International Journal of Engineering Research in Africa最新文献

{"title":"Corn Row Navigation Line Extraction Method Based on the Adaptive Edge Detection Algorithm","authors":"Shengyu Ji, Yan Fei Zhang, Jinliang Gong","doi":"10.4028/p-2s3184","DOIUrl":"https://doi.org/10.4028/p-2s3184","url":null,"abstract":"Aiming at the problems of long detection time and large detection error when agricultural machinery extracts corn row navigation lines, a method of corn row navigation line extraction based on the adaptive edge detection algorithm is proposed. First, the improved super-green feature algorithm and the maximum inter-class variance method are used to automatically obtain the green feature binary image, and the morphological processing is used to improve the image quality, determining dynamic regions of interest by constraining pixel thresholds, extraction of corn edge contour using adaptive edge detection algorithm, finally, the feature points are fitted by the Theil-Sen estimation method. Experimental results show: the super-green feature algorithm reflects the green content in the image more realistically, using the adaptive edge detection algorithm to extract corn row features, the accuracy rate is 94%, and the processing time of a single frame image is 104ms. Compared with the Hough algorithm extraction and the vertical projection algorithm, the navigation line extraction accuracy is increased by 15% and 8% respectively, and the time-consuming is reduced by 258ms and 150ms respectively. In addition, the stability of the algorithm is analyzed in different environments, all with good timeliness.","PeriodicalId":45925,"journal":{"name":"International Journal of Engineering Research in Africa","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2023-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45967161","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical and Experimental Investigation of Fluidized Bed Hydrodynamics at Elevated Temperatures","authors":"F. Njuguna, Hiram Ndiritu, B. Gathitu, Meshack Hawi, J. Munyalo","doi":"10.4028/p-a41tm2","DOIUrl":"https://doi.org/10.4028/p-a41tm2","url":null,"abstract":"Fluidized bed gasifiers operate at elevated temperatures, and experimental measurements for the hydrodynamic parameters at high temperatures are difficult and time consuming, making computational fluid dynamics simulation useful for such investigation. In this study, Opensource computational fluid dynamics code, OpenFOAM, was used to investigate temperature effect on the fluidized bed hydrodynamics on a 3D fluidized bed model using Eulerian-Eulerian approach. Silica sand of particle sizes of 500, 335 and 233 m was used as the bed materials under temperatures between 25 and 400 °C. To validate the simulation model, a laboratory scale fluidized bed unit was used to conduct experiments for the same range of temperature and sand particle sizes. The results revealed that the temperature of the bed materials greatly affect fluidized bed hydrodynamics. The minimum fluidization velocity increased with the sand particle diameter but decreased with the temperature. On the other hand, the bed porosity at the minimum fluidization point increased marginally with both the temperature and the particle size of the bed materials. Further analysis showed that the expanded bed height increased with the temperature for a specific superficial velocity while the bubbles grew in size with both the air flow rates and the temperature. The numerical model results were compared with the experimental results based on minimum fluidization velocity, bed porosity and pressure drop at the minimum fluidization point. The hydrodynamic results of the numerical model were in good agreement with the experimental results.","PeriodicalId":45925,"journal":{"name":"International Journal of Engineering Research in Africa","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2023-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49514328","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental and Numerical Studies of Viscoelastic Behavior of Bituminous Mixture with a High Rate of Reclaimed Asphalt Pavement, Dune Sand and Lime","authors":"Ilhem Borcheni, T. Kraiem, Neifar Mondher, J. Néji","doi":"10.4028/p-684y63","DOIUrl":"https://doi.org/10.4028/p-684y63","url":null,"abstract":"Road construction is now a priority in the economic and social development policy of a country. The increased need to improve the infrastructure system and to counter the deficit in certain quarry gravels and non-renewable resources while saving increasingly expensive road investments, makes recourse to the use of abundant and inexpensive materials in order to reduce the use of non-renewable natural