DEPARTMENT OF MECHANICAL ENGINEERING

This study investigates the impact of Nigeria’s tropical environment on the performance of marine diesel engines, focusing on how climatic factors such as air temperature, humidity, atmospheric pressure, and seawater temperature influence engine efficiency Nigeria’s coastal regions are characterized by consistently high temperatures, intense humidity, and seasonal rainfall variations all of which can affect combustion efficiency, cooling capacity, and fuel consumption in marine engines. In this study, an analysis was conducted on the thermodynamic effects of ambient air temperature, humidity, pressure, and seawater temperature on marine diesel engine performance. A simulation framework integrating ISO correction principles with OEM performance curves was developed and applied to model daily and seasonal variations in Nigeria’s tropical environment using meteorological data. The simulated results were validated against manufacturer reference conditions, and based on the findings, technical, operational, and maintenance strategies were proposed to enhance marine diesel engine
efficiency under tropical conditions. Overall, the analysis showed that Nigeria’s tropical climate caused a minor but consistent derating of marine diesel engine performance. Air temperatures between 32–34 °C and humidity above 75 % led to about a 2–3 % reduction in power and a 0.1–0.2 % increase in specific fuel oil consumption compared to ISO conditions. High ambient heat and warm seawater (around 30 °C) reduced air density and charge-air cooling efficiency, resulting in slightly higher fuel flow rates. Despite these effects, the Wärtsilä 8L32 demonstrated stable exhaust temperatures and strong load control, indicating good adaptability to tropical conditions.

The problem of electricity in Nigeria has become some sort of a nationwide pandemic that has plagued the country for years and continues to do so. With seemingly no end in sight to the electricity crisis, food storage has become very expensive as individuals as well as producers, need to pay a lot of money to run generators to power refrigerators. An alternative means to this would
be a more than welcome development. This project aims to reduce the cost encountered in refrigeration by using vapor absorption refrigeration, which is powered by solar energy.
The vapor absorption refrigerator uses water as its refrigerant, and zeolite is used as the absorbent. The compression system is a network of systems consisting of an absorber and a generator, aimed at compressing a liquid refrigerant-absorbent mixture that requires less work to compress than vapor. The temperature of the evaporator, generator, and condenser was measured and recorded periodically. The performance of the system is evaluated as the ratio of heat removed from the refrigerated space to the heat added to the system at the generator. The refrigerator proved quite functional, achieving a COP of 0.66. This validates the functionality of the system, but it was observed that it took 3 hours of heating to produce a 9°c drop (from 34.2°c to 25.2°c) in evaporator temperature. After 5 hours of heating, there was a 15°c drop (from 34.2°c to 19.2°c) in evaporator temperature. However, the atmospheric temperature was 27°c which means the cooling achieved was not appreciable. The system used in this project suffered from a lot of leakages and heat loss, which directly affected the performance of the system. We recommend
that further studies on techniques that would prevent heat loss, and a meticulous fabrication process to prevent leakages allow. Significant reduction in heat loss would greatly improve the
performance of the waste solar-powered VARS, thereby making it more viable and suitable for domestic and commercial usage

The conventional mechanical governor, while robust, suffers from limitations in dynamic response and optimal performance under varying operational conditions. This project presents the design and implementation of a Smart Mechanical Governor that leverages Machine Learning (ML) for automated, real-time performance tuning. By integrating sensors to monitor key operational parameters (such as speed, load, and fuel flow) and an actuation mechanism for adjustment, the system creates a closed-loop feedback environment. Supervised learning algorithms are trained on historical performance data to model thecomplex, non-linear relationship between governor settings and system output. This ML model subsequently predicts the optimal calibration settings to achieve target performance metrics, such as enhanced stability, reduced settling time, and improved fuel efficiency. The proposed system aims to overcome the static nature of traditional governors, enabling self-optimization that adapts to engine wear and changing environments. The results demonstrate that the ML-driven approach significantly outperforms static calibration, offering a transformative upgrade for internal combustion engines in automotive, aerospace, and industrial power generation applications.

This project presents the design and construction of a Gesture Control Smart Lighting System aimed at enhancing accessibility and improving energy efficiency in residential and commercial
environments. Traditional lighting systems rely on manual switches, which may present challenges for elderly individuals, persons with disabilities, or in situations where physical contact
is inconvenient. The proposed system utilizes gesture recognition technology to enable users to control lighting functions such as switching ON/OFF and adjusting brightness through simple
hand movements without physical contact. The system integrates a microcontroller-based platform with gesture sensors to detect and interpret predefined hand motions. These gestures are processed and translated into lighting control commands in real time. The design prioritizes low power consumption, reliability, affordability, and ease of installation. By eliminating unnecessary energy usage through automated control and user-friendly interaction, the system contributes to energy conservation and promotes sustainable living.
Experimental testing demonstrates that the system responds accurately to gesture inputs with minimal delay, ensuring efficient performance and improved user convenience. The developed
prototype highlights the potential of gesture-based smart systems in advancing modern home automation, particularly for enhanced accessibility and energy-efficient lighting solutions.

