Heat Transfer Analysis in Internal Combustion Engine Piston Using Comsol Multiphysics: A Case Study of Tri-Cycle

This present study is aimed at analyzing the heat transfer rate of an internal combustion engines piston using finite element methods (FEM).The transient nature of heat flowing involving more than single variable, complicated method of measuring temperature across the length of the liner and ambiguous boundary conditions pose serious problems for the analysis of heat transfer rate on the piston of an internal combustion engine using FEM (Finite Element Method). This present study analyzed the heat transfer rate on the piston of a Tri-cycle engine. The studied piston was selected based on its applications in automobile and other engineering applications. The analysis was basically on the transient state forced-convection and conduction heat transfer. As initial condition, the temperature distributions were considered along the piston at a range of 523K – 673K. The parameter used for the simulation were liquid (Gasoline), Gases (Air) and Aluminium silicon UNSA96061 (Piston). The modeling and simulation were performed by using COMSOL-Multiphysics 4.3a software. The mesh optimization was undertaken by using FEM techniques to predict the maximum and mimimum temperature on the piston at every stages of simulation with time dependent. It was discovered that the temperature along the piston of the try-cycle varies with respect to time. The transient analysis revealed that the temperature of the piston at the TDC (Top Dead Center) in the first power stroke is higher compare to the subsequent power strokes, which is an indication that more heat is transfer at subsequent power strokes. Probable recommendations were later made.Self-sponsore

Parametric Studies on a Mitchell-Ossberger Turbine (Numerical Approach)

This present study focuses on some selected parameter towards designing an efficient MOT hydro turbine via MOT-model formulation, parametric analysis for optimal performance, as well as development of computational interface with Visual Basic 10 programming software.The parametric studies play important role when it comes to performance optimization of the locally manufactured Mitchell-Ossberger Turbine (MOT). Several literatures on hydro-turbine had discussed extensively on the design of MOTs as well as their advantages over the other types of hydro-turbines. But none had ever discussed extensively, the parametric studies involved in optimizing an efficient MOT. This present study focused on some selected parameter towards designing an efficient and optimal MOT. This was achieved via formulation of a turbine parametric model, development of turbine computational interface (module) and decoding of the obtained data with Visual Basic (VB) 10. The algorithm, which contains step by step solution to the problem, was developed for the program. The flow formed was designed to have a data grid view which displays data loaded into the application. The flow interface had eight buttons based on certain parametric entries. The strength of this interface lied in its codes and after data which were sorted on descending order has been loaded to the memory via Visual Basic programming software. It was discovered from the obtained results that as the angle of attack increases, the turbine power developed and the efficiency decreases marginally. The effect of the flow rate was that, it increases as other parameter increases. Then, all necessary recommendations were made.Self-sponsore

Intelligent Control for Automation of Yam Storage System Using Fuzzy Logic Controller

This paper presents the development of intelligent control technique for yam storage system based on fuzzy logic controller (FLC). The expert control of yam storage system is formulated in the form of fuzzy rules. The inputs to the controller are the outside and inside temperature, wind speed and presences of rain. The output is the window opening angle. Simulations were performed for different typical levels of input parameters and also for extreme fictitious conditions. The results shown that, the controller is capable of responding to the changes in temperature conditions by adjusting the window opening angle to keep the internal temperature within acceptable range. The controller also satisfies security requirements due to sudden changes in wind velocity and presence of rain

Ergo-effects of designed school furniture and sitting positions on students behaviour and Musculo-Skeletal Disorder in Nigerian tertiary institutions

Improper design of school furniture is one of the contributing factors to back pain among students as indicated in some studies. In the case of designing school furniture where sitting constitutes a considerable time in the school, seat becomes important for comfort. This study is carried out in three selected institutions in Nigeria to determine level of musculoskeletal disorder in students’ and the furniture that they use. 720 questionnaires with 240 students (120 boys and 120 girls) drawn from each participating institutions were administered and 675 responses were received. The results show that the number of students having MSD, accounted for 93.75%. However, the distributions of pain in the body parts in each school were different. The musculoskeletal pain, mostly concentrated on neck, right shoulders right elbow right wrist right hand, upper back and lower back. The result also reveals that most of the students are sitting on chairs with seat that are too high and too deep or too shallow and of tables that are too high. However, it is recommended that further study on effect of designed school furniture and sitting position in larger sample of students’ representative in Nigeria tertiary institutions should be carried out in order to reduce the effect of body pains

