DEPARTMENT OF THE MECHANICAL ENGINEERING

With the rising need to maximize passenger’s comfort, especially with the rising demand for selfdriving vehicles, alternatives to the popular passive suspension system have been on the rise. In order to improve the stability of a vehicle and reduce the vibration transferred to the passengers of the vehicle due to different road profiles, it has become necessary to implement a smarter type of suspension system that can respond to different type of road profiles and provide improved damping experience. This type of suspension system is the active suspension system. In order to analyze and simulate an active suspension system, parameters like the sprung and unsprung mass, spring and tire stiffness, damping constant of the damper were accounted for. Then the mathematical model of the system in the time domain was generated. Mathematical model was transformed from the time domain to frequency domain, using the Laplace transform. Then an appropriate controller for stabilizing the system was obtained. The simulated results show that the active suspension system performs better than the passive suspension in terms of settling time, rise time and overshoot and had lesser vibrations was transmitted to the passengers

This systematic review examines the effectiveness and feasibility of heating and ventilation systems as critical interventions to mitigate substantial post-harvest maize losses in Nigeria, which currently range from 20% to 30%. The core challenge stems from Nigeria's humid, tropical climate, where high temperatures and relative humidity foster pest infestations, microbial growth, and the dangerous production of aflatoxins by Aspergillus species. The study finds that uncontrolled heat, particularly in structures like metal silos, encourages harmful moisture migration and spoilage , while controlled heating remains a potential solution for active grain drying. Ventilation is identified as the key defense mechanism, but its implementation is complicated: traditional natural airflow systems often fail in the humid southern regions, and powered aeration faces significant constraints due to high ambient humidity and an unreliable electricity supply. The analysis concludes that a universal, one-size-fits-all approach to technology dissemination is inappropriate. Success depends on context-specific technology recommendations tailored to Nigeria's distinct agro-ecological zones, differentiated by production scale, and supported by complementary institutional capacity development. There is an urgent research and innovation gap in developing affordable, intelligent ventilation systems specifically designed for local climate zones. Furthermore, successful adoption relies on coupling technology promotion with market development strategies that enable farmers to realize economic premiums for improved grain quality.

This study presents the design, modeling, and simulation of a dual-shaft plastic shredder for recycling polyethylene terephthalate (PET), high-density polyethylene (HDPE), and low-density polyethylene (LDPE) waste. The research addresses the challenge of plastic pollution in Nigeria through a simulation-driven engineering approach that eliminates costly physical prototyping.
Using SolidWorks 2025 for computer-aided design (CAD) modeling and finite-element analysis (FEA), a comprehensive digital prototype was developed and validated. The shredder features two counter-rotating 50 mm diameter EN8 steel shafts with 32 AISI D2 tool steel blades, driven by a 2.2 kW three-phase motor operating at 120 rpm. Design specifications target a hroughput
capacity of 40–60 kg/hr with output flake sizes of 10–15 mm.
Validation was performed through three complementary methods: mesh convergence analysis confirmed solution independence with less than 4.2% variation in maximum stress; analytical validation using classical beam bending and torsion theory yielded results within 11.7% of FEA predictions (analytical: 132.3 MPa; FEA: 148.2 MPa); and mesh quality assessment confirmed
computational reliability with Jacobian ratios between 1.0 and 4.982. Simulation results demonstrate structural integrity with a maximum Von Mises stress of 148.2 MPa (33% of EN8 steel yield strength), negligible shaft deflection of 0.003 mm, and a minimum factor of safety of 3.2, exceeding the design requirement of 2.0 by 60%. The study successfully demonstrates that computer-aided simulation can produce reliable, optimized recycling machinery designs suitable for local fabrication, contributing to sustainable waste management solutions in developing economies.

