Ефективна тяга співвісного закапотованого гвинтовентилятора

The subject of this study was the effective thrust of a ducted coaxial propfan. The object of this study was a ducted coaxial propfan of a turbopropfan engine. Purpose: This study estimates the change in the effective thrust of the ducted coaxial propfan from the M value in the cruising mode of operation. In order to achieve this goal, the following tasks were set and solved: to obtain the dependence of the thrust force of a ducted coaxial propfan for Mach numbers ranging from 0.5 to 0.7 at cruising altitude; obtain the dependence of the resistance force of a ducted coaxial propfan for Mach numbers ranging from 0.5 to 0.7 at cruising altitude. The present work uses methods from numerical experiments and the theory of heat engines. The Ansys CFX software was used to simulate the flow. The block mesh of the studied models was built in the ICEM module, considering the boundary layer. Research results: This study assessed the effective thrust of a ducted coaxial propfan in the cruising operating mode. As the Mach number increases from 0.5 to 0.7, the thrust force of the ducted coaxial propfan decreases, ranging from 46.2 to 37.4 kN. The drag force, in contrast to the thrust force, increased from 0.5 to 0.7 Mach numbers from 12.2 kN to 17.5 kN, respectively. In the Mach number range from 0.5 to 0.7, the effective thrust force varies from 34 kN to 20 kN, respectively. An important factor in calculating the thrust performance of ducted propellers and propfans is the drag force. The resistance force for the studied modes of the ducted coaxial propfan ranged from 26.3 to 46.7%. Visualization of the velocity field showed that a zone of reduced speed was formed in front of the first row and behind the second row of the propfan. An aerodynamic wake also appears behind the duct. In the future, it is planned to study the effect of the duct thickness on the effective thrust of a coaxial propfan. Scientific novelty and practical significance of the obtained results: new data were obtained on the drag force of a ducted coaxial propfan at a flight altitude of 7 km in the Mach number range from 0.5 to 0.7. The obtained data can be used for the modernization of turbofan engines.