ЕКСПЕРИМЕНТАЛЬНЕ ДОСЛІДЖЕННЯ ХАРАКТЕРИСТИК ВЕНТИЛЯТОРІВ МАЛОРОЗМІРНИХ БПЛА

<jats:p>The subject of this study is the determination of the performance characteristics of small UAV fans across a wide range of rotor speeds. The objective of this work is to improve the accuracy of flow-parameter measurements in the inter-blade passage of a tandem fan with a combined toroidal-spiral blade tip by digital modeling and verification of the results on a specially designed experimental test bench. The task: to propose an experimental test bench for studying the power characteristics of UAV thrust fans of both enclosed and open types. The problem of selecting a fan for a power plant is quite complex, given the wide range of aircraft for various purposes, especially small-sized ones. Sometimes it is necessary to choose from a wide range of model fans that can be produced quite quickly using a 3D printer. Therefore, the development of an experimental setup that, while featuring simple design solutions, would meet the necessary operational requirements and specified metrological characteristics is undoubtedly a pressing task. The following results were obtained. The experimental test bench proposed (and tested) by the authors is technologically simple and enables rapid determination of comparative and operational characteristics of fans in the relevant model range, with the aim of selecting the optimal option from the customer’s perspective. A method for determining the main energy-efficiency characteristics of fans for small UAVs is presented (the experiments were conducted primarily on tandem fans; in which both rows of blades are connected by a toroidal-spiral tip). A distinctive feature of the method and the developed experimental setup is that it allows for the separation of the thrust and torque measurement channels, which ensured their independent measurement. This made it possible to obtain scientifically sound simulation results through practical verification. During the design of the setup, particular attention was paid to the channels for recording efficiency and power factor, as these parameters were measured indirectly—their values were calculated from other measured parameters rather than determined directly. It should be noted that the experimental test bench was designed to allow for the study of both open and enclosed fans. Another distinctive feature of the setup is that it allows one to obtain fan performance characteristics, such as the thrust dependence T=f(n), power – P=f(n), and efficiency η=f(n) over a wide range of rotor rotational speeds (n=0…50,000 rpm), which is very important for small UAVs. The results obtained were used to derive comparative characteristics of a model series of fans for a UAV engine with a thrust of 50 kH, which are currently the most prevalent, especially in combat conditions. Further expansion of the system’s functional capabilities is planned. Therefore, during its design, reserve channels for measuring parametric information were incorporated.</jats:p>