In order to improve the effectiveness, increase the life cycle, and avoid the blade structural failure of wind turbines, the blades need to be perfectly designed. Knowing the flow angle and the geometric characteristics of the blade is necessary to calculate the values of the induction factors (axial and tangential), which are the basis of the Blade Element Momentum theory (BEM). The aforementioned equations form an implicit and nonlinear system. Consequently, a straightforward iterative solution process can be used to solve this problem. A theoretical study of the aerodynamic performance of a horizontal-axis wind turbine blade was introduced using the BEM. The main objective of the current work is to examine the wind turbine blade’s performance under specific initial and boundary conditions. In this study, NACA 4415 airfoils were selected to do this investigation. The turbine blades were divided into small segments to calculate the forces acting upon each segment to assess their impact on the final wind turbine blade design. An extensive and critical analysis of the chosen wind turbine was performed, including lift, drag, shear force, and bending moment calculations. Based on the computations, the values of total thrust force, torque, and power generation values for the optimal wind turbine were 3755.9 N, 1834 Nm, and 30.122 kW, respectively. Furthermore, a significant finding emerges from the analysis, indicating that the largest difference in power occurs at r/R=0.8, amounting to 5.5239 kW. The new Matlab code was validated. The key contribution of this study lies in enhancing turbine efficiency and reducing fatigue losses through optimizing wind turbine blade design to obtain the highest efficiency level. The outcomes demonstrate that the newly implemented MATLAB code exhibits exceptional accuracy in assessing aerodynamic performance, enabling efficient wind turbine blade design optimization.
Objective: preparing educational units for the magnet poles strategy in learning the spiking skill in volleyball, and identifying the effect of the magnet poles strategy in learning the spiking skill in volleyball for female students.Research methodology: The experimental design with two equal experimental and control groups with tight control was also adopted in the pre- and post-tests. The boundaries of this research community are represented by fourth-grade middle school students at Basra Girls' Middle School (2024-2025), whose total number is (90) students, distributed by nature into 4 sections. Sections (A-B) were determined by lottery, so that Section (A) represents the experimental group and Section (B) represents the control
... Show MoreIn this research, damping properties for composite materials were evaluated using logarithmic decrement method to study the effect of reinforcements on the damping ratio of the epoxy matrix. Three stages of composites were prepared in this research. The first stage included preparing binary blends of epoxy (EP) and different weight percentages of polysulfide rubber (PSR) (0%, 2.5%, 5%, 7.5% and 10%). It was found that the weight percentage 5% of polysulfide was the best percentage, which gives the best mechanical properties for the blend matrix. The advantage of this blend matrix is that; it mediates between the brittle properties of epoxy and the flexible properties of a blend matrix with the highest percentage of PSR. The second stage
... Show MoreThe excellent specifications of electrodes coated with lead dioxide material make it of great importance in the industry. So it was suggested this study, which includes electrodeposition of lead dioxide on graphite substrate, knowing that the electrodeposition of lead dioxide on graphite studied earlier in different ways.
In this work the deposition process for lead dioxide conducted using electrolytic solution containing lead nitrate concentration 0.72 M with the addition of some other material to the solution, such as copper nitrate, nickel nitrate, sodium fluoride and cetyl trimethyl ammonium bromide, but only in very small concentrations. As for the operating conditions, the effect of change potential and temperature as well
... Show MoreMatrix acidizing is a good stimulation process in which acid is introduced into the reservoir near the wellbore area via the wellbore or coil tubing. In the oil industry, formation damage is a prevalent problem. Bypassing wellbore damage by producing wormholes in carbonate reservoirs is the main purpose of acidizing the matrix of the formation. When doing lab tests, scientists are looking for a wormhole-inducing injection rate that can be used in the field. Meantime the ongoing works on the Ahdeb oil field's Mishrif reservoir, several reports have documented the difficulties encountered during stimulation operations, including high injection pressures that make it difficult to inject acid into the reservoir formation; and only a few
... Show MoreThis study aims to determine the extent to which Palestinian elites use digital diplomacy to confront the Israeli narrative by exploring the motives for usage, patterns, essential digital diplomatic tools, and achieved satisfactions. The study adopted a survey methodology and employed a questionnaire distributed to a sample of 110 Palestinian political and media elites.
The study arrived at several key findings, including: Palestinian elites allocate a substantial (%67) of their efforts towards employing digital diplomacy as a response to the Israeli narrative. The foremost platforms employed for this purpose are Facebook and Twitter. The primary motivation for utilizing these digital platforms is to present
China is moving towards building the largest economic power in the world, so what does this mean economically and politically for Europe, America, the Middle East and the Arab world? This project is called the expansionist Chinese Marshall Plan which is a revival of the old Silk Road in a new way. It represents the aspirations of the Chinese people and their president, Xi Jinping, to build a transport route from Asia to Europe and a railway plan to transport goods. The purpose of this is to develop the economic growth model, expand into new markets, promote the Chinese currency, and expand economic and political influence in the areas covered by the Chinese initiative. Equal opportunities in distributing investments to these countries, a
... Show MoreArabic text categorization for pattern recognitions is challenging. We propose for the first time a novel holistic method based on clustering for classifying Arabic writer. The categorization is accomplished stage-wise. Firstly, these document images are sectioned into lines, words, and characters. Secondly, their structural and statistical features are obtained from sectioned portions. Thirdly, F-Measure is used to evaluate the performance of the extracted features and their combination in different linkage methods for each distance measures and different numbers of groups. Finally, experiments are conducted on the standard KHATT dataset of Arabic handwritten text comprised of varying samples from 1000 writers. The results in the generatio
... Show MoreRecently, many materials have shown that they can be used as alternatives to chemicals materials in order to be used to improve the properties of drilling fluids. Some of these materials are banana peels and corn cobs which both are considered environmentally- friendly materials. The results of the X-ray diffraction examination have proved that the main components of these materials are cellulose and hemicellulose, which contribute greatly to the increasing of the effectiveness of these two materials. Due to their distinct composition, these two materials have improved the rheological properties (plastic viscosity and yield point) and reduced the filtration of the drilling fluids to a large extent. The addition rates used for each o
... Show MoreIn this work we fabrication holographic optical element diffraction grating thickness 40?m and mirror90?m by using dichromated gelatin,to perform that we have to use the Nd-yaG laser doubling frequency of wavelenght (532)nm and its powers of (80)mWatt.we have studyed the thickness and concentration dichromat effect in mirror reflaction ,effect of angle of reconstruction beam in band width and diffraction efficiency ,study effect gelatin hardener of the diffraction efficiency.