International Journal of Academic Scientific Research
ISSN: 2272-6446 Volume 8, Issue 4 (October- December2020)
All listed papers are published after full consent of respective author or co-author(s).
For any discussion on research subject or research matter, the reader should directly contact to undersigned authors.
Solving Boundary Value Problems for Partial Differential Equations Using Modified Genetic Programming
Bachir Nour Kharrat, Mohamed Khatib and Shaza Alturky
Abstract: This paper presents a modified genetic programming to find exact or approximate solution of various nonlinear boundary value problems represented by partial differential equations with boundary conditions. Genetic programming is a metaheuristic algorithm that belongs to the evolutionary algorithms, which simulates some of the ideas of natural evolution inspired by the biological evolution and forms generations of trial solutions expressed in an analytical closed form. In this work, we propose a modification of genetic programming by adding a new step at the end of each generation in which the worst individual (has the largest fitness value) is replaced by the best individual (has the smallest fitness value), with the aim of strengthening the control of the best individual through generations and guiding the exploration of the search space towards the optimum region. To demonstrate the accuracy and effectiveness of the proposed algorithm, we present many numerical examples, and the results we obtained showed the strength of the proposed technique. On the one hand, we compared our results with the simple genetic programming to demonstrate the speed of convergence through generations. On the other hand, we compared our results with classic methods to ensure the accuracy and efficiency of the proposed algorithm.
A numerical study of the effect of turbulence generators in wind turbines diffusers
Mohammad Youssef Al Hashem, Nidal Al deeb
Abstract: This research aims to determine how to collect wind energy effectively in order to increase the speed of winds that approach the wind turbine. The generation of energy using wind is proportional to the wind speed cubed. If the dynamic nature of the fluid around a turbine structure and topography were used, the wind speed would be increased. Also, focusing wind energy in the blade area will increase turbine energy output. This study relates to the use of diffusers on wind turbines to improve the wind power system and increase the payoff, and aims to determine which form of diffusers are able to collect wind energy effectively and generate energy with high efficiency from wind. A numerical study was performed on the diffuser’s influence on wind turbines using computational fluid dynamics (CFD). A comparison between the performance of the proposed diffuser equipped with ducts and a reference study of different diffusers. The results showed that the proposed diffuser gave an increase in energy output around 21% greater than all the diffusers in the reference study.
Synthesis of some new sulfonamides derived from Anthraquinone
Dr. Ayman Ramadan and Dr. Kamal Khoudari
Abstract: A convenient, simple, eco-friendly, economical and efficient one-pot synthesis of new sulfonamide compounds derived from anthraquinone is described. The reaction occurs between anthraquinone-2-sulfonyl chloride (resulted by chlorosulfonation of anthraquinone) and some aminobenzene derivatives (4-aminophenol, 4-chloroaniline and 1,4-Diaminobenzne) in the presence of Potassium carbonate as base and water as solvent at room temperature within a short reaction times, gives the corresponding sulfonamides in good to excellent yields. The structures of the new sulfonamides confirmed by spectral analysis techniques (FT-IR, ESI-MS).
Desulfurization of Syrian Petroleum Coke by Chemical Treatment
Mohammad Yahia Masri
Abstract: We studied the effect of some acidic chemicals (hydrochloric acid, sulfuric acid, nitric acid) and alkalis (sodium hydroxide, potassium hydroxide, sodium carbonate and potassium carbonate) on the desulfurization rate of Syrian petroleum coke, in order to determine the best treatment method to reduce the sulfur content in it.We carried out the chemical treatment of the petroleum coke produced by the Homs Refinery. Where we used acids in their concentrated form to perform the treatment, while we used different concentrations of alkaline solutions during the treatment. The curing was performed at normal temperature and different curing times (30, 60, 90, 120) min.The study showed that the best removal of sulfur from the Syrian petroleum coke by the chemical treatment method was done when using concentrated nitric acid where the sulfur content decreased by 48.80% at a processing time of 120 min.XRD patterns was studied to investigate the structure change by chemical treatment.
Modeling The Effect of Rotation and Traverse Speeds on Full Friction Stir Welding Process Using Coupled Eulerian- Lagrangian Analysis
Abdul Mounem Jesri, M. Jameel Alshehne, Shereen Hesso
ABSTRACT: The Friction stir welding (FSW) process is a complex bonding technique which includes many of the associated physical phenomena. This paper presents a non-linear, three-dimensional, coupled thermo- mechanical model that simulates the full phases of the welding process (plunge, dwell and traverse) considering that the internal thermal source result of thermo-mechanical coupling and interaction of the interface, depending on a CEL analysis that combines the features of Eulerian and Lagrangian analysis using the Abaqus/Explicit program. The model was used to clarify effect of changing both of the rotational speed (315,630,1000) rpm and the traverse speed (60,150) mm/min in the maximum temperature and its distribution in addition to the stresses, applied to 6061-T6 aluminum alloy. The results of this study showed that numerical model with using CEL analysis allowed the modeling of large deformations that occur during FSW for the full phases, and also highlighted the main role of the rotation and traverse speeds in determining the maximum temperature and its distribution. As a result, the model showed that the welding process with a rotation speed of 315rpm and a traverse speed of 60 mm/min is the most appropriate, where the maximum temperature reached (70-90)% of the melting temperature of alloy 6061-T6 and is the thermal range for a successful FSW process. The numerical model was verified which corresponds to the results of experimental test which was done using a vertical milling machine that simulates a FSW machine.