrigerant cycle analysis and the design of a modular control system. The results validate the technical and economic viability of locally reverse-engineered heat pumps, which can reduce reliance on inefficient conventional air conditioners, lower electricity consumption, and decrease greenhouse gas emissions. This work provides a foundational framework for the local manufacturing and adoption of sustainable thermal comfort technology in Nigeria, contributing to energy security, climate adaptation, and technological self-reliance. Recommendations are provided for further performance enhancements, including the adoption of inverter compressors, transition to low-GWP refrigerants, and optimization of heat exchanger design.

The study focused on redesigning an existing institutional waste receptacle that suffered from frequent misuse, excessive mass, cramped capacity, and overflow among other issues. Field observations revealed that ambiguous aesthetics prompted users to treat the unit as furniture or storage, while manual handling fostered surface contamination. The revised unit incorporates proximitytriggered lid actuation through combined infrared sensing and microcontroller logic, eliminating direct contact. Structural refinements replaced dense wooden elements with high-density polyethylene and thin aluminium composites, yielding a 52 % mass reduction and a 30 % smaller base area while increasing internal volume fivefold. Fabrication involved iterative prototyping, sensor calibration, and load-bearing trials. Controlled assessments demonstrated 94 % actuation consistency, zero observed lid contacts during disposal, and full elimination of prior misuse patterns. The resulting device presents a practical, low-maintenance intervention for hygiene-sensitive environments such as lecture theatres and administrative corridors.

The increasing incidence of theft and mismanagement of personal belongings in school libraries has underscored the need for a reliable and secure storage solution. This project presents the design and implementation of an RFID-Based Secure Storage System developed specifically for the John Harris Library, University of Benin. The system leverages Radio Frequency Identification (RFID) technology to provide an automated, user-friendly, and efficient means of storing and retrieving students’ personal items while ensuring security and accountability. A combination of hardware and software design methodologies was adopted. The development process involved three major stages: a user perception survey, system simulation, and physical implementation. The user survey established the need for improved storage security and confirmed students’ willingness to adopt an RFID-driven solution. The simulation phase, conducted using Proteus ISIS Professional, validated the system’s logic, data flow, and component integration before hardware assembly. The physical prototype was implemented using an ESP32 microcontroller, RC522 RFID reader, servo-based locker mechanism, and a dual power system supported by a Battery Management System (BMS) for stable operation under varying power conditions. Testing results revealed an average system response time of approximately two seconds and 100% tag recognition accuracy, confirming both reliability and efficiency. The dual power design eliminated voltage interference between the control unit and servo motors, while the BMS ensured safe and continuous functionality during power fluctuations. The system’s performance was evaluated using theoretical frameworks such as the Technology Acceptance Model (TAM), Security Theory, and Socio-Technical Systems Theory, all of which validated its usability, security, and integration of human and technical subsystems. The developed RFID-Based Secure Storage System successfully met its objectives of providing an automated, secure, and scalable storage solution for school libraries. It demonstrates how mechatronic engineering principles and RFID technology can be effectively combined to enhance campus security infrastructure, improve operational efficiency, and promote user trust in academic environments.

The development of affordable and efficient vacuum cleaners has become a significant concern for households and small-scale cleaning businesses, especially in developing regions where high-end vacuum cleaners are often too expensive. Vacuum cleaners are essential tools in maintaining clean indoor environments by removing dirt, dust, and other debris from floors and surfaces. However, the design and functionality of many low-cost vacuum cleaners are often compromised, especially in terms of air velocity, particle retention, and the efficiency of dust separation. These issues can lead to ineffective cleaning and the release of fine dust particles into the environment, undermining the overall effectiveness of the vacuum cleaner. Previous designs of vacuum cleaners fabricated from locally available materials often suffer from limitations such as inadequate air velocity through the wand, improper filtration of fine particles, and ineffective dust deposition mechanisms. These flaws not only reduce the cleaning efficiency but also compromise air quality in the environment. This study aims to review and improve upon the design and fabrication of such vacuum cleaners, addressing these critical issues to enhance performance and dust control.

Coconut is a cash and food crop that has the abaility to be grown even in bad weather, hence can be cultivated around all weathers and in virtually any geographical location in Nigeria. However; there are growing concerns of its judicious and profitable cultivation and post-harvest processing despite its commercial value as it can be consumed as food and its constituent parts can be used in pharmaceuticals, beverages, energy and power and a host of other products such as brooms, mats, floor mats. Prior to its use the coconut fruit is dehusked to remove its outer fiber shell. The dehusking process which conventionally involves the use of human effort using a sharp object is characterized by low output, susceptibility to injury and unhygienic nature. To mitigate these setbacks, a coconut dehusking machine was designed and fabricated using the design Methodology of reverse engineering. The machine had some components which include hopper, twin shafts with dehusking spikes, pulleys and pulley belts, bearings and a structural rame. Test and operational performance carried out on the machine showed that it was quite effective for dehusking various sizes of coconuts with a throughput capacity of 33 coconuts per hour. The efficiency of the machine was estimated as 83.3%. Effectiveness of the dehusking process was dependent on the dehusking force of the machine and the moisture content of the coconut fiber. A major advantage and achievement in this prototype was that more than one coconut could be dehusked simultaneously and the dehusked coconuts can be discharged automatically without the input of human effort.

To understand the popularity of electric vehicles circa 1900, it is also important to understand the development of the personal vehicle and the other options available. At the turn of the 20th century, the horse was still the primary mode of transportation. Steam emerged as a reliable energy source with a proven track record, notably powering factories and locomotives. In the late 1700s, steam also played a role in some of the earliest self-propelled vehicles. However, despite its early adoption in various applications, it wasn't until the 1870s that steam technology began to gain traction in the automotive industry. One significant reason for the delayed adoption of steam technology in cars was its impracticality for personal vehicles. Steam-powered vehicles faced several challenges that hindered their widespread use. For instance, they required considerable startup times, often up to 45 minutes, particularly in cold conditions. Additionally, steam vehicles needed frequent refilling with water, which imposed limitations on their range and practicality for everyday use. These drawbacks underscored the challenges associated with steam-powered cars and contributed to their eventual decline in favor of alternative propulsion methods, such as internal combustion engines and electric motors, which offered greater convenience and efficiency for personal transportation. As electric vehicles came onto the market, so did a new type of vehicle, the gasoline-powered car thanks to improvements to the internal combustion engine in the 1800s. Although gasolinepowered vehicles had potential, they were not without problems. They took a lot of human labor to operate because shifting gears was a difficult operation, and starting them required turning a hand crank, which some drivers found challenging. Gasoline-powered vehicles were also notorious for their noisy engines and nasty exhaust. (TOTAL ENERGIES, 2020) In contrast, electric cars did not suffer from the issues associated with steam or gasoline vehicles. They were quiet, easy to drive, and did not emit the noxious pollutants characteristic of other cars of the time. Consequently, electric cars rapidly gained popularity among urban residents, particularly women. They proved ideal for short journeys within the city, especially considering the poor road conditions outside urban areas, which limited the travel range of all types of vehicles. (Nilesh Wani, 2020)