The increasing global demand for clean and sustainable energy has intensified the need for innovative solutions that harness renewable resources. This project explores the design and implementation of hybrid electricity generation system that integrates wind turbines and solar photovoltaic (PV) panels. By combining these two complementary energy sources gives an efficient means of power generation, particularly in regions with variable weather conditions. The wind turbine component captures kinetic energy from wind currents, while the solar panels convert sunlight into electrical energy. Together, they form a synergistic system capable of reducing dependence on fossil fuels, minimizing environmental impact, and enhancing energy security. The project also examines key technical aspects such as system configuration, energy storage, power conversion, and grid integration. Through simulation and analysis, the study demonstrates the feasibility and benefits of hybrid renewable energy system in meeting electricity demands sustainably.

Carbon steel is fundamentally an alloy comprising of iron and carbon, and other alloying elements such as manganese with 1.0% maximum content and silicon with 0.3% maximum content (Onyekpe, 2002). It is the most important steel used in petroleum and chemical industries since it accounts for over 98% of the construction materials. Carbon steels materials are predominantly used for flow lines, transmission pipelines and downhole tubulars in the oil and gas industry, most possibly owing to their low cost (Nesic et al, 2010; Ghareba et al, 2010; Liu et al, 2011; Badr, 2009). For instance, the cost of stainless steels especially that of austenitic steels (AISI 304 & 316) is currently about 8 times greater than that of carbon steels (Panossian et al, 2012; Finsgar et al, 2014). Among the most widely used carbon steel is the medium carbon steel. It is classified on the basis of their carbon content varying from 0.25% to 0.5%. The carbon steel that has been mostly used as the main production material for transmission pipelines, downhole tubulars, and flow lines in the oil and gas industry is API N80 (Walker, 1994; Yadav et al, 2012; Vishwanatham et al, 2008; Zhu et al, 2011), with carbon varying from 0.23% - 0.52%, (Finsgar et al, 2014). However, this material is susceptible to corrosion when used in chloride environment without any form of surface treatment or protection (Seidu and Ketulu, 2013).

Nigeria’s energy security is heavily reliant on natural gas, a strategy hampered by supply unpredictability and growing global decarbonisation requirements. To address frequent outages caused by gas supply constraints and CO₂ emissions of 350-400 kg/MWh, a strategic pivot is necessary. This study proposes a transformative approach to addressing these dual challenges by retrofitting the Afam VI Natural Gas Combined Cycle (NGCC) power plant into an innovative Integrated Gasification Combined Cycle (IGCC) system. The study looks into the techno-environmental feasibility of repurposing existing infrastructure to use domestic coal and biomass blends, hence increasing fuel flexibility and lowering the plant’s carbon footprint.
This work applies a rigorous simulation-based technique using EBSILON® Professional. A validated baseline model of the present Afam VI plant, which operates at 49.88% efficiency at base load, was created. This model was later updated to incorporate a gasification unit, air separation unit, syngas clean-up techniques and pre-combustion carbon capture. Necessary modifications were also made to the topping and bottoming cycle of the thermal block for syngas combustion. Thermal analysis was carried out to assess system performance under both design and off-design scenarios. The results shows that the IGCC retrofit model reduces the net plant emission of the natural gas baseline model from about 300kg/MWh to about 50kg/MWh, indicating an 85.7% reduction in CO2 emission with a potential for carbon neutrality using biomass as feedstock. However, this comes off on the back of a trade off with the thermal performance of the plant. The retrofit model was found to have an energy efficiency penalty of about 4% points with respect to the natural gas baseline. This results suggests that retrofit IGCC technology is not only technically feasible, but also strategically important for decarbonising the energy industry. It offers a practical, data-driven strategy for using indigenous energy resources to create a more resilient, sustainable, and secure power system. By presenting a feasible model for deep decarbonisation of existing infrastructure, this effort combines national development aspirations with global climate action, establishing IGCC as a baseline for future flexible and clean power generation.

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.

This report details the design and implementation of an electric-solar vehicle, focusing on the fabrication and testing of its inverter. The inverter, a crucial component for efficient power conversion, was developed to optimize the integration of solar energy with an electric motor drive. This report focuses on the practical aspects of the inverter's construction and performance evaluation.
The design considerations are outlined, followed by a detailed description of the component selection, PCB fabrication, and assembly. Performance testing results, demonstrating the inverter's efficiency and suitability for the vehicle, are also included.

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 analysed 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 onitoring 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.