Understanding how wing geometry and internal structural configuration influence vibration behavior is essential for ensuring the aeroelastic stability and structural integrity of modern aircraft. This study presents a comprehensive numerical investigation of the modal and deflection characteristics of aircraft wings with different geometries (symmetric tapered planform and swept-back) and spar configurations (box and I-section) using the finite element method (FEM) in ANSYS Mechanical APDL R.15. Six NACA airfoil profiles (0024, 2411, 2416, 2424, 4412, and 4421) with angle of attack 9° under 50 m/s speed and 1,100 kg pay load were analyzed under identical aerodynamic and material conditions using linear elastic and small-deformation theory. Aerodynamic coefficients were determined using thin airfoil and Prandtl’s lifting-line theories, while modal parameters were extracted through high-order 20-node solid brick elements and verified through mesh convergence analysis. Based on the results obtained, the tapered wings show a natural frequency nearly 22% higher than swept-back wings. The matter that confirms the dominant influence on geometric stiffness. On the other hand box spar wings reveal 9.5%–22% higher frequencies but showed 20%–30% higher deflection than I-section spars, demonstrating their superior torsional compliance and enhanced energy absorption under the dynamic effect. On the contrary, I-section spar resulted in higher bending stiffness and lower deformation, especially in higher-order modes. Based on airfoil series, the more the thick NACA 0024 as well as 2424 profiles revealed the highest levels of stiffness, based on 6 th mode frequency that exceeded 250 Hz, but the thinner cambered sections like NACA 4412 and 4421 exhibited compliance and limited rigidity against torsion. Based on the findings, the obtained increase in the natural frequency and the reduced deflection with stiffer geometries reflect improved resistance to aeroelastic instability like flutter onset. A statistical analysis using ANOVA verified that the geometry of the wing has a statistically more significant effect on modal response than the spar type although both have a significant influence on vibration behavior. Furthermore, the result of analysis concludes that the taper wings reinforced with spars type I-section give the most balanced combination of weight efficiency, stiffness and stability against vibration for the aircraft type medium payload.
This paper investigates the issue of surface-type effects on traffic noise in Baghdad. Since the raw materials for both flexible and rigid paving are available from local sources, the decision on selecting the type of paving which depends on the budget of the project and the road's importance and function. Knowing that for high traffic volumes and a high percentage of heavy vehicles, rigid pavement is more suitable compared to flexible pavement. In Baghdad, some highways consist of flexible pavement and others of combined pavement (flexible segments and rigid segments), so the study of the effect of surface type on traffic noise becomes an important matter. This study selected three highways: one with flexible pavement a
... Show MoreThe predisposing factors and their effect on the increasing of vulvovaginal Candidiasis have been studied in this research. The result indicated that the highest of infection with vaginal Candidias was in the age of women with age of (21-30years) with vaginal itching and discharge, also the results revealed that the pregnancy was the main predisposing factor. The percentage of the infected pregnant Ladies was 33.7% followed by the women who used the IUCD and OCP 22.1%, those who used steroids 5.2% comparing with control women (without predisposing factors).The results also indicated that the most cases of infection were during the third trimester of pregnancy (where the rate of infedion) was 53.9%.-OCP- Oral Contraceptive Pills-IUCD- Intrr
... Show MoreThe performance of the pavement in terms of vehicle safety and tire wear is affected by the friction behavior of the pavement. To highlight the main characteristics that affect the production of better friction resistance of the pavement surface in this work. The micro-texture and macro-texture of the asphalt surface of Baghdad Airport highway were studied using two methods: (sand patch method and the British pendulum test). The sand patch was examined by drawing sand grains of a specific volume, while the micro-texture was analyzed using a BPT under dry and wet surface conditions. All data obtained from the two examinations were analyzed and modelled statistically using SPSS 25 software. Results show that skid resistance of pavemen
