Математичне моделювання реверсу гвинтовентилятора ТРДД з надвисоким ступенем двоконтурності

This study investigates a ducted propfan in reverse mode, considering the influence of air bypass from outside the duct or air leakage after the propfan impeller. The size of the bypass windows and the dependence of the air flow rate through the bypass windows of a ducted propfan in reverse mode when changing the flight speed and the dependence of the reverse thrust of a ducted propfan in reverse mode, considering the influence of air intake from outