INFLUENCE OF STRUCTURAL GAPS ON THE AERODYNAMIC CHARACTERISTICS OF “BARS” TYPE TILTROTOR FOR AGRICULTURAL MONITORING
Precision farming technologies require regular, highly detailed monitoring of agricultural lands, producing comparable crop condition maps. Hybrid vertical takeoff and landing unmanned aerial vehicles (tiltrotors) are a promising tool for solving these problems, however, their use in drone port infrastructure places special demands on their design, particularly on clearances in the powerplant beam and hatch opening systems. The aim of the study is to numerically simulate the effect of design gaps on the aerodynamic characteristics of Bars-type tiltrotor, assess their impact on the operational performance of agricultural monitoring and develop engineering recommendations. The study was conducted using a 3D model and ANSYS Fluent package. Three gap options were considered: 0, 10 and 30 mm. It was found that crevice leaks in the hatch-to-skin zone lead to the formation of vortex structures and flow separation zones, causing a decrease in the aerodynamic quality K. The maximum K decreases from 13.1 (0 mm) to 9.8 (10 mm) and 6.6 (30 mm), with drag increasing by 10-40%. In terms of operational performance, this corresponds to a reduction in takeoff duration by 9-13% (with a gap of 10 mm) and by 29% (with a gap of 30 mm). The area surveyed per flight is reduced by 11-18 hectares and 35-40 hectares, respectively. The specific cost of monitoring increases: with a 10 mm clearance, it reaches 71-75 rubles/ha (economy segment) and 440-575 rubles/ha (high detail); with a 30 mm clearance, it reaches 92-107 rubles/ha and 564-705 rubles/ha, respectively. Minimizing technological gaps and using sealing solutions in hatch assemblies are critical measures to ensure productivity, flight regularity and cost-effectiveness of monitoring.