DETERMINATION OF EXTERNAL POWER FACTORS ACTING ON AN UNMANNED AERIAL VEHICLE IN CRITICAL FLIGHT MODES

The use of modern software at the initial design stages, such as Siemens NX and FloEFD, makes it possible to design, manufacture and then operate unmanned aerial vehicles with competitive performance characteristics. This article presents calculations of the operational parameters of an unmanned aerial vehicle at the conceptual design stage, the operating external force factors at critical flight conditions for further use at the stage of detailed design and manufacturing. It gives a brief overview of the design of the developed unmanned aerial vehicle. A simplified three-dimensional geometric model of a UAV has been built. On its basis, a virtual aerodynamic analysis of the chosen design of the developed unmanned aerial vehicle was carried out in the Siemens FloEFD computer complex. The dependences of the available normal velocity and the available tangential overloads on the speed of horizontal flight are obtained. The minimum permissible horizontal flight speed is calculated. The aerodynamic coefficients of the used wing profile in the UAV design are provided. The value of the available tangential overload for different flight speeds is obtained. The dependence of the maximum inclination angle of the trajectory on the flight speed when flying near the ground is constructed. The minimum allowable take-off speed at launch from a catapult is calculated, and the allowable angle of inclination of the trajectory during straight climb is determined from this speed. The pressure distribution on the outer surface of the fuselage and the wing consoles of the unmanned aerial vehicle was obtained, with the value of the effective longitudinal force being calculated for take-off modes with different inclinations of the trajectory and for horizontal straight flight at a constant speed.