materials. The objective of this research is to predict the viscoelastic behavior of asphalt mixtures incorporating high Reclaimed Asphalt Pavement (RAP) content, allowing to reduce the consumption of new aggregates and bituminous binders, and other additives such as dune sand and lime. A new formula containing 3,7% of 35/50 penetration grade virgin bitumen, 40% of Reclaimed Asphalt, 10% of dune sand, and 1% of hydrate lime was tested and compared to the conventional formula containing 5,3% of the same virgin bitumen. To evaluate the impact of dune sand and lime addition on the mechanical behavior of bituminous mixtures containing high rates of RAP, complex modulus tests were conducted on the studied mixtures, at different temperatures and frequencies, using a two-point bending device that was developed at the National School of Engineers of Tunis. Their viscoelastic properties were determined using a Generalized Maxwell model which was calibrated by 2S2P1D model. The paper describes a three-dimensional Finite Element (FE) model developed using ABAQUS software, that is used to simulate 2-point bending tests on trapezoidal samples of the studied mixtures to determine their complex modulus and accurately predict their mechanical behavior under traffic loading at ranges of temperatures and frequencies that are not experimentally accessible. To validate the FE model, determined viscoelastic properties have then been introduced into through the Prony series and its outputs were validated by experimental measurements. Both experimental and numerical results show that the use of RAP, dune sand and lime greatly improves the rigidity of the mix at high temperatures. A suggested continuation of this work would be an investigation of the rutting resistance.","PeriodicalId":45925,"journal":{"name":"International Journal of Engineering Research in Africa","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2023-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43994727","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Scrutinization of Solar Thermal Energy and Variable Thermophysical Properties Effects on Non-Newtonian Nanofluid Flow","authors":"A. Obalalu, O. Olayemi, Salawu Olakunle, Christopher Bode Odetunde","doi":"10.4028/p-s60w3k","DOIUrl":"https://doi.org/10.4028/p-s60w3k","url":null,"abstract":"Nanofluids generate high values of convection heat transfer coefficients, low specific heat, and density, which improve the solar thermal energy performance by making it work effectively. By utilizing nanotechnology and solar thermal radiation, the modern world is moving in the direction of new technologies. Therefore, this research is communicated to explore the significance of solar thermal energy, variable properties on non-Newtonian nanofluid flow. However, to exemplify the fluid transport features of the Casson nanofluid (CF), the Buongiorno nanofluid model was utilized. Also, the Lie-group technique is used in the framework to develop similarity variables that will be used to reduce the number of independent variables in partial differential equations (PDEs) and is solved numerically by using the weighted residual Galerkin method (WRGM). The graphical findings revealed that when the variable viscosity parameter is increased, the fluid temperature decreases, while the presence of the solar radiation parameter has the opposite impact. Additionally, when the non-Newtonian parameter approaches infinity, the Casson fluid obeys the viscosity law. The report of this study will be of benefit to thermal and chemical engineering for nanotechnology advancement. KEYWORD: Solar Thermal Energy, Nanofluids, Non-Newtonian, weighted residual Galerkin method (WRGM).","PeriodicalId":45925,"journal":{"name":"International Journal of Engineering Research in Africa","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2023-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49297864","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimization of Energy Consumption of a Synthetic Ammonia Process","authors":"Favour C. Ibezim, I. I. Olateju, A. Giwa","doi":"10.4028/p-3vugm2","DOIUrl":"https://doi.org/10.4028/p-3vugm2","url":null,"abstract":"Ammonia can be produced from a wide range of raw materials such as coal, natural gas, coke and oil. Coal gasification is a process that converts biomass or fossil fuel-based carbonaceous materials into CO, H2 and CO2. A cryogenic air separation process was used to obtain oxygen from air because of high purity and high amount of oxygen, which will be used for coal gasification. For an ammonia synthesis process using pure oxygen gasification, the energy consumption of cryogenic air separation occupies a large proportion. The aim is to reduce energy consumed