Arid Zone Journal of Engineering, Technology and Environment (AZOJETE)
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Performance Analysis of Horizontal Axis Wind Turbine using Variable Blade Pitch Control Mechanism
Get PDFThis work investigates the performance of a horizontal axis wind turbine (HAWT) with variable blade pitch control mechanism. The control mechanism is a simple mechanical Watt governor design, which was developed to regulate the blade pitch angle of the HAWT depending on wind speed magnitude. The HAWT model with the control mechanism was tested for performance in a wind tunnel. Response of the control mechanism in terms of blade pitch angle, rotor speed and generator power output were analyzed based on regulated predetermined wind speeds. The result shows a gradual increase in rotor speed and a proportional increase in generator power output between cut-in wind speed of 2.5m/s and rated wind speed of 6 m/s. These parameters were kept constant at 100 RPM and 50 Watts as observed due to the steady response of the control mechanism. The steadiness lasted up to a cut-out wind speed of 9 m/s. The control mechanism subsequently shutdown the turbine at the cut-out wind speed to protect the turbine against wind speeds higher than 9 m/s. The performance test predicts that the variable blade pitch control mechanism was able to regulate and bring about the require control of HAWT model. The mechanism allows the turbine to only operate between 2.5 and 9 m/s at blade pitch angle between 82 and 90 degrees from the axis of wind flow and change in governor height between 0 to 8 mm
Evaluation of the Accessibility of Public Transport Facilities by Physically Challenged Commuters in Ilorin Town, Nigeria
Get PDFFollowing the persistent outcry of disabled persons over non accessibility to public transport facilities in Ilorin town, Nigeria, this study examined the plight of physically challenged commuters in accessing public transport facilities in the town. Questionnaires were administered to 201 disabled commuters who use public transport facilities in the study area. Facility condition inspection was also used to evaluate accessibility and user satisfaction. Results of the study revealed that; male disabled persons travelled at relatively high rate of 76.10% compared to the female folks at 23.90%. The common disability among disabled persons was physical disability at the rate of 77.10%, while visual disability was 22.90%. Travel demand among disabled persons showed that teenagers and adults travelled at relatively higher rate of 10.00% and 84.00% respectively compared to the aged at 6.00%. Begging and work trip purposes had relatively high rate of 29.35% and 21.38% respectively compared to other trip purposes. The commonest nature of disability among commuters included; wheelchair user, sight impairment and hearing difficulty at 25.40%, 22.90% and 18.90% respectively. Uneducated and disabled persons with primary education rated high in the sampled population at 36.80% and 29.90% respectively. Accessibility rating and physical inspection revealed the poor state of public transport facilities in Ilorin town leading to human right infringement, social exclusion and inequality among city dwellers. Therefore, right to travel and access to basic facilities as stipulated in the Nigerians Disability Decree of 1993 to enhance livability and ensure equality among city dwellers were ignored. The construction of public transport facilities to bear sidewalks, ramps, traffic control devices, bus stop shelter and good drainage systems to conform to international best practices in Ilorin town was recommended
Modelling of Heat Transfer Through Hollow Blocks Produced with Rice-Husk-Ash Blended Cement.
