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Missile aerodynamic design studies require flight control of an aircraft that passes through diverse flight regimes with extreme maneuvering requirements, using a minimal control surface set. These challenging goals are achieved typically using a simplified pre-design tool among thousands of body-fin alternatives. Alternative geometries found at this stage are then transferred to the computational domains, and CFD analyses are conducted to ensure aerodynamic performance. However, this new stage involves a costly and time-consuming preprocessing workload. For this reason, the number of missile geometries transferred from the pre-design stage is very limited. Considering that pre-design tools cannot provide sufficiently precise results, it is seen that this transfer mechanism should be replaced with a new method that is less costly than traditional workflow but more precise than pre-design tools. This study presents a new software tool that uses Missile DATCOM design terminology to generate solution domain and computational mesh automatically. This technology generates a remarkably high-quality structured mesh around the missile geometry. Fin control angles can be applied, and CFD analyses are performed at desired flight conditions. CFD analyses are performed using an in-house compressible CFD tool, and a good match with the experimental results is observed. [ABSTRACT FROM AUTHOR]

Copyright of SDU Journal of Engineering Sciences & Design / Mühendislik Bilimleri ve Tasarım Dergisi is the property of Journal of Engineering Sciences & Design and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The amount of energy obtained from wind turbines is increasing day by day. One of the factors affecting the power output of wind turbines is blade profiles. In this study, simulations of different blade profiles (NACA 0009, NACA 2415, NACA 4415, NACA 4424, NACA 6412, NACA 6415, NACA 24112, FX 63-137, GOE 795, NREL’s S824, SD 5060, SG6040) using Qblade software created, numerically analyzed and their aerodynamic performances were examined. Numerical analyzes were performed at angle of attack between 0°and 20° and Reynolds numbers of 5x104, 2x105, 1x106 . Blade profiles with the highest aerodynamic efficiency were determined as NACA 6412, NACA 6415 and NACA 4415, and the power outputs and performance values obtained by creating a three-bladed wind turbine from these blade profiles were found. Maximum efficiency was obtained for these blade profiles in the tip-speed ratio range of 6.5 to 7.8. As a result, the efficiency to be obtained from the turbine will be at the optimum level by using NACA 6412, NACA 6415 and NACA 4415 blade profiles in wind turbines. In this study, AG37, AH 80-140, NACA 8824 and RG-12 blade profiles, which are not available in the literature, were analyzed in order to contribute to the literature. [ABSTRACT FROM AUTHOR]

Copyright of Itobiad: Journal of the Human & Social Science Researches / İnsan ve Toplum Bilimleri Araştırmaları Dergisi is the property of Itobiad: Journal of the Human & Social Science Researches and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of SDU Journal of Engineering Sciences & Design / Mühendislik Bilimleri ve Tasarım Dergisi is the property of Journal of Engineering Sciences & Design and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

During most hot period it is possible to obtain passive cooling by decrease of surface temperatures with airflow velocities caused by wind, entering interior with the effect of pressure difference through the openings during the time intervals when the outside air is cooler than interior. This effect turns inversed when the outside air temperature is more than interiors. Shading devices used to protect from unwanted solar radiation acting on interior surfaces change the airflow effects acting interiors according to their types. The changes in volume flow rates, interior velocities and solar radiation amount can be advantageous or disadvantageous for total cooling loads according to the time interval as the interior and outside temperatures changes through the day. Determination of the combined effect of shading device efficiency through solar radiation protection strategy and natural ventilation, will give opportunity of designing optimum shading device. In validation of shading device efficiency with different types of shading device alternatives, zone gains and losses with convection, zone sensible gain and losses with ventilation, zone gains from windows and total cooling loads through specific time intervals are compared. Cooling load calculations are run through energy analysis simulation program Energyplus using heat balance calculation method. Convection coefficients, exhibiting the effects of the interior velocities which change by shading devices are calculated by using the datas of velocity measurements performed on wind tunnel with a model with 4 different types of shading device and without shading device. Heat gain from opaque interior surfaces by the effect of solar radiation are considered in Energyplus with the output of heat gain to air by convection. As opening dimensions are directly related to volume flow rates, required in calculation of sensible heat gains of zone by ventilation, it is expressed by discharge coefficients obtained by measured velocities on wind tunnel in front of the model and pressure differences between front and back openings for all alternatives. Shaded and unshaded areas occuring by solar radiation acting on facade with different shading device alternatives are considered. All these parameters of shading devices are used in Energyplus cooling load calculation process. For every alternatives 4 simulations of cooling load calculations had been done for open window and closed window in order to emerge the effects of airflows and solar radiation effects through specific times changing by effects of shading devices. The situations with shading device alternatives are classified as follows; Closed window, no shading device, 1SİM3kap.pen; with shading device, parallel to facade with 90° slat angle parallel to ground, 2.1SİM5kap.pen; parallel to facade with 45° slat angle parallel to ground, 2.2SİM9kap.pen; perpendicular to facade with 90° slat angle parallel to facade, 3.1SİM12kap.pen; perpendicular to facade with 45° slat angle parallel to facade, 3.2SİM15kap.pen, Open window, with no shading device, 1SİM3ac.pen; with shading device, parallel to facade with 90° slat angle parallel to ground, 2.1SİM5ac.pen; parallel to facade with 45° slat angle parallel to ground, 2.2SİM9ac.pen; perpendicular to facade with 90° slat angle parallel to facade, 3.1SİM12ac.pen; perpendicular to facade with 45° slat angle parallel to facade, 3.2SİM15ac.pen.… [ABSTRACT FROM AUTHOR]