It has been shown that the XFOIL code gives the overall best prediction results. The XFOIL code, the Shear Stress Transport k − ω turbulence model and a refurbished version of k − kl − ω transition model were used to predict the airfoil aerodynamic performance at low Reynolds numbers (around 2.0 × 10 5). Selecting a suitable computational tool is crucial for the successful design and optimization of this ratio. For fixed and rotary wing applications, the airfoil lift over drag coefficient is the dominant airfoil performance parameter. At the same time, Computational Fluid Dynamics (CFD) is becoming increasingly popular in the design and optimization of devices that depend on aerodynamics. With this method, the airfoil data needs to be as accurate as possible. ❑❡②✇♦r❞s✿ Airship īlade Element Momentum (BEM) theory is an extensively used technique for calculation of propeller aerodynamic performance. Diverse concepts are revisited and the link between the airship geometry, and flight mechanics, is made for diverse propulsion system mechanisms. These include a detailed overview of past, present, and future enabling technologies for airship propulsion. Herein we have concentrated on a critical overview of propulsion mechanisms for airships. Their ability to remain aloft for long time periods have also expanded the range of mission profiles for which they are suited. Airships are also presenting themselves as green friendly air vehicles, in particular if solar powered airships are considered. The main reasons for this are related to the recent progress in technology of materials, aerodynamics, energy and propulsion. |❡❝❡✐✈❡❞ ✶✼ ❉❡❝❡♠❜❡r ✷✵✶✶❀ ❛❝❝❡♣t❡❞ ✶✽ ❋❡❜r✉❛r② ✷✵✶✷ ❆❜str❛❝t✿ After a few decades in which airships have been depromoted to the level of being only considered as a mere curiosity they seem now to reappear. It is shown that these models can be used to obtain an improved prediction of the propeller's performance. Originality/value-The work has extended the use of the post-stall models to the propeller performance prediction codes. Further comparisons including forces distribution along the blade may help to better understand this inaccuracy of the models and it will be studied on future work. However, there is a lack of accuracy in the performance prediction of some propellers. Findings-The preliminary analysis of the results shows that the propeller performance prediction can be improved using these implemented post-stall models. JBLADE contains an improved version of Blade Element Momentum (BEM) theory and it is appropriate for the design and analysis of different propellers in off-design conditions. Design/methodology/approach-Different post-stall methods available in the literature were implemented in JBLADE Software. Purpose-The purpose of the paper is to analyse different post-stall models, originally developed for use in wind turbine codes, and extend their use to the propeller performance prediction. It is shown that this new design approach allows the minimization of the chord along the blade, while the thrust is maximized. Instead of using the traditional lift coefficient prescription along the blade, the airfoil best L 3/2 /D and best L/D were used to produce different geometries. Two different approaches were used to obtain the final geometries of the propellers. The results of propellers designed with JBLADE are then analyzed and compared with conventional CFD results, since there is no experimental data for these particular geometries. In addition, the design procedure and the optimization steps of a new propeller to use at high altitudes are also described. The inverse design methodology is based on minimum induced losses and was implemented in JBLADE software in order to obtain optimized geometries. JBLADE Propeller inverse design Propeller analysis High altitude propeller CFD propeller simulation This paper presents the design and optimization of a new propeller to use on the MAAT cruiser airship.
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