... Show MoreBackground: Osteogenesis imperfecta (OI) is a rare congenital condition that results in bone fragility, recurrent fractures, and various extra-skeletal manifestations. Currently, intravenous bisphosphonate is the mainstay of medical treatment in OI. Objective: To identify the effect of current management strategies on Iraqi children diagnosed with OI. Methods: A retrospective study enrolled OI patients who were registered in Central Child Teaching Hospital, Baghdad, Iraq, from January 2015 to December 2022. We enrolled confirmed OI cases (either clinically and/or radiologically) who received cyclic pamidronate therapy for at least 3 cycles. They neither received other types of bisphosphonates nor underwent surgical intervention. Res
... Show MoreA number of pulsed experiments have been carried out using a high-voltage circuit containing R,L, and C in certain arrangements. A spherical spark gap of steel electrodes was used as a high-current switch operated by a voltage of up to 8kV and triggered in both self-triggering and third-electrode triggering modes. Current measurements were carried out by using both current-viewing resistor and Rogowski coils designed for this purpose. Typical current waveforms have shown obvious dominating inductance effect of the circuit components in an underdamped oscillation. The behavior of the circuit impedance was studied by recording both pulsed current peaks and the charging voltages when currents of up to 2.5kA were recorded. The dur
... Show MoreRating systems for evaluating the sustainability of communities are an essential tool that is increasingly applied throughout the developed world to set criteria indicators to optimize the physical, social, economic, and environmental potential within such communities. Rating systems vary based on existing disparities among societies and their unique building and physical planning practices. Iraqi cities lacked the adaptation of a formal methodology or sustainability rating system to correctly measure the built environment’s sustainability indicators. This research attempts to review the most substantial rating systems to measure the sustainability of communities worldwide to form a
The Mesopotamian soil is muddy and fertile, and so from ancient eras Iraqis used mud in their building, settlements and architecture in different methodologies according to the nature and the function of the building that was either in its pure form or by mixing it with other materials such as straw . also as raw bricks in different ways either for the whale building or parts of it, or for the finishing parts such as roofing for instance. In this research these different forms and methodologies will permeate through out a chosen examples of historical building, rural buildings and settlements and ancient buildings as well as some current uses of mud in the structures and building in standing cities, this in order to conclude some
... Show MoreObjectives: The study aims to identify the quality of life level in schizophrenic patients and to find out the
relationships between the quality of life and some of personal characteristics for those patients with
schizophrenia.
Methodology: A descriptive correlation analytic design was used by using the assessment technique on sample
of 100 schizophrenic outpatients, who were selected purposively (non-probability sample) during the period
10/ 3/2013 - 1/ 12 /2013. The study was conducted on the schizophrenic patients in an out patient psychiatric
clinics at Ibn-Rushd; and Al-Rashad Psychiatric Teaching Hospital; Baghdad Teaching Hospital, and Al-Kadhimya
Teaching Hospital. Self administrative questionnaire was used
In this work, As60Cu40-xSex thin films were synthesized, and the pulsed laser deposition method was used to study the effected partial replacement of copper with selenium. The electrical characteristics and optical characteristics, as indicated by the absorbance and transmittance as a function of wavelength were calculated. Additionally, the energy gap was computed. The electrical conductivity of the DC in the various conduction zones was calculated by measuring the current and voltage as a function of temperature. Additionally, the mathematical equations are used to compute the energy constants, electron hopping distance, tail width, pre-exponential factor, and density of the energy states in variation zones (densities of the energ
... Show MoreThe aim of this paper is to measure the characteristics properties of 3 m radio telescope that installed inside Baghdad University campus. The measurements of this study cover some of the fundamental parameters at 1.42 GHz. These parameters concentrated principally on, the system noise temperature, signal to noise ratio and sensitivity, half power beam width, aperture efficiency, and effective area. These parameters are estimated via different radio sources observation like Cas-A, full moon, sky background, and solar drift scan observations. From the results of these observations, these parameters are found to be approximately 64 K, 1.2, 0.9 Jansky, 3.7°, 0.54, and 3.8 m2 respectively. The parameters values have vital affect to quantitativ
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