ABSTRACT The effect of blank/punch diameter ratio (draw ratio) in deep drawing on earing for different gauges of Al 1200 sheet was studied. Using 60, 62, 64 and 65mm diameter circle blanks and 33mm diameter punch die, fully annealed Al 1200 sheets of gauge thicknesses 0.6 to 2.0mm were subjected to deep drawing on an ErrichsenR cup drawing machine. The results showed that with increase in sheet thickness, the smaller is the draw ratio that would draw the sheet. For 0.6-0.9mm sheet thickness,...
ABSTRACT Chaos is one of the most important behavioural modes exhibited by dynamical systems and refers to the unpredictable, seemingly random, motion of trajectories of a dynamical system. In recent time, non-linear dynamics and chaos have become familiar in the technical vocabulary of most sciences and technology due to the various applications of chaos in these areas. Chaotic systems display chaotic behaviours only for specific range of values of their parameters. It is therefore important...
ABSTRACT This study investigated thickness requirements for field fabricated (large) spherical liquefied natural gas (LNG) pressure vessels using the finite element method. In the FEM modeling, 3-dimenisonal analysis was used to determine thickness requirements at different sections of a 5-m radius spherical vessels based on the allowable stress of the material as given in ASME Section II Part D. Shallow triangular element based on shallow shell formation was employed using area coordinate sy...
ABSTRACT The amazing development in the thermal engineering literature during the last three decades has opened up totally new and challenging research areas. One of them is the determination of surface area of .metallic bodies. Modern advancements in surface area determination (SAD) have enabled the calculation of areas of several complex shapes. More recently, problems .in ragged metallic bodies (RMB) have evolved. , Research into SAD primarily aims at calculating the cost of coating or ele...
ABSTRACT This paper proposes a set sequencing heuristic solution for the travelling saIesman problem (TSP). It attempts to first select, preferably a set of M smallest elements of the TSP matrix and then form a sequence. A computer code of the procedure was developed in Fortran 77 and used to examine its efficiency and relative effectiveness. It was found to be as effective as, but more efficient than the best of the nearest neighbourhood heuristics.
ABSTRACT Aircraft disaster has been in existence since air was conquered by man as a means of transportation. 487.5 million and 874.4 millions of cumulative departures and flight hours respectively have been estimated since 1959. Analysis of aircraft failure based on 5,149 on-board fatalities recorded shows that 13% of total aircraft accident was caused by mechanical faiIure while loss of control was responsible for over 3 1% of onboard fatalities. Aircraft accident is known to be most fatal ...
Abstract Surface tension is an important property that affects the behavior and characteristics of reservoir fluids.. It impacts the capillary pressure and fluid dynamics in porous media. This study, investigated the surface tension of Contaminated Niger Delta crude oil at varying temperatures. Laboratory tests were carried out on samples from four fields in the Niger Delta using DuNouy Tensiometer under standard conditions. The results show that for Niger Delta Crudes of gravity between 25 ...
ABSTRACT A previous paper on developing a national capability for the manufacture of activated carbon from agricultural waste by the same authors was considered. In the said paper, the process flow diagram for the manufacture of Granular Activated Carbon from three agricultural wastes namely coconut shell, oil-palm shells and sugarcane bagasse was provided and the plant’s economic analysis done. The objectives of this study were to investigate selling price reducing options and profitabilit...
Abstract Scheduling models based on efficient resources utilization without sufficient consideration for customer satisfaction or vice-visa is inadequate in many real-life multi-criteria scheduling problems. This work was aimed at the development of a bi-criteria algorithm for the simultaneous optimization of Makespan (Cmax) and Number of tardy jobs (NT) in a single machine problem with Sequence dependent set-up time. An existing single criterion algorithm, the Set Sequencing Algorithm, was ...
Abstract The design and construction of a flat plate solar collector is presented in this paper. The solar collector was designed to power adsorption refrigerator using activated carbon/methanol pair. Design was such as to provide simplicity and yet ruggedness for harsh operating environment in the tropical climate of Nigeria. For methanol desorption, the collector must reach a maximum temperature of at least 100"C. Performance results showed that the maximum temperature of 10aoC attained in ...
ABSTRACT Poultry production is one of the major contributors to global environmental degradation. Currently, livestock raised for meat uses about a third of global ice-free terrestrial land and produces 18% of global greenhouse gas (GHG) emissions. This is more than ·the global transportation sector (FAO, 2006). Livestock production is also one of the mail). drivers of deforestation and degradation of wildlife habitats. Due to increasing population size and per capita meat consumption 'in th...
ABSTRACT This study investigated the relationship between velocity of sound and properties of natural gases under different equations of state and the operational implications on acoustic gas metering. The velocity of sound was related to the thermodynamic properties of natural gas using both the Soave-Redlich-Kwong (SRK) and Peng-Robinson (PR) equations of state and applied to 5 wet and 5 dry natural gas samples from the Niger Delta at different conditions of temperature and pressure. Predic...
ABSTRACT Low cost and minimum emission of green house gases are two of the key advantages of using agricultural wastes as fuel in a bubbling fluidized bed combustor; however this advantage could be neutralized if significant cost and energy is spent on processing prior to usage of the waste, therefore if processing stage could be circumvented without compromising effectiveness and efficiency, a substantial operational cost saving could be achieved when using biomass as fuel in a commercial sc...
ABSTRACT The characteristics of flow over side weirs are taken into consideration to verify the discharge coefficient for subcritical flow conditions under the assumption of constant specific energy. The main channel discharge, length of weir crest and sill height of the weir are treated as controlled variables. The discharge coefficient Cd is found to depend 011 the Upstream Froude No 171 and also on the ratio of sill height to upstream flow depth S/Yl . Simple linear regression analysis was...
ABSTRACT Optimal allocation of products to downstream locations is a major requirement for minimizing the distribution costs associated with supply chain systems. Unfortunately many supply chain managers rely on, their intuition and feelings to make these allocation decisions. In this study a mathematical model was developed for minimizing the distribution cost in a multi-product 2-echleon supply chain system. The distribution system of a leading bottling plant in Nigeria was studied to under...