in the ammonia plant. The models of the process were developed with the aid of Aspen Plus. The energy consumption of the different processes was obtained through energy analysis, economic analysis and sensitivity analysis. From the three simulations, it can be seen that Simulation 3 produced oxygen with the highest purity of 0.979. From the energy analysis, the energy consumed on the total utilities in Simulation 1 was 5.626×1010 BTU/h with an energy savings of 1.55%, the energy consumed in Simulation 2 was 5.286×1010 BTU/h with an energy savings of 1.53% while the energy consumed on the total utilities in Simulation 3 was 1.425×109 BTU/h with an energy savings of 74.90%. Simulation 3 consumed the least energy. The economic analysis showed the total cost of each plant for a 10-year duration. Simulation 1 had a total operating cost of 42.083 billion USD/year, Simulation 2 had a total operating cost of 41.9615 billion USD/year and Simulation 3 had a total operating cost of 918.841 million USD/year. Therefore, Simulation 3 consumed the least cost of total operation. It can also be seen that the higher the energy consumption in a plant, the higher the total cost of the plant as Simulation 3 consumed the least energy, which justified that. Simulation 3 is the air separation plant that optimises the energy consumption, thereby reducing the energy consumed in the whole ammonia plant.","PeriodicalId":45925,"journal":{"name":"International Journal of Engineering Research in Africa","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2023-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48093574","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Application of System-Based Solar Photovoltaic Microgrid for Residential Real Estate","authors":"Edemialem Gedefaye, S. Lakeou, T. Tadiwose, Tefera Terefe","doi":"10.4028/p-zj5ao9","DOIUrl":"https://doi.org/10.4028/p-zj5ao9","url":null,"abstract":"This research explores the techno-economic potential for a predominantly renewable electricity-based microgrid serving Ethiopian residential real estate buildings, the fastest-growing sector. A stand-alone photovoltaic (PV)-Battery energy storage system (BESS)-Genset (PV-BESS-Genset) connected microgrid model, utilizing measured solar irradiation data, real-time manufacturer data for technology components, case study area daily energy consumption data, and a bottom-up approach to model demand response. The modeled system results in a $ 0.298 cost of energy (COE), reduces the 2000.34 kg/yr amount of CO2 released into the environment, and yields 1,470 kWh/yr of excess energy, which indicates that the system is the most cost-effective, ecologically friendly, and reliable, respectively. Moreover, solar PV production potential is very high onsite and can meet the onsite demand with a renewable fraction of 99.3%. However, BESS and generator production potential is substantial and provides a more balanced supply that can supply electricity when solar PV production is insufficient. These results can help to develop rules for residential real estate villages to generate their own electricity needs, distribute residential real estate's current grid energy share to other underserved areas, and lessen the issue of power outages. In an original test case, HOMER software was used to build a microgrid system based on renewable energy (RE), with the single objective of minimizing the net present cost (NPC), and MATLAB/Simulink for energy management. Thus, the system could be a benchmark for new roof-mounted solar-based technology for residential real estate buildings in Ethiopia.","PeriodicalId":45925,"journal":{"name":"International Journal of Engineering Research in Africa","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2023-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48464886","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mathematical Modeling of the Heat Generated through an Evaporator-Absorber Accompanied by Thermal Storage for the Solar Energy Applications","authors":"F. Latrache, Z. Hammouch, K. Lamnaouar, B. Bellach, M. Ghammouri","doi":"10.4028/p-3m6c59","DOIUrl":"https://doi.org/10.4028/p-3m6c59","url":null,"abstract":"An evaporator-absorber geometry allows the absorption of incident solar radiation andconverts it into thermal energy useful for the evaporation of a working fluid. The evaporator-absorberworks with two fluids: a heat transfer fluid transmitting heat to a working fluid, which, circulatesalong the thermal circuit composed of an evaporator, a turbine, a condenser and a pump. The aim ofthis research work is to analyze the heat transfer through the evaporator-absorber and to extract themathematical equations model the heat exchange process between