Development of a 5kw Francis Turbine Runner Using Computation Fluid Dynamics

A small scale Francis turbine runner for a turbine located at Awba dam in the University of Ibadan with designed head and flow rate of 6m and 0.244m3/s is designed. The basic design of the Francis turbine runner is completed based on basic fluid dynamics turbo machinery principles. A 2-D and 3-D steady state, single-phase CFD analysis is conducted for the runner, stay vanes, guide vanes, spiral case and draft tube of Francis turbine using two commercial CFD codes (ANSYS FLUENT and Solidworks Flow Simulation). The dimension of the runner is obtained from empirical formulas using the available head and flow rate. The runner is then optimized using CFD analysis to get required shape and performance. Performance of turbine is predicted at different guide vane openings. Cavitation and flow separation analyses are also conducted using a 2-D, steady state and two-phase (water vapour and liquid water) in order to reduce their occurrence in the designed runner. A hydraulic efficiency of  68.2% was obtained.Keywords: Fluid dynamics, hydro-turbines, cavitations, CFD, flow separatio

Design of a Solar Water Heating System for Kuti Hall, University of Ibadan, Ibadan

This work presents an energy audit to determine daily heating load and energy eliminated by Solar Water Heating (SWH) system. Monthly average daily irradiance in plane of solar collector and Cold water temperature calculated from weather data collated to determine heating load. Mathematical model was developed based on heat transfer, thermal and optical and energy performance of collector. The absorber plate area, dimensions of solar collector, pipes‟ diameter, mass flow rate, fluid inlet, outlet temperature, the overall loss coefficient are considered as variables. Optimization procedures formulated and models developed were transposed into a MATLAB computational program. Components selection was also carried out. Data was generated by increasing the absorber plate area from 1 to 20m2 and the mass flow rate of fluid from 0.001 to 0.009 kg/s. The optimum values recorded for the area and mass flow rate are 18.33m2 and 0:0087 kg/s respectively. Increasing the mass flow rate above the optimum determines the non change of Exergy efficiency. Heat load per day in KUTI Hall is 636.7MJ and the collector area obtained is 91.64m2. 6.95MJ of heat is needed per meter square. The SWH system can cater for heating load of 115MJ/day which will sufficiently heat up 600 litres of water from 240C to 700C.Keywords: Water Heater, Collector, Energy Audit, Absorber, Plat

Development of a Metal Kiln for the Production of Charcoal from Waste Wood

The need for preservation of fresh fish for commercialization purposes has attracted research efforts especially from fish scientists. There are a number of energy sources utilized for fish processing, such as electrical and wood. Due to the abundance of vegetation in the university community, there abound waste woods from felling of aged timbers; this offers potential for wood charcoal production. The focus of this study is to develop a pilot plant for wood-charcoal kiln to be employed for fresh fish processing. Relevant mathematical formulations were employed for determination of kiln model dimensions prior to fabrication of kiln parts. The wood charcoal produced in the kiln was used for fresh fish processing and the combust emission was analyzed at peak carbonization stage. Mathematical computation of Heat transfer analysis of the charcoal-making process in the kiln was undertaken using MATLAB. The wood average mass of 35 kg was combusted in the kiln to make charcoal to obtain a minimum and maximum wood conversion efficiency of 0.105 and 0.314 respectively were obtained. Maximum carbonization temperatures in the range of 350–400°C were also observed. Computational results agreed with experimentally observed data and revealed that incorporation of an insulating material would have an adverse effect on the carbonization process. The study established that the design upon modification would be environmentally safe, viable and an economic alternative for processing fish farm produce.Keywords: Production, Smoking, Charcoal, Kiln, Desig

Design of an Efficient Incinerator for Independence Hall, University of Ibadan

The menace constituted by improperly disposed solid waste has led to an increase in growing awareness towards solid waste disposal alternatives. The case of Independence Hall in University of Ibadan, Nigeria is not different as delay in the ultimate collection of the waste makes the storage site become an eye-sore and this justifies the need for an alternative waste disposal system. It is the objective of this work to design a low-cost and efficient household unit incinerator for the hall. A field survey which spanned over four weeks was conducted. Proximate and ultimate analysis of each waste component, their respective high heating values and the combustion rate of domestic waste were obtained from literature. These data were used in carrying out proximate and ultimate analysis of the waste. The survey reveal that Independence Hall waste consists essentially of eleven components which are polythene (42.28%), mixed paper (21.72%), rags (3.48%), leather (0.29%), Rubber (0.58%),glass/ceramics (0.87%), garbage (5.21%), metals (2.03%), wood (4.93%), Plastics (8.69%), ripe leaves (9.63%), and that the average daily waste generated, moisture content and loose waste density are 31.2kg, 22% and 68.9 kg/m3 respectively. From proximate analysis, moisture content, combustible component are ash 17.2%, 72.7% and 8.3% respectively. The LHV per kg of waste is 41303.91 KJ while the furnace temperature is 996.27oC. A low-cost incinerator which is environmentally friendly and capable of incinerating 4kg of waste per batch at minimal burn-down time was designed with a cyclone separator as the emission control device. Keywords: Solid wastes, Disposal, cyclone, Incinerator, Emission, University community

Production and characterisation of biochar from different farm wastes

Three different carbon-rich materials called biochars were produced from three different agricultural wastes using slow pyrolysis technique. The abundance of these wastes (maize cobs, maize stovers and cocoa pod husks) in most farms in Nigeria informed their choice. In this study, the biochars produced were characterized to determine their inherent nutrient potentials as soil amendments for high crop productivity. The percentage mass of biochars obtained were: maize cobs 27.6%, maize stovers 26.0% and cocoa pod husks 22.3% at 332°C, 361°C and 500°C temperature respectively. The highest carbon content (511.1 g kg-1) and total nitrogen (12.1 g kg-1) were obtained from maize stovers biochar, while cocoa pod husks gave the least values. Highest pH (11.98), moisture content (14.0%) and phosphorus (1150.0 mg kg-1) were however obtained in the biochar from cocoa pod husks. We concluded that cocoa pod husks, maize cobs and maize stovers are feedstocks for making biochars of different physical forms and properties and these biochars are potential sources of valuable soil amendments in a humid tropical soil environment.Keywords: Biochar, charcoal-fired reactor, cocoa pod husks, maize cobs, maize stovers, slow pyrolysis