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Content available Ultralight and Very Light Helicopter Rotor Data
EN
In recent years, a significant number of one- and two-seat lightweight helicopters have come into existence, and this makes it possible to analyse parameters and determine dependencies for this class of helicopters. The knowledge of such dependencies is necessary at the preliminary design stage. The analysis performed in this paper and its comparison with the statistical data of all categories of helicopters made it possible to determine the necessary corrections in the methods of determining the parameters of the helicopter’s rotor systems.
EN
In recent years, a large number of one- to two-seat-type helicopters have appeared, raising the possibility to determine the dependencies inherent in these classes. Such dependencies are extremely necessary at the preliminary design stage, in particular, for determining the fuel mass. The relative mass of fuel depends on the required range and flight time of the helicopter, as well as on the characteristics of the engine and the required power of the helicopter. Based on statistical data, the article presents an approximate relation of the hourly fuel consumption of engines that small helicopters are equipped with. The additional amount of fuel required to complete missions has also been determined. General dependency of the fuel weight that can be used at the preliminary design stage is presented according to the analysis results.
EN
A modern main rotor, dedicated to the ultralight helicopter, has been designed and optimised. Due to assumed simplicity of the rotor design and taking into account some technological constraints, the principal purpose of the presented research was to design a dedicated airfoil which, when applied on the main-rotor blades, would influence satisfactory improvement in a performance of the ultralight helicopter, especially in fast flight. The design and optimisation process has been supported by a computational methodology. The in-house software has been used for direct and inverse design of shapes of the rotor-blade airfoils. Aerodynamic properties of the airfoils as well as the helicopter main rotor were evaluated based on both the two-dimensional and three-dimensional flow simulations conducted using the ANSYS FLUENT software that was used to solve U/RANS equations. Based on the results of conducted computational simulations of fast flight of the ultralight helicopter, it can be concluded that the newly designed main rotor, compared to the baseline, may give certain improvement in helicopter performance in fast flight. In addition, the application of this newly designed rotor may lead to increase of a maximum speed of the helicopter flight, due to the greater lift force achievable by this rotor on the retreating blade, which is favourable from point of view of keeping of a lateral balance of the helicopter in fast flight.
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