The paper presents an investigation to the flutter speed of composite wing for different ply orientation. Structurally the composite wing was idealized as a composite beam load carrying structure. Theodorsen’s expression was used to get the 2- dimension unsteady lifting force and pitching moment in the limit of incompressible flow and subsonic speed which were integrated over the wing span. A free vibration analysis was first carried out to get the natural frequencies and mode shapes .The velocity-damping (V-g) method was used to calculate the flutter speed and the flutter frequency. A wing of unmanned aerial vehicle was manufactured from woven glass and polyester resin where the flutter speed was calculated experimentally by the wind tunnel test .The flutter speed was calculated analytically for different ply orientation, it is found that the increasing in torsion rigidity leads to increase in the flutter speed, the fiber combination with high torsion rigidity and relatively low coupling rigidity give higher flutter speed.
A study was carried out to determine the concentrations of trace metals in vegetables and fruits, which are locally available in the markets of Baghdad-samples of fourteen varieties of vegetables and fruits, belonging to Beta vulgaris, Brassica rapa, Daucus carota, Allium cepa, Eurica sativa, Malva silvestris, Coriandrum Sativum, Trigonella Foenum craecum, Anethum graveolens, Barassica oleracea, Phaseolus vulgaris, citrus reticulata, Pyrus malus, and Punica granatum. Analysis for Cd,Pb, Mn, Fe, Co, Ni, Cu and Zn were determined by flame atomic absorption spectrophotometry. The results indicated that the Malva silvestris recorded the highest concentrations of Cd and Mn while Allium cepa showed the highest concentrations of Pb and Cu. But
... Show MoreThe aim of this study was to evaluate the effects of noise exposure in certain residential districts in Fallujah city. Twenty-nine stations were selected and divided into two groups; the first group was located 50 to 100 metres from the main streets (quiet areas), whilst the second was located directly on the main streets. Noise levels were measured at a rate of three readings per station for different time periods for approximately sixty days in the year 2020. Mean values were taken in both the morning and evening using a portable sound level meter (Auto range, RS-232). The highest noise level was measured at Alforkan station for the morning reading (83.8 dB) within the second group, while the lowest noise level
... Show MorePetrographic, heavy mineral and clay mineral analyses are carried out for the sandstone and the mudstone units of Injana and Mukdadiya Formations in Zorbatiya area, Wasit Governorate, East of Iraq. The sandstones and the mudstones are nested as repeated fining–upwards successions, representing fluvial deposits. The sandstones of the Mukdadiya Formation is gravelly and on occasions becomes conglomerate. The sandstone of both formations comprises rock fragments, quartz and feldspars. The rock fragments are the dominant component consisting sedimentary, igneous and metamorphic rock fragments, accordingly these sandstone are classified as litharenite. The clay minerals of the mudstone u
... Show MoreThe research studies the synthetic sculpture techniques in the outputs of the students of the department of art education in terms of the shape, texture, content and technique, and employing this style by the students of the department of art education on the college of fine arts, university of Diyala. The research consists of four chapters: the first chapter: the research problem summarized by looking for the synthetic sculpture and its importance in the treatment the industrial wastes in our social life, according to modern synthetic techniques, in the American and European sculpture. This technique has been employed in more than one contemporary artistic direction and style.
This study is considered important for the students of t
This study is a numerical analysis of the transition process from the second to the third mode in transformer oil. In this study, it was determined how to change from the second to the third mode, which is thought to be a precursor to the process of electrical breakdown, which results in a significant loss of electrical energy and harm to electrical devices and equipment. The initiation time, length, rate of propagation velocity, and radius of the streamer discharge were determined. The transition from the second to the third mode during the electrical discharge process may lead to the occurrence of an electrical breakdown, which is one of the greatest challenges facing scientists and engineers who deal with the
... Show MoreIslamic law has relied on a number of sources in order to denote the rulings issued by them, including what is original and what is sub, and it is known to all scholars, that the Prophet's Sunnah is the second major source after the Koran, which separated the overall and devoted its year and restricted absolute. God Almighty obeyed the owner and his followers, and that his obedience of obedience to God Almighty said: (Who obeys the messenger has obeyed God) (women: 80), and then between the peasant who believes in him and his victory and follow him, he said: (and he said: And the one who was revealed with them were the successful ones (al-A'raf: 157).
It is known that the Sunnah commanded to follow is the