In this paper, a numerical model for fluid-structure interaction (FSI) analysis is developed for investigating the aeroelastic response of a single wind turbine blade. The Blade Element Momentum (BEM) theory was adopted to calculate the aerodynamic forces considering the effects of wind shear and tower shadow. The wind turbine blade was modeled as a rotating cantilever beam discretized using Finite Element Method (FEM) to analyze the deformation and vibration of the blade. The aeroelastic response of the blade was obtained by coupling these aerodynamic and structural models using a coupled BEM-FEM program written in MATLAB. The governing FSI equations of motion are iteratively calculated at each time step, through exchanging data between the structure and fluid by using a Newmark’s implicit time integration scheme. The results obtained from this paper show that the proposed modeling can be used for a quick assessment of the wind turbine blades taking the fluid-structure interaction into account. This modeling can also be a useful tool for the analysis of airplane propeller blades.
CuO nanoparticles were synthesized in two different ways, firstly by precipitation method using copper acetate monohydrate Cu(CO2CH13)2·H2O, glacial acetic acid (CH3COOH) and sodium hydroxide(NaOH), and secondly by sol-gel method using copper chloride(CuCl2), sodium hydroxide (NaOH) and ethanol (C2H6O). Results of scanning electron microscopy (SEM) showed that different CuO nanostructures (spherical and Reef) can be formed using precipitation and sol- gel process, respectively, at which the particle size was found to be less than 2 µm. X-ray diffraction (XRD)manifested that the pure synthesized powder has no inclusions that may exist during preparations. XRD result
... Show MoreThe preparation of the title compound, C26H25N, was achieved by the condensation of an ethanolic mixture of benzaldehyde, cyclohexanone and ammonium acetate in a 2:1:1 molar ratio. There are two crystallographically independent molecules in the asymmetric unit. The two cyclohexyl rings adopt an
The aim of this research is to study the surface alteration characteristics and surface morphology of the superhydrophobic/hydrophobic nanocomposite coatings prepared by an electrospinning method to coat various materials such as glass and metal. This is considered as a low cost method of fabrication for polymer solutions of Polystyrene (PS), Polymethylmethacrylate (PMMA) and Silicone Rubber (RTV). Si were prepared in various wt% of composition for each solutions. Contact angle measurement, surface tension, viscosity, roughness tests were calculated for all specimens. SEM showed the morphology of the surfaces after coated. PS and PMMA showed superhydrophobic properties for metal substrate, while Si showed hydroph
... Show MoreThe study is about Maxwell , three dimensions of non – Newtonian fluid. Method of th Homotopy applied to analysis mass transfer and heat with thermophoresis effects. (Sc), Impact of therrmophoretic (𝜏), magnetic (M), Biot (γ), radiation (Rd),Schmidt Prandtle (Pr) parameters and ratio parameter(β) on concentration, temperature are offered in the paper.
ان دراسة الدين العام في اقتصاد ريعي شديد الارتباط بسوق خارجية شديدة التقلب يعد من الدراسات الحساسة كونها تضع امام الباحثين القيود المالية التي سيتكبل بها اقتصاد ضعيف قليل التنوع يعتمد على سوق الطاقة مما يفقد حالة الاستدامة المالية وتفقد الدولة القدرة على الوفاء بالتزاماتها المالية ، ان الحدود الامنة للدين العام يجب ان تكون بنسبة لا تتجاوز 60% من الناتج المحلي الاجمالي حسب اتفاقية ماسترخت الخاصة بمجلس الاتحا
... Show MoreThis research sheds light on the morphological structure of nouns and verbs in the novel "ASTONISHMENT" by the novelist Aharon Applefield by analysing selected models from the novel in a morphological analysis in order to identify the most important morphological features of this structure according to a statistical analytical approach.
The morphological structure is the main pillar of the linguistic structure of the literary text. Morphology is the science that studies the word, by which its structure and original letters are known, and the change that has occurred to it. The aesthetics of the fictional text is reflected in this structure, through which the writer conveys his ideas and narrations to the reader. The research
... Show MoreThis study refers to the development and characterization of silver oxide nanoparticles obtained by X-ray diffraction, nanostructured silver oxide was used in order to calculate the micro strain and crystal size by Halder-Wagner method and by relying on X-ray diffraction diagram of the nonstructural silver oxide, where the results of the crystal size and the micro-strain were 4nm and 0.33 respectively. Other analysis techniques, such as the Size-strain plot, The X-ray diffraction study confirmed that the crystalline nature of silver oxide nanoparticles has a cubic structure. Through the X-ray diffraction results, the crystal size was calculated using Debye-Scherrer and Williamson-Hall methods. Halder-Wagner (HW), Size-strain plot, D
... Show MoreElectrical distribution system loads are permanently not fixed and alter in value and nature with time. Therefore, accurate consumer load data and models are required for performing system planning, system operation, and analysis studies. Moreover, realistic consumer load data are vital for load management, services, and billing purposes. In this work, a realistic aggregate electric load model is developed and proposed for a sample operative substation in Baghdad distribution network. The model involves aggregation of hundreds of thousands of individual components devices such as motors, appliances, and lighting fixtures. Sana’a substation in Al-kadhimiya area supplies mainly residential grade loads. Measurement-based
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