Get PDFHollow sandcrete blocks are widely used in many countries of the world. In recent years, cement content is being partially substituted by admixtures especially agricultural wastes. Modeling of heat transfer characteristics of these modified blocks is essential in order to predict their thermal performance. This study focuses on this modeling with the aid of a finite-volume based computer code. Specifically, for regular, two-cavity blocks produced with the cement partially substituted with rice husk ash (RHA). The result showed that as the percentage substitution of RHA increased, thermal gradient across the width of the block increased, while the rate of heat flow reduced. The second part of the study examined the effect of heat transfer through the air-gap as compared to a similar study regarding it as vacuum. The heat flow through the air-gaps of the building bricks affected the pattern of heat flow within the bricks, hence, they could not be regarded as a vacuum. The results of this study will be useful to building professionals in the choice of building blocks and proper estimation of air- conditioning load in buildings
Performance Evaluation of a Melon Seeds Shelling and Separation Machine
Get PDFThe scarcity of information on the performance of most machines developed in Nigeria impedes the commercialization of proven indigenous technologies. A newly developed melon seeds shelling and separation machine with the capability to continuously shell conditioned melon seeds and simultaneously separate the seed cotyledons from it shells was evaluated. The machine extracts heat exclusively from the exhaust gases of a gasoline prime mover by heat conduction principle, mildly dry the shelled melon seed mixture before effecting separation of the cotyledons from it shells by aerodynamic and screening principles. Based on preliminary studies, performance evaluation of the machine was carried out at 900, 1500 and 2100 rpm operating speed and 14, 20 and 26% db moisture content of white edge (Serewe) melon seed variety. The data obtained were analyzed using IBM SPSS statistic software version 25. Results of Analysis of Variance (ANOVA) at P ≤ 0.05 showed that, shelling efficiency and machine capacity varies significantly with the operating speed, moisture content of the seeds, and their interactions; while separation efficiency and seed breakage percentage varies significantly with the operating speed and moisture content of the seeds but not significant with their interactions. An optimal performance of 96% shelling efficiency, 95% separation efficiency, 2.67% seed breakage percentage and 54.23 kg/h machine capacity, was obtained at 2100 rpm operating speed and 20% db seed moisture level. The performance of the machine is satisfactory and therefore recommended for commercialization and adoption by melon seed processors
Development and Performance Evaluation of a Manually Operated Groundnut Roaster
Get PDFA manually operated groundnut roaster was developed and evaluated. The present Institute for Agricultural Research, Zaria (IAR) roasting equipment consists of a frying pan and an IAR charcoal fire wood cooking stove. The roaster was designed to help local processors obtain uniformly roasted products, with acceptable roast color. The performance of the roaster was carried out using IAR groundnut species known as SAMNUT 11 as specimen. The roaster was found to have a roasting capacity of 0.92 kg/min which is above the (IAR) roaster that has a roasting capacity of 0.28 kg/min. The roaster was found to have efficiencies of 98.3%, 98.6%, and 98.9% at 25%, 50% 100% loadings, respectively. The parameters that affect the roasting capacity include: heat from charcoal, crop moisture content and crop variety
Performance Evaluation of Solar Oven Using Kapok Wool as Insulation Material
Get PDFSolar ovens are among common devices which utilize insulation materials because of their ability to retards heat transfer by acting as barriers in the path of heat flow. Previous solar box cookers have used cotton, saw dust, and fibre-glass as insulation materials but none has used Kapok wool despite its potential. This study is aimed at the performance evaluation of solar oven using Kapok wool as the insulation material. The solar box oven designed is of the size 59 x 56 x 36cm dimensions made of plywood, with an aperture area of 3304cm2 double glass cover and an oven’s floor area of 1225cm2 made of aluminum. Kapok wool was used to line the oven’s walls and floor serving as insulator. The solar box oven was tested at the University of Maiduguri, Borno State, Nigeria. It was tested without load to determine its stagnation temperature and to check its endurance under stagnation conditions. Similarly, a water boiling test was conducted to cook rice and beans. The results show that maximum stagnation temperature was 165.1°C and maximum overall daily thermal efficiency of 19.44% was achieved on a clear day test without reflector. The field test of the solar oven demonstrated its ability to cook rice and beans well with 1 kg of rice cooked under 2 hours, while 1 kg of beans was cooked under 1 hour 45 minutes on the same day. This performance demonstrated the suitability of Kapok wool as insulation material for solar ovens
Cloud-Based Iot Monitoring System for Poultry Farming in Nigeria
