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Cycloidal rotors, also known as cyclogyros, are horizontal axis rotary-wing machines with potential for Vertical Take-Off and Landing aircraft applications. The paper aims to devise and validate a new semi-empirical analytical model that is capable of assisting in the structural and aerodynamic design of cyclogyros.

The analytical model comprises a purely analytical kinematic sub-component that is used for analyzing the structural feasibility of the rotor. Several geometrical parameters are assessed, e.g. the oscillation schedule of the blades as a function of the properties of the pitching mechanical system. The dynamic sub-component of the model is used for estimating the rotor thrust production and power consumption. This sub-component is semi-empirical and uses a calibration function that was devised using the available experimental data.

For a set of initial conditions and geometrical parameters, the model is capable of providing a real animation of the cyclogyro operation. It is shown that the motion of the blades does not comply with the requirements of a perfect cycloidal curve. The study concerning the simulation of the virtual camber effect on the drum blades, with and without the pitch effect, shows that the virtual camber strongly depends on the chord-to-radius ratio and on the aircraft advance velocity.

A new analytical model capable of assisting in the geometrical and aerodynamic design of cyclogyros is here proposed. The model is capable of providing approximate estimations of the cyclogyro thrust production and power consumption under operating design conditions.

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.

Different post-stall methods available in the literature were implemented in JBLADE software. JBLADE contains an improved version of Blade Element Momentum theory, and it is appropriate for the design and analysis of different propellers in off-design conditions.

The preliminary analysis of the results shows that the propeller performance prediction can be improved using these implemented post-stall models. However, there is a lack of accuracy in the performance prediction of some propellers. Further comparisons including distribution of forces along the blade may help to better understand this inaccuracy of the models, and it will be studied in future work.

The work has extended the use of the post-stall models to the propeller performance prediction codes. It is shown that these models can be used to obtain an improved prediction of the propeller’s performance.

The aim of this article is to: provide an overview of the role of organizational simulators as essential tools to assess, at early stages of the planning phase, organizational objectives and strategy; propose recommendations on how to advance the subject area in terms of research and development; demonstrate that aeronautical concepts can be applied in the organizational context.

The article refers concepts and theories related with the subject and presents a methodology for social investigation, which was used in this research.

Organizational simulators have a fundamental role in organizational self-awareness because they help to control the organization's vital parameters, in a proactive manner, considering the creation of different scenarios that allow, beforehand, a predictive assessment.

The research provides empirical evidence of use in the operational domain of the Portuguese Air Force and also an example of the valuable collaboration between real operations use and academia research. It also offers an insight, by using the metaphor “Flying the Organization”, on how flying concepts can be applied in the organizational context.

The research lab was done using Microsoft Excel in what was related to the simulator development. All relevant data was gathered from organization's information systems (IS) and inserted into Microsoft Excel. Future implementations should be integrated with the organization's IS.

This article contributes to the “state of art” of organizational simulators by providing a real case and provides both the entrepreneurial and academia communities for conducting future actions within this subject. The article also provides value to organizational management actors on how organizational simulators can be applied.