ABSTRACT The study addresses the stability and control of nuclear systems with emphasis on the Supercritical Water Reactor (SCWR) as proposed in the Generation IV International Forum. The literature on the stability and control of the SCWR is presented. A Computational Fluid Dynamics code, STAR-CCM+, is used to study the flow stability problems in circular channels, fuel bundle slices with and without heating structures. Some of the effects of numerical discretisation, turbulence model effect...
ABSTRACT The GHARR-1 is in the final stages of converting its HEU (90.2 %) fuel to LEU (13 %) fuel. Due to the differences if the LEU core design as compared to that of the HEU; fuel density, dummy arrnagement, number of fuel elements, this study was carried out characterize the neutron spectrum at the irradiation sites of GHARR-1 to ascertain the impact of the conversion on the neutron spectrum. This was done theoretically using the MCNP5 code. The neutron spectrum parameters (a and f ), neu...
Abstract Power plant stability at lower loads is becoming ever more important, highlighting the increasing requirement for the development of advanced models and tools to analyse and design systems. Such tools enable a better understanding of the thermo-fluid processes and their dynamics, which improves the ability to specify and design better control algorithms and systems. During low load operation and transients, such as start-up and shutdown, the required water flow rate through the evapo...
ABSTRACT The City of Cape Town is the most congested city in South Africa, with Johannesburg coming in second. Capetonians are spending 75% more time in traffic because of the congestion during peak hours, thus reducing time spent on leisure and other activities. Due to population growth, increasing car ownership and declining capacity of rail infrastructure, Cape Town’s road infrastructure will continue to be under severe pressure if the status quo is maintained. Research shows that conges...
Abstract The electric vehicle relies on electric motors for propulsion. In this report, the case was made for the induction motor as a suitable candidate for this tractive application. Being able to control the electric motor invariably implies efficient control of the vehicle. This work reports the six-step operation of the constant volts/hertz (V/f) control technique for voltage fed induction motor drives. Mathematical equations supporting the principle is discussed and the drive is modell...
Abstract This thesis aims to extract d-axis machine parameters of a 214 MVA high-speed turbogenerator using well-established offline techniques. MATLAB/SIMULINK tool has been utilized to model the generator and perform sudden short-circuit (SSC) tests. Because constant speed operation of the generator is vital consideration for the accuracy of SSC tests for parameter extraction, this thesis has employed an arrangement of 2 DC motors operating alongside a drive system, which is configured to ...
ABSTRACT The development and utilization of energy has led to environmental degradation with associated health hazard. Hence the trust of this project is to optimize energy mix in a reliable, affordable, available, safe, efficient, effective and sustainable way at control cost subject to environmental constraints. In other to achieve the desired goal, the optimization model is derived with unit cost of each of the various energy sources as the objective function and environmental impact as c...
ABSTRACT Due to the scarcity of water in Nigeria, there is a need for an irrigation system that conserves water for efficient crop production. In the course of this research work, a drip irrigation system was constructed and tested with the sole aim of using cheaply available materials to determine the variation in emitter discharge at different heads and also, the coefficient of uniformity of the system. A test was carried out by determining the volume of water discharged by each of th...
ABSTRACT This study examined the experimental analysis of sandcrete block production by using different sources of sharp sands in Enugu and Ebonyi State of South-East Geo-Political Zone. As a result of the increasing cost of block production, many manufacturers and builders have resorted to using samples of sharp sand from different locations without appropriate consideration of the material constituents of the samples thereby, resulting in poor and undurable concrete blocks production. In ...
ABSTRACT This work proposes a switching technique for cascaded H-Bridge (CHB) cells. A single carrier Sinusoidal PWM (SCSPWM) scheme is employed in the generation of the gating signals. A sequential switching and base PWM circulation schemes are presented for this fundamental cascaded multilevel inverter topology. With these proposed concepts, it is now possible to generate equal average switching signal patterns in all the constituting power semiconductor switches. This results in equal swi...
ABSTRACT The growing demand for energy has resulted in the research and development of clean and renewable energy technology and related materials. In this work, the effect of acetic acid on the structural, optical and electrical properties of undoped ZnO was studied. Also, the effect of indium and gallium dopants on the structural, optical and electrical properties of ZnO was studied. The ZnO thin films were deposited on glass substrates at 400°C using the spray pyrolysis deposition techniq...
The qualities of Nigerian graduates have been a source of concern.The polytechnics have come under criticisms as lacking capacities to turn out competent technologists. However,this paper picks this issue from a different angle.The graduating grade so fa sample of engineering students in apolytechnic were correlated with their entry performances (Secondary Certificate and Matriculation Examinations) over three sessions. The correlation was weak (r=0.13;Ho:=0 accepted at =0.025) whil...
ABSTRACT In this study the factors affecting the capacity of indoor powerline networks were investigated. In order establish the factors, first the frequency response at various loads was determined using Anatory et al model. Then the mathematical approximation was used to determine the PSD of noise in dBm/Hz. The mathematical approximation represented the noise of a typical indoor channel similar to that obtained by Liu et al for indoor channel. Since, because of the limitations on the tran...
Abstract Biomass waste to energy conversion systems were traditionally installed on rural farms to manage manure disposal and mitigate odour. These systems provide heating and electricity and are increasingly viewed as sources of revenue. Poorly operated or sized systems will not realise revenue. For farms that would like to install such systems, there is no tool available that optimises the systems prior to determination of their commercial viability. As such, there is a need to optimise ...
ABSTRACT The detection and location of faults on power transmission lines is essential to the protection and maintenance of a power system. Most methods of fault detection and location rely on measurements of electrical quantities provided by current and voltage transformers. In this work, current sensors and voltage sensors were used in the prototyped model of the data collection device. Training data were collected by taking into consideration variables of a simulation situation like fault...