Get PDFThe monitoring of environmental parameters of poultry farm using IoT applications is no longer a new research area in the field of engineering. However, the cost of implementing most of the reviewed research work seams unaffordable to rural farmers in Nigeria. This could limit the adoption and usage of such devices. In this paper, we present a cost-effective cloud-based IoT monitoring system for poultry farming. The system uses two vital weather parameters- temperature and humidity. The methodology adopted, employed the use of DHT11 sensor (a temperature and humidity sensor) to note every change in temperature and humidity data of the farm environment. The sensed data were extracted, sampled and processed by the microcontroller before transmitting the data to a remote cloud server through the WiFi module. The cloud server (Thingspeak) received the sensed data, analysed the data and plot the data graphically. The plotted graph is viewed from a computer or any smart devices. The result indicates that temperature and humidity values range between 33-38°C and 31-33mmHg respectively. Furthermore, the results show that the device is efficient in monitoring the two environmental parameters. Therefore, the efficiency of the system will no doubt provide much quicker and accurate information about change in temperature and humidity data of farm environment
Ergonomic Analysis Of A Developed Wheelchair Using Creative Algorithm
Get PDFMobility aids are important for disabled and aged patients for transportation or replacement for walking especially in indoor and outdoor environments. To guaranty the effective and efficient use of these mobility aids devoid of any form of epidemiological conditions, the level of comfort and ease of use must be ascertained. In this research, a simple and affordable wheel chair designed in previous work was analyzed to support patients in terms of ease and comfort of use. The method adopted for this study was the use of creative algorithm. Anthropometric measures were considered in the dimensioning of the wheel chair seat. It was necessary to test how ergonomically comfortable the wheelchair was in use by deploying an effective decision metrics tool known for dealing with complex decision-making process and may aid the decision maker to set priorities and make the best decision. By reducing complex decisions to a series of pair wise comparisons, and then synthesizing the results. Our findings showed an average ergonomic rating of 0.62 which indicate a relatively high degree of comfort ability in the use of the wheelchair. The use of these wheelchairs would greatly improve the community of people who have lost some means of independent mobility thereby leading to an improvement in their self-esteem. This will enable them pursues their daily vocation and life goals. The wheel chair will also serve as a novel for medical facilities in hospitals and help facilitate movement of disabled patients in homes, schools, entrepreneurial centres and hospitals
Design and Implementation of Solar Street Light for Scarcely Electrified Areas
Get PDFStreetlights are usually powered by alternating current supply from distribution stations of the utility companies. This invariably increases the demand for power distribution from utility companies. Recent developments, however, suggest the possibility of the use of renewable energy sources to power streetlights in order to reduce the demand on the consumption rate of energy on the utility companies. Accordingly, this work considered the design and implementation of streetslights in scarcely electrified areas powered by solar energy. Using tilted solar modules, energy efficient lamps, and structural anticorrosion parts, a standalone streetlight configuration with automatic switch ON/OFF mechanism was built. The results show that streetlight powered by solar source of renewable energy cheaply generates electricity directly from sunlight without emissions, noise, or vibration. Therefore, due to the inconsistencies surrounding the generation of electricity using fossil fuels, this work offers an alternative source to power streetlights thereby reducing pressure on the national grid
Performance of a simplified model inner-tube biodigester for biomethane production for household use in Nigeria
Get PDFIn the developing countries, methane capture from manures has been encouraged by using biogas plants which are predominantly household anaerobic digesters handling manure of livestock held by an average-sized family. This paper aims to assess the performance of a simplified model inner tube biodigester for biomethane production for household use in Nigeria. This paper also evaluates the biomass conversion technologies tested in the REEF (Renewable Energy Engineering Facility) Lab at the University of Exeter, the UK and the technology readiness level and implementation in Nigeria. Cow slurry and Inoculum were used to evaluate the operational efficiency and feasibility of the model Inner tube digester, with the aim of encouraging its use and adoption in Nigeria and Africa in general to help impact on the Sustainable Development Goals (SDG) on Climate Change and Energy Efficiency targets. The model digester as an option against the use of firewood, Kerosene or Liquid Petroleum Gas (LPG) system could increase the renewable energy potential in Nigeria while retaining organic matter and nutrients for soil replenishment for agricultural purposes. The 12-litre scale Biodigester showed a characteristic pattern of optimum biogas production efficiency and performance when mixed with inoculum, which indicates its prospect for future evaluation and use