PERFORMANCE EVALUATION OF A PALM KERNE NUT CRACKING MACHINE

Palm kernel, which is one of the by- products of palm tree is of great importance to the human race and highly sought for, because it contains oil which could be consumed directly or used as raw materials for other products. The plant is mostly found in the rain forest of Nigeria where the production ofª¤? palm kernel is not the major challenge, but the production ofª¤? clean and unbrokenª¤? kernel (high grade) to be sold to the palm kernel merchants who buy and supply to companies. The development of mobile palm kernel nut cracking machine was made to reduce drudgery, to enhance processing capacity and to determine processing loss. Palm kernel nut cracking occurs when nuts are loaded to rupture without crushing the embedded kernel. The aim of this research work was to assess the performance of the developed mobile palm kernel nut cracking machine. Total sample of four thousand (4,000) palm kernel nuts were divided into five groups of eight hundred palm kernel nuts and each group was further divided into four sub-groups of two hundred (200) palm kernel nuts.ª¤? Each group of five was fed into the hopper and cracked at different shaft speeds in revolutions per minute (rpm). The shaft speeds were determined with a tachometer and it was varied on the engine by adjusting the throttle lever. In a group of five, it was replicated for four different times at the same speed. The cracking efficiency and throughput capacity were calculated. The research work showed that the cracking efficiencies at speeds of 1200, 1800, 2200 and 2400 rpm were 98ª¤¡Þ0.3, 98.5ª¤¡Þ0.08, 98.5ª¤¡Þ0.01 and 99ª¤¡Þ0.04% respectively. The throughput of the machine increased from 10.91 to 38.00 g/s as the speed of the machine increased from 800 to 2400 rpm. Also the performance efficiencies of the developed machine were 93, 94, 95, 94.5 and 94% while the overall efficiencies were 90.86, 92.12, 93.58, 93.08 and 93.06% for the set speeds. It was concluded that the overall performance of this developed palm nut kernel cracking machine were effective because it fell within the range of betweenª¤? 90 to 98% overall efficiency.ª¤

A matlab-based low-cost autopilot for autonomous helicopter development

The challenges associated with the software and hardware integration activities in development of flight autopilot system for autonomous helicopter have called for a change of tactics. The resulting effect is for example, a long time delay in autopilot system design, testing and deployment coupled with the fact that several other autonomous helicopter development tasks depend largely on availability of the autopilot system. Though, the use of off-the-shelf autopilot for a flight control system may ease these challenges, they are generally characterized with limited functionalities, and restrict the user’s design authority. As alternative approach, this paper presents the development of a MATLAB-based autopilot system for autonomous helicopter development. This approach provides an integrated design environment for rapid-prototyping of a low-cost autopilot system. The results of real-time application of the autopilot for flight data logging are presented. The performance shows the effectiveness of the developed autopilot system in small scale autonomous helicopter design and implementation. This is hope to reduce the design cycle time involves in the deployment of small scale autonomous helicopter in various civil low-cost, small payload applications

Anthropometric design of furniture for use in tertiary institutions in Abeokuta, South-western Nigeria

Students sit for most of the time on school furniturein the classroom. However, the design of schoolfurniture in Nigeria using the anthropometric dataof the users has yet to be given adequate attention.This study was carried out to obtainanthropometric data of students in higherinstitutions of learning in Nigeria for the design ofergonomics chairs and tables for use by students inthose institutions. Seven hundred and twenty (720)students in three selected institutions participatedin the study. Various body dimensions (sittingelbow height, shoulder height, knee height,popliteal height, buttock-popliteal length, statureand body weight) of the students were measuredusing standard anthropometer and 5 th, 50th, and95 th percentiles of the data obtained werecomputed using a SPSS 16.0 statistical package.The existing furniture dimensions in the selectedinstitutions were also measured. Based on theobtained anthropometric data, this paper proposesfurniture design dimensions for seat height, seatdepth, seat width, backrest height (upper), armrestand desk height for students in the selected tertiaryinstitutions. The present study may be a pointer tothe effect that in the design of tables and chairs foruse in higher institutions, the anthropometric dataof the Nigerian students were not considered. It ishereby recommended that similar study should becarried out in other sections of the country

Experimental Investigation of Lard and Tallow Oils Suitability in Turning Operation of Hypo-Eutectoid Steels

This research is aimed at evaluating the performance suitability of lard and tallow based cutting fluids as potential cutting fluids in turning of hypo-eutectoid steels using carbide cutting tool steels. This was achieved via investigation of the effect of those selected fluids on certain parameters like tool temperature, tool life, spindle power consumption, Work-piece under roughness and chip formations etc., as compared to the conventional mineral oil-based MCFs.Cooling and lubrication in machining are important in reducing the severity of the contact processes at the cutting tool-workpiece interface. Currently, there are wide scale evaluations of the use of metal working fluids (MWFs) in machining, so as to reduce the amount of lubricants in metal removing operations. The increasing awareness of the general public on the environment and health impact of mineral oil-based metal cutting fluids (MCFs) is forcing machine workshop operators to reduce their use as cutting fluids and in search for more environmental friendly animal oil-based cutting fluids. Based on this, commercially available animal oils are currently been exploited as potential oils for formulation of animal oil-based cutting fluids. It is therefore necessary to conduct machining trials to determine the suitability of these oils in metal cutting operations such as turning, drilling and milling etc. This study investigates the effect of the selected cutting fluids on certain machining parameters in turning operations of hypo-eutectoid steels using carbide cutting tool. The selected oils purchased from a local market in Ibadan, Nigeria were sieved to remove any foreign particles or dirt. The solution (water, additives, and base-oil) were mixed at an elevated temperature of 55oC in a proportion 5:1:2.The essence of the emulsifier (additive) was to prevent separation of water from oil. The steel samples obtained from a steel company in Nigeria after spectrochemical analysis, were machined on a variable speed center lathe under different machining parameters. Experimental results clearly showed that Conventional cutting fluid might be replaced with Non-conventional one like LOCFs and TOCFs as they give better performances. With slight modifications and deliberate but careful alterations in some of the components of such oils, better performing cutting fluids could be obtainedSelf-Sponsore