the component elements of theevaporator-absorber: a serpentine tube, a working fluid and a cylindrical tube. In this case, theworking fluid is water, and the heat transfer fluid is air, which is heated by the thermal energyconverted from solar energy. The mathematical equations describing the heat transfer are extractedby using the nodal method and discretized by the finite difference method. Afterwards, the presentwork estimates the outlet temperature of each element of the evaporator-absorber and studies thestorage capacity of the cylindrical tube. Then, the water temperature distribution on the geometry ofthe evaporator and the required quantity of water and the number of spires to have a high outlettemperature of the water vapor are determined. As a result, the mathematical modeling estimated thatthe outlet temperature of the serpentine tube is higher than the outlet temperature of the water.Additionally, the temperature of the storage tube maintains its increase throughout the day. Thequality of the heat transfer in the serpentine tube is improved by placing the tube in a vertical positionand by adopting a lower volume of water compared to the maximum volume, which is supported bythis tube.","PeriodicalId":45925,"journal":{"name":"International Journal of Engineering Research in Africa","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2023-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47727276","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Hybrid Artificial Intelligence-Based System for Supporting Eco-Industrialization of Complex Manufacturing Processes","authors":"Chaimae Abadi, I. Manssouri, M. Abadi, A. Abadi, H. Sahbi","doi":"10.4028/p-2vxi5u","DOIUrl":"https://doi.org/10.4028/p-2vxi5u","url":null,"abstract":"Since the industrialization phase is one of the main phases of the product development cycle, an original hybrid flexible automated system is developed in this paper in order to support production eco-processes designers’ decision making. It is based on three different artificial intelligence tools, namely the fuzzy Ontologies, the cases based reasoning and the rules based reasoning, which have been integrated in one system. Actually, the proposed system is composed of different modules that are well described in details thereafter. In the end of this paper, a case of study is presented in order to illustrate the efficacy of the developed intelligent system.","PeriodicalId":45925,"journal":{"name":"International Journal of Engineering Research in Africa","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2023-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46893345","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Effect of the Geometrical Parameter and Stacking Sequence on Damage Behavior of Unidirectional Carbon / Epoxy Laminate","authors":"M. Bellahkim, Y. Benbouras, A. Maziri, E. Mallil, J. Echaabi","doi":"10.4028/p-aou909","DOIUrl":"https://doi.org/10.4028/p-aou909","url":null,"abstract":"In this work, an experimental test series was carried out in order to evaluate the influence of the geometry of the specimen and stacking sequence on macroscopic behavior and the failure modes. A CFRP prepreg unidirectional was used to perform the tested specimens according to ASTM D790 standard. Five main lay-up configurations have been analyzed: [0]12, [±30]3s, [±45]3s, [±80]3s, and [0/90]3s subjected to flexural loading. The macroscopic behavior was followed by an MTS machine equipped with a bending fixture. A digital microscope is used to follow the microscopic failure modes during loading. These laminates exhibit a more complex behavior due to coupling effects and the combination of different failure modes. However, the most predominant damage observed is delamination accompanied with matrix cracking. Furthermore, the present work has shown a linear behavior of [0]12, [±80]3s, [0/90]3s, and a distinctive behavior of [±45]3s and [±30]3s laminate under flexural loading due to its pseudo ductile behavior.","PeriodicalId":45925,"journal":{"name":"International Journal of Engineering Research in Africa","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2023-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46909612","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"International Journal of Engineering Research in Africa Vol. 64","authors":"A. O. Ibhadode","doi":"10.4028/b-o6prky","DOIUrl":"https://doi.org/10.4028/b-o6prky","url":null,"abstract":"","PeriodicalId":45925,"journal":{"name":"International Journal of Engineering Research in Africa","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2023-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139369420","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}