The main objective of the present work is to find a method increases the efficiency of the airfoil that is used for blade in wind turbine, wing in aircraft, propeller and helicopter (like NACA 4412). By overcoming the separation of flow at high angle of attacks, a slotted airfoil had been used and solved numerically through connecting the pressure side in the bottom surface with the suction side in the top surface of the airfoil to energize the separated flow. Slot exit, width and slope were considered as a parameters of slot configuration to determine the effective design of consideration. Reynolds number was taken as [1.6 x106 ] and the angle of attacks were ranged from (0o - 20o ). The numerical solution with Ansys Fluent commercial program had been used to solve a fully turbulent N.S. equations with κ-ω SST turbulence model. The method of changing variables with best one among them was adopted to find the design of the slot. The results of flow field and airfoil characteristics for solid and slotted airfoil were described and illustrated in the present work which showed that the airfoil produces higher lift coefficient value and lower drag coefficient as compared with solid airfoil. Moreover, it delays stalling angle of attack to 19o . The slotted airfoil shows an increasing in maximum lift to drag ratio up to 110% at angle of attack 18o . The most effective slot is found at 60% chord, slope 65o and width 1% chord.
In this work chemical vapor deposition method (CVD) for the production of carbon nanotubes (CNTs) have been improved by the addition of S. Steel mesh container (SSMC) inside which the catalyst (Fe/Al2O3) was placed. Scanning electron microscopy (SEM) investigation method used to study nanotubes produced, showed that high yield of two types of (CNTs) obtained, single wall carbon nanotube (SWCNTs) with diameter and length of less than 50nm and several micrometers respectively and nanocoil tubes with a diameter and length of less than 100nm and several micrometers respectively. The chemical analysis of (CNTs) reveals that the main component is carbon (94%) and a little amount of Al (0.32%), Fe (2.22%) the reminder is oxygen. It was also fou
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Several previous investigations and studies utilized silica fume (SF) or (micro silica) particles as supplementary cementitious material added as a substitute to cement-based mortars and their effect on the overall properties, especially on physical properties, strength properties, and mechanical properties. This study investigated the impact of the inclusion of silica fume (SF) particles on the residual compressive strengths and microstructure properties of cement-based mortars exposed to severe conditions of elevated temperatures. The prepared specimens were tested and subjected to 25, 250, 450, 600, and 900 °C. Their residual compressive strengths and microstructure were evaluated and compared with control samples (C
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In this research design was treated gap laser mathematically and practically Bashaddam model Raasi simple and new and we have found that there is a good match in the practical and theoretical results
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Graphic design art depends on changeable cognitive systems which their relation and items relying on the accumulation of humane knowledge and thong and the humane look to the venality and his explanation to the relation between him and the venality , then the graphic design art becomes an important item of this accumulation knowledge besides , it is on kind of knowledge kinds . The technological advancement in communication lauds to increasing in communication media and design methods , where the computer and its application in graphic design promotes the design process because of it's capalebities which lead to in creasing in production process , minimizing the cost and time and achieving creative and aesthetic aspect because of it's fe
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This research discussed analytically based on intellectual institutions and theoretical landscape theater as artistic phenomenon depends on the compounds interacting overlapping mechanism visualization and dazzling Whatever the dilemma it a set of Alaqcar differ among themselves but in the result unit intellectual holds through difference and diversity between trends and styles and ways in design theorist theatrics Valashkalah on apparently formed through variations and different points of view through the philosophy of transformation and interpretation and assignment to offer privacy.
Valashkalah pulled in the design theorist theatrical as system training to arrange time and place and in line with the interpretation of speech text an
Design sampling plan was and still one of most importance subjects because it give lowest cost comparing with others, time live statistical distribution should be known to give best estimators for parameters of sampling plan and get best sampling plan.
Research dell with design sampling plan when live time distribution follow Logistic distribution with () as location and shape parameters, using these information can help us getting (number of groups, sample size) associated with reject or accept the Lot
Experimental results for simulated data shows the least number of groups and sample size needs to reject or accept the Lot with certain probability of
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In this paper, wireless network is planned; the network is predicated on the IEEE 802.16e standardization by WIMAX. The targets of this paper are coverage maximizing, service and low operational fees. WIMAX is planning through three approaches. In approach one; the WIMAX network coverage is major for extension of cell coverage, the best sites (with Band Width (BW) of 5MHz, 20MHZ per sector and four sectors per each cell). In approach two, Interference analysis in CNIR mode. In approach three of the planning, Quality of Services (QoS) is tested and evaluated. ATDI ICS software (Interference Cancellation System) using to perform styling. it shows results in planning area covered 90.49% of the Baghdad City and used 1000 mob
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