Mooring systems remain one of the most critical safety components in marine operations, yet failures continue to occur across ports and offshore environments. These failures often lead to equipment damage, operational disruptions, and, in severe cases, loss of life. This study investigates the major causes of mooring system failures and evaluates the associated risks, with a particular focus on mooring practices in port environments. The research combines a detailed review of mooring system fundamentals with an assessment of human, environmental, and equipment-related factors that influence failure. A structured questionnaire was used to obtain first-hand information from marine professionals, and the responses were analyzed using the Failure Mode and Effects Analysis (FMEA) technique. The findings reveal that human error, inadequate inspection routines, worn mooring lines, and environmental forces such as strong winds and currents are leading contributors to mooring failures. Several failure modes were identified, but the highest Risk Priority Numbers (RPNs) were associated with poor maintenance culture, deviation from safety procedures, and the use of degraded lines. These areas represent the most urgent risks requiring intervention. The study also highlights gaps in compliance with standard mooring system management practices, including inconsistent adherence to the Mooring System Management Plan (MSMP). Based on the results, the research recommends stricter enforcement of mooring safety procedures, regular condition monitoring of mooring equipment, improved crew training, and the adoption of structured risk-assessment tools such as FMEA during operations. Strengthening these areas will significantly reduce the likelihood of failures and enhance the overall safety and reliability of mooring operations in Nigerian port environments.

This study investigates the technology employed in the production of Type 4 Liquefied Petroleum Gas (LPG) composite cylinders and explores potential improvements to enhance their performance, safety, and cost-effectiveness. Type 4 cylinders, composed of a polymer liner fully wrapped with fiber-reinforced composites, represent the most advanced generation of LPG storage vessels due to their lightweight structure, corrosion resistance, and superior burst strength. Data for the research were obtained through field observations at Don Mac Limited, review of standard operating procedures (SOPs), and engineering simulations. The study analyzed each stage of the production process—from liner molding and surface preparation to filament winding, curing, testing, and inspection—based on ISO 11119-3 and EN 12245 standards. Simulation results revealed that substituting high-density polyethylene (HDPE) liners with polyamide (PA11) and E-glass fibers with hybrid carbon–glass reinforcements increased burst pressure from 50 bar to 70 bar while maintaining a high factor of safety.

This project presents the design and fabrication of a system capable of reheating food and maintaining its temperature. Heat was generated by converting the electrical energy derived from both the Alternating Current (A.C) and Direct Current (D.C) source. The A.C circuit consisted of a heating element of 220V, 1kW power rating, and an electrical outlet a thermocouple and a temperature controller; the D.C circuit consisted of a mobile filament of 6V, 55W power rating, a dry cell D.C lead battery of 12V and 18Ah a thermocouple and temperature controller. A cup of water, meat pie, and a bowl of cooked rice was used to test the system’s performance and the set temperature was 60 degrees (ºC). At the end of the A.C experiment, it took the system approximately 7 minutes to reach the set temperature in the case of water, 7 minutes for the meat pie, and 6 minutes for the cooked rice. Due to heat transfer conditions, the food overheated; the water reached a maximum temperature of 83 degrees and the meat pie reached a maximum temperature of 81 degrees (ºC). The time taken for the food to reach the set temperature value after heating was approximately 45 minutes. At the end of the D.C experiment, it took the system approximately 22 minutes to reach the set temperature in the case of water, 20 minutes for the meat pie, and 21 minutes for the cooked rice. Due to heat transfer conditions, the temperature of the food increased further; the water reached a maximum temperature of 70 degrees, the meat pie reached a maximum temperature of 66 degrees (ºC), and the cooked rice reached a temperature of 68 degrees. The time taken for the food to reach the set temperature value after heating was approximately 23 minutes.

