The aerodynamic characteristics of the forward swept wing aircraft have been studied theoretically and an experimentally investigation for the wake field generated by this configuration have been carried out. Low order panel method with the Dirichlet boundary condition have been used to solve the case of the steady, inviscid and compressible flow. Two different panel method techniques have been employed: the source-doublet and the doublet method. The thickness for the various components was considered in the study. Prandtl-Glauert similarity rule has been used to account for the compressibility effects. Experimentally, a model was manufactured from wood with body length (290mm) and main wing span was (204mm). The primary objective of the experimental work was the measurements of the wake dimensions and orientation, velocity distribution along the wake and the wake thickness and growth. The experiments were conducted to four different configurations at four angles of attack. A blower type low speed wind tunnel with solid walls was used in the experimental work. The mean velocity at the test section was (9.3 m/s) and the Reynolds number based on the mean aerodynamic chord was (0.46x105). The measurements showed the existence of a three-dimensionality behavior in the wake flow field. Interference between the canard wake and the wing wake was observed. The canard effect on the wing root area was detected as the separation at the wing root was delayed due to the canard downwash. The velocity defect and wake thickness are increased with the increase of the angle of attack. The comparison of the numerical results with the other published data showed that the method is capable of predicting the aerodynamic coefficients for complex configurations with reasonable accuracy. The source-double method was more accurate and faster than the doublet method for the same number of panels. The aerodynamic coefficients for the forward swept wing aircraft was calculated using the real wake shape measured in the experimental work. Numerical results showed that the canard extended the range of the angle of attack for the aircraft with a significant improvement for the lift curve slope compared to the aircraft without the canard.
In this paper, the homotopy perturbation method (HPM) is presented for treating a linear system of second-kind mixed Volterra-Fredholm integral equations. The method is based on constructing the series whose summation is the solution of the considered system. Convergence of constructed series is discussed and its proof is given; also, the error estimation is obtained. Algorithm is suggested and applied on several examples and the results are computed by using MATLAB (R2015a). To show the accuracy of the results and the effectiveness of the method, the approximate solutions of some examples are compared with the exact solution by computing the absolute errors.
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The new sustainable development goals set by the UN include a goal of making cities inclusive, safe, sustainable, and resilient. Cities are growing at huge rates, and conditions of deteriorating QOL̛s are increasing in the form of poor access to services, and slums are remarkable, especially in the cities of the Middle East; hence, the research problem can arise from a lack of knowledge regarding the in determination of a way to assess the resilience of cities to develop mechanisms that will improve the quality of urban life. In this study, a tool called CRF has been applied for the assessment of the city's resilience principles of health and quality of life, economics and social, infrastructure and environmental systems, and the principle
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Background: Mondor's disease means superficial thrombophlibitis of the chest wall in human, treatment is entirely symptomatic. Hot, wet dressing and anodynes may be used for pain relief.
Objective: To evaluate the role of systemic and transdermal action of diclofenac (olfen) with respect to the symptom and sign (pain, erythema along the superficial vein), and the use of Doppler ultrasonography which is a colored ultrasound used for assessment of flow of blood in vessels.
Method: The study was performed on 12 cases with Mondor's disease in middle age female patients with the involvement of lnframammary veins in all of the them (commonly affected), 4 cases had reassurance only, 4 cases had reassurance with systemic diclofenac, and th
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Tobacco products of all kinds are harmful to public health, so legislation has paid great attention to regulating the process of tobacco production and distribution, whether at the level of national or international legislation, in a way that achieves legal protection for these products, so the establishment of civil liability for tobacco companies as a result of harm to the smoker The positive and the negative provoked a jurisprudential dispute due to the specificity of the work of these companies, and the jurisprudence differed in the legal nature of tobacco companies ’liability between contractual and tort liability in a way that enables the injured smoker to obtain his right to compensation.
The Ge0.4Te0.6 alloy has been prepared. Thin films of Ge0.4Te0.6 has been prepared via a thermal evaporation method with 4000A thickness, and rate of deposition (4.2) A/sec at pressure 2x10-6 Torr. The A.C electrical conductivity of a-Ge0.4Te0.6 thin films has been studied as a function of frequency for annealing temperature within the range (423-623) K, the deduced exponent s values, was found to decrease with increasing of annealing temperature through the frequency of the range (102-106) Hz. It was found that, the correlated barrier hopping (CBH) is the dominant conduction mechanism. Values of dielectric constant ε1 and dielectric loss ε2 were found to decrease with frequency and increase with temperature. The activation energies have
... Show MoreBefore the unit environmental problems serious the issues of the environment and conservation of contemporary issues important in the developed and developing worlds, it was natural that leads increasing global awareness to alert a group of intellectuals, scientists and politicians to the seriousness of this problem and the call to take steps deeper and more comprehensive with respect to the environment humanitarian based on the study of the various elements of this environment and a greater understanding of the relationships among them, and on this basis, steps have been taken to target the environment and to identify problems and make efforts to achieve the goals I: stop the deterioration of the environment and the second impro
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