LAUTECH Journal of Engineering and Technology (LAUJET)
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DEVELOPMENT OF EXTENDED SURFACE HEAT TRANSFER EQUIPMENT AS LABORATORIES TEACHING AIDS
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One of the effective ways of enhancing the heat transfer rate between a solid and an adjoining fluid is through the use of an extended surface called fin. Extended surface enhances the heat transfer rate by increasing the area of the surface through which heat is transferred. This paper presents the design, construction and testing of an extended surface heat transfer teaching equipment. Extended heat transfer equipment is made of metal rod of 10 mm diameter and length 350 mm, heater of 60 W capacity, Plaster of Paris (P.O.P) insulator, stands-support for heater, insulator and the metal rod and base flat bed of 500 mm × 200 mm × 80 mm. Experimental studies were carried out on three materials (brass, mild steel and aluminum) to determine their respective temperature distribution along an extended surface over a length of 28 cm for 2700 seconds interval at different voltage of 50, 100 and 150 volts. The theoretical analysis results were compared with the experimental results and the temperature distribution in the three materials were compared. The results revealed that, Aluminium has the highest temperature value, followed by Brass and Mild Steel at different voltages considered. The temperature increases as voltage increases, at 50, 100 and 150 volts, temperature values are 70, 113 and 157 oC for Aluminum, 65, 111 and 141 oC for Brass and 60, 87 and 100 oC for Mild Steel respectively for 2700 seconds. This explains the reason why Aluminium has the highest heat transfer characteristics followed by Brass and Mild steel. Statistical t-test analysis at 95% confidence limit confirmed that there is no significant difference between the theoretical results and experimental results. Analysis of variance, ANOVA at 95% confidence limit confirmed that, there is significant difference between the temperature gradient of the three selected material. Finally, the extended surface heat transfer equipment is affordable as produced with locally available materials; It has enhance easy maintenance, reliability and accuracy of results. It can be used as teaching aids in laboratories and research institutes
EXPERIMENTAL INVESTIGATION OF PRODUCT DISTRIBUTION FROM PYROLYSIS OF DIFFERENT WOOD SPECIES RESIDUES
No full textThe pyrolysis characteristics of different wood species residues [Ayin (Anogneissusleiocarpa), Araba (Ceibapentandra), Dongoyaro (Azadirachtaindica), Iroko (Milicia excels) andGedu (Tectonagrandis)] have been investigated in an electrically heated fixed bed batch reactor at pyrolysis temperature of 500 oC and 15 minutes residence time. Tar was trapped in an ice bath during the experiment. Product yields (tar, gas and char) were collected, weighed and expressed in percentage of the initial weight of the sample after each run. Results showed that Anogneissusleiocarpagave the highest char yield (33.3%), Azadirachtaindica and Milicia excels, the highest tar yield (42.7%) and Ceibapentandra, the highest gas yield (40.7%). For all the wood species residues, tar yields were relatively high. This was attributed to high percentage of cellulose in the wood species. It was inferred that in situations where pyrolysis oil is most preferred, Azadirachtaindica and Milicia excelsshould be considered as feedstock for pyrolysis and that pyrolysis of woody biomass at 500 oCfavoured tar yield
THE APPLICATION OF DESKTOP COMPUTER PROGRAM TO THE DESIGN OF STORM SEWER SYSTEMS FOR URBAN RESIDENTIAL LAYOUTS: storm sewer systems
No full textThe application of desktop computer to the design of storm sewer systems for urban residential layouts was investigated and outlined. The preliminary design was at full flow conditions, and manning’s formula was used for routing storm runoff through the system. The hydraulic analysis was based on the standard step-back water computational technique, which applied bernoulli’s energy equation to estimate frictional losses in the system. He determination of the appropriate pipe sizes was by trial and error procedure, which ran for several man-hours, for a multi-branch system. A desktop computer program was developed for the calculation of the pipe discharges and rainfall intensities for a selected portion of mokola residential area, Ibadan from the basic equations. The program proceeded to determine suitable pipe inlets and outlets. The computer outputs were compared with the results obtained using the conventional charts and tables in analyzing the selected area. The results produced using the Q-Basic program were more accurate, and were obtained in a few seconds
MITIGATING THE TRAFFIC CONGESTION USING MPLS ROUTING TOWARDS GREATER EFFICIENCY IN AN IP BASED NETWORK
