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.
Objective: The present study was aimed to develop a pH-triggered in situ gel for local release of lidocaine hydrochloride (lidocaine HCL) in the buccal cavity to improve the anesthetic effect of this amino amide drug which has very high water solubility. The formulations were introduced to the oral cavity as a spray to improve compliance and for easier administration.Methods: In this work, two grades of carbopol (934 and 940)-based in situ gel spray were designed. The formulations containing lidocaine HCl 5% were prepared by mixing different concentrations of carbopol with xanthan gum. Eight formulations were investigated and evaluated for gelation capacity, spray angle, volume of solution delivered per each actuation, rheological p
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This research sheds light on the major sins (fornication and sodomy) as two crimes that are prohibited by the divine laws, including its conclusion by the Islamic Sharia. Major sins so that life and the universe are organized, and the individual lives a life of chastity and purity free of filth and filth. The Islamic message included a set of preventive measures and remedial methods that, if the ummah were to apply them, they would live a decent life full of noble goals.
This study was aimed to produce AuNPs biologically using Klebsiella pneumoniae and study their synergistic effect with some antibiotics.Technologies of nanoparticles are quick and are employed in many applications in biomedicine. The potential of metallic nanoparticle as an anti-microbial agent is greatly investigated which considered as an alternative method to reduce the challenges of multi-drug resistance microbes. The present study discusses the novel approach to synthesize nanoparticles involving eco-friendly synthesis of gold nanoparticles using Klebsiella pneumoniae and study their effect as antimicrobial spectrum .Also study synergism effect of gold nanoparticles with antibiotic against Acinetobacter baumannii. These approac
... Show MoreThe rapid change in economic is a serious challenge facing all countries around the world, even developed ones. This challenge is increasing as the world enters the age of knowledge in which different knowledge and technologies have emerged and the distance between the emergence of scientific knowledge and its actual application on the ground has been reduced as well as the growing role of science and technology in community development. One of the most important technology amongst these technologies is nanotechnology, where this technology plays a major role in the development of products and modern devices and reduces cost with quality improvement. This technology is cross-cultural, requires a comprehensive knowledge structure and depe
... Show MoreHigh smoke emissions, nitrogen oxide and particulate matter typically produced by diesel engines. Diminishing the exhausted emissions without doing any significant changes in their mechanical configuration is a challenging subject. Thus, adding hydrogen to the traditional fuel would be the best practical choice to ameliorate diesel engines performance and reduce emissions. The air hydrogen mixer is an essential part of converting the diesel engine to work under dual fuel mode (hydrogen-diesel) without any engine modification. In this study, the Air-hydrogen mixer is developed to get a homogenous mixture for hydrogen with air and a stoichiometric air-fuel ratio according to the speed of the engine. The mixer depends on the balance between th
... Show MoreExperimental study on the effect of cylindrical hollow cathode, working pressure and magnetic field on spatial glow distribution and the characteristics of plasma produced by dc discharge in Argon gas, were investigated by image analyses for the plume within the plasma. It was found that the emission intensity appears as a periodic structure with many peaks appeared between the electrodes. Increasing the pressure leads to increase the number of intensity peaks finally converted to continuous form at high pressure, especially with applied of magnetic field, i.e. the plasma is more stable with the presence of magnetic field. The emission intensity study of plasma showed that the intensity has a maximum value at 1.07 mbar pressure and decre
... Show MoreIn this study, an analysis of the synoptic characteristics, causes and mechanisms of Kahlaa tornado event was carried out. This tornado occurred on 10:30 UTC (1:30 pm Iraq Local Time) on 14 April 2016 to the north of Kahlaa town in Maysan governorate. We analyzed surface and upper charts, weather conditions, the damage indices, the dynamical features and the instability of the tornado. The analysis showed that there was a low pressure system which was an extension of the Monsoon low in addition to a supercell thunderstorm and a jet stream aloft. The cold trough and high relative vorticity at 500 hPa level, the humid warm wind blowing from the south and the dry cold wind from the north contributed to the initiation of the tornado. Accordi
... Show MoreTwo different composite materials were prepared by stir casting method of AA 6061 alloy as a matrix reinforced with two addition different ceramic materials Al2O3 and B4C of grain size 20 µm by 2.5, 5, 7.5 and10% in weight. The composite material with aluminum alloy as a matrix possesses a unique mechanical properties such as: high specific strength and hardness, low density, and high resistance to corrosion and friction wear. This composite is widely used in automotive parts space and marine applications.
Pin-on-disc technique was used to calculate the wear rate for each addition of Al2O3 and B4C particles. Rockwell hardness test and
... Show MoreAbstract Study aim: to assess the influence of care burden for children with leukemia on their mothers` psychosocial status. Methodology: A Descriptive study, conducted at two pediatric hospitals in Baghdad city. A purposive sample of (60) mothers was participated in the study after obtaining their consent form. The instrument of the study was used to assess mothers` psychosocial status in addition to their sociodemographic characteristics. The data was processed and statistically analysed by SPSS program version 23. Result: the result of the study showed mothers have (81%) in self esteem, (77%) in psychosocial distress, (80%) for social interaction, and (76%) for social isolation. There were association between mothers` psychosocial status
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