As global energy demands continue to rise, the search for alternative and sustainable energy sources has become a critical area of research. According to the International Energy Agency’s (IEA) New Policies Scenario, global electricity demand is projected to increase by approximately 80% between 2012 and 2040 (Elhalwagy et al., 2017). This growing demand, coupled with environmental concerns related to fossil fuel consumption, has driven significant interest in renewable and clean energy technologies. Among the various emerging energy solutions, piezoelectric energy harvesting has gained attention as a promising approach to generating electricity from everyday human activities, such as walking. Piezoelectricity refers to the ability of certain materials to generate an electrical charge when subjected to mechanical stress. This phenomenon is particularly useful for harvesting energy from human movement, specifically footsteps. Footstep power generation utilizes piezoelectric materials embedded in floors to convert kinetic energy into electrical energy. In high-footfall areas such as train stations, shopping malls, pedestrian walkways, and university campuses, the cumulative energy generated from footsteps can be significant (Elhalwagy et al., 2017). If effectively captured and stored, this energy could power small electronic devices, lighting systems, and digital displays—contributing to sustainable urban infrastructure.

Car park management in Nigeria is largely manual, inefficient, and insecure, often relying on handwritten tickets and rope-operated barriers. These methods, coupled with an unreliable power infrastructure, lead to significant congestion and safety risks. This project addresses these challenges through the design and fabrcation of a cost-effective, solar-powered, automated car park access control system. The system architecture is based on a Master/Slave configuration using two ESP32 microcontrollers that communicate via the ESP-NOW protocol. The Master ESP32 serves as the central "brain," handling RFID authentication and image capture via an ESP32 camera. Upon an access attempt, the system immediately captures the driver's image and validates the RFID tag against a local database stored on an SD card. This process creates a secure visual audit trail by logging all attempts (granted or denied) with a timestamp and the corresponding image. The Slave ESP32 manages the physical "muscle", controlling the barrier's geared motor and monitoring an ultrasonic sensor for vehicle safety

Marine pollution is an escalating issue, particularly in shipping operations, where factors such as oil spills, ballast water discharge, and plastic waste pose serious threats to marine ecosystems and global trade. This study seeks to assess the impact of marine pollution on both shipping operations and the marine environment, offering insights into its root causes, consequences, and potential solutions. This thesis describes the nature of marine pollution, its key sources and their effects which brings to light the escalating pollution problem and its consequences on marine biodiversity, fisheries, the economic viability of coastal communities and shipping operations. It highlights the regulatory measures such as Marine Pollution (MARPOL) and the Ballast Water Management Convention. The research methodology employs a descriptive survey design that gathers data from marine engineers, ship operators, port officials and environmental officers. These findings are used to propose solutions such as stricter enforcement of environmental regulations, adoption of sustainable fuels and enhanced waste management strategies. This research emphasizes the dire need for industry-wide cooperation to diminish pollution, balance economic interests with environmental sustainability, and ensure the long-term resilience of both shipping operations and marine environment.

Sustainability impact assessment is a tedious exercise to determine if a project is worthwhile by subjecting it to different methods of analysis. In this project, an assessment was conducted on utilizing synthesis gas as a substitute to conventional fossil fuels such as gasoline, for household power generation. The methods embarked on in the course of study included the Life Cycle Analysis, Techno- Economic Assessment, and Cost Benefit Analysis. Global warming potential (GWP) of utilizing syngas was checked for and it was seen that it was gotten to be 0.111kg CO2 equivalent and its acidification potential is 4.4E-4kg SO2 equivalent and human toxicity potential is 8.86E-2kg, 1-4 DB equivalent. It showed promise of being an eco-friendly method of power generation. In regards to the economic assessment, it was found that the Levelized Cost of Electricity was ₦34.009/kWh and this is seen definitely as a cheaper option than that offered by the current distribution rate seen in the country. The NPV as at the end of 20 years was seen to be - ₦157,606.95. Methods of reducing this and making it a positive value was also explored. This included reducing the cost of Operation and Maintenance by 30% and the Biomass cost by 40%. In summary, synthesis gas has a very exciting future in the process of power generation. The findings offer scientific proof for the design and deployment of the hybrid technology to improve energy security, while reducing carbon emissions. Overall, this study brings to light the potential benefits of biomass energy systems and encourages the implementation of sustainable practices regarding energy for a greener future.