Get PDFThis paper focuses on application of Multiprotocol Label Switching (MPLS) as a viable scheme of controlling internet traffic for greater efficiency and reliability. Graphical Network Simulator (GNS3) is utilized in the design and simulation of three different IP network routing scenarios: a network utilizing Open Shortest Path First (OSPF), one implementing both OSPF and Multi-Protocol Layer Switching (MPLS) and a network employing OSPF, MPLS and MPLS-Engineering (MPLS-TE). Performance comparison of different cases of IP routing in these networks are determined via throughput time of packets that traverse the network. Time taken for packets to traverse MPLS implemented network is shorter than that of OSPF based network. For example, the throughput times of OSPF only network for three, four and five routers network are, respectively, 64 68and 44 ms, while the corresponding throughput times in MPLS network are 56, 52 and 40 ms, respectively. In addition to that, the traffic in MPLS-TE network is easily routed through a pre-determined path without conflict, thus ensuring other internet traffics are shipped across the network un-hindered. It is shown that MPLS network addresses the challenges of internet service traffic by reducing the throughput time and allowing prioritizing of packets as they traverse the network routers
A TECHNICAL SURVEY OF POST HARVEST PROCESSING OPERATIONS OF CASSAVA IN EKITI STATE, SOUTH-WEST NIGERIA
Get PDFCassava (Manihot esculenta Crantz) is a staple root crop of the tropics. It is a major source of energy in both human and livestock diets. However, cassava is highly perishable and must be converted into stable products soon after it is harvested. This study was therefore conducted to examine the present level of postharvest processing operations of cassava in Ekiti State, South-West Nigeria. The study was carried out using a Participatory Rural Appraisal (PRA) technique. Accordingly, twelve out of the sixteen local government areas of the State were randomly selected for the study. A purposive random sampling approach was used for selecting farmers for participation in the study. Structured questionnaires were administered to 10 cassava processors per LGA to make a total of 120 respondents for the study area. In addition, the method of Focus Group Discussion (FGD) was used to obtain information on the method and level of technologies used for post-harvest processing of cassava in the area. Data were analysed using descriptive statistics. Results show that the products of cassava processing in the study area are garri, fufu, lafun and starch. 58.3% of the cassava processors process between 500 to 2500 kg of fresh cassava tubers per day with 68.3% of the processors employing a combination of traditional and modern methods to perform their processing operations. 71.6% of the respondents use head pans to move cassava tubers from point of purchase to processing facilities. The survey revealed a near absence of mechanized processing of cassava in the study area due to lack of funds by the individual processors to acquire the necessary processing machines. Accordingly, it is recommended that cluster processing facilities should be established which would allow a processor to carry out their unit operations for a fee without necessarily owning the processing equipment
STABILISATION OF NIGER DELTA FAT CLAY WITH BLEND OF BINDERS FOR SUBGRADE APPLICATION (PART 3) - TRIAL STABILISED ROAD SECTIONS IN SAMPOU, NIGER DELTA
Get PDFThe field performance of subgrade fat clay stabilised with additives and cement (PC) was evaluate by constructing trial sections along Odoni-Agbere road in Sampou, Bayelsa state. The blends mixed with the subgrade used in the study were, Drill Cuttings Ash (DCA)-PC (1:1), sand-PC (4:1), and lateralite-PC (2:1). Comparison of the dry density of cored stabilised samples with the laboratory samples showed that 100% compaction was achieved in the field for all the sections. Dynamic Cone Penetrometer (DCP) and field plate loading tests were used to determine the in-situ California Bearing Ratio (CBR) and settlement respectively. The in-situ CBR of the unstabilised and stabilised sections exceeded the targeted 15%. However, the in-situ CBR of the unstabilised section could be compromised if the soil is excessively manipulated and excess water is present. The percentage increase in settlement after two cyclic loading operations for the stabilised section ranging from -17 to 7%. This study revealed that the stability of the stabilised sections could be ensured if they are sealed on or before the 45th day after construction
ASSESSING THE LEVEL OF POWER SYSTEM SECURITY USING CONTINGENCY ANALYSIS
No full textOne of the major objectives of any electricity supply authority is to be able to supply its customers the quality product and meeting their demand at all times. One major setback in achieving this object in Nigeria is the incessant outages on the grid generator buses and transmission lines. System security involves the practices designed to keep the system operating when components fail. System security analysis involves three major analyses. These include system monitoring, contingency analysis and corrective action. In this work a D.C power analyses. In this work a D.C power flow mathematical technique has been employed to carry out contingency analysis using NEPA 28-bus Nigeria 330kv national grid network. Simulation of the effects of the outages were carried out on the network. Executed one by one, outages were introduced on two generators buses and on three transmission lines of high loading capacities. With the contingency analysis performed s explained mathematically in section 2 of this paper, the new power flows when outages were introduced are presented graphically in figures 4 and 5. Results showed that new flows (MW) went up beyond limit values on some of the lines during the outages
STATUS OF POSTHARVEST PROCESSING OPERATIONS OF SOYBEANS IN RURAL NIGERIA: A CASE STUDY OF BENUE NORTH-WEST SENATORIAL ZONE
Get PDFThis study was conducted to investigate the level of technology used for the postharvest processing and handling of soybeans in rural Nigeria using Benue North-West Senatorial Zone as case study. The approach for carrying out the study was the Participatory Rural Appraisal (PRA) technique. Data were collected using focus group discussions and questionnaires to obtain information from soybean farmers on their methods and level of technologies of postharvest processing. A purposive random sampling approach was used for selecting farmers for participation in the study. Accordingly, a structured questionnaire was designed and administered to 800 farmers from amongst who there were 591 respondents. More information was collected from eight groups of farmers who were organized into focus groups of discussants. Each focus group comprised between eight and twelve members, giving a total of 87 discussants across the study area. A total of 36 research questions were contained in the structured questionnaire while 12 questions were asked during the group discussions. Data were analyzed using descriptive statistics. The results from the research indicated that all the postharvest processing operations of soybeans namely; threshing, cleaning, drying, chemical treatment, packaging, transporting and storing were performed manually. However, a very small proportion of the farmers engaged in mechanized threshing (5.2%) and cleaning (0.3%), respectively. In certain communities such as Abwa-Mbagen in Buruku Local Government Area, some farmers did not remove broken and infected soybeans before bagging. The use of manual processing methods in the study area impacts negatively on the quality and quantity of soybeans that finds its way to the market. This constitutes a disincentive to farmers as they are unable to maximize their gains from their production efforts
MODIFICATION OF NIGERIAN BENTONITE FOR UTILIZATION IN OIL WELL DRILLING OPERATIONS
Get PDFMore than 80 bentonite clay deposit sites had been identified in Nigeria. Yet, almost all clay and additives used for drilling oil well are imported. The reason is partly that in their natural states, they do not swell while polymers in their raw forms remain unstable at high temperatures. This study aimed at evaluating the potentials of chemically modified Nigerian bentonite for application in the oil and gas industry. The Gombe bentonite from Gombe State was beneficiated using NAHCO3 and slurries were made by dispersion in distilled water. In the presence of other local additives, evaluation of the slurries was carried out on the basis of filtration loss and rheology at different temperatures (30, 60 and 85 oC) using a Central Composite Design (CCD). The clay sample was characterized for mineral and elemental compositions using X-ray diffractometer (XRD) and X-ray fractometer (XRF) while proximate analysis was carried out on the additives. At the optimum condition, the result shows a significant improvement in mud rheology and fluid loss at various temperatures which are in close agreement with the API recommended standard
APRIORI ALGORITHM APPROACH FOR AUTOMATIC TEXT PROCESSING AND GENERIC-BASED SUMMARIZATION SYSTEM
Get PDFText Processing has always existed in various forms. It makes voluminous text easily digestible, offers brief and quick overview of the subject contents and may provide critical context analysis to the reader. With the growth of digital articles in forms of news, blogs, wikis etc., there is serious need for a text processor which can adequately summarized an article or documents for the reader. This redirected and takes away the effort needed to read, assimilate and create summaries manually. This research paper proposed a system which provides unique opportunity for developing a core set text summarization system using Apriori Algorithm techniques to perform Binary Associated Rule on Data Mining. The system makes available a means of storing the automatic Generic-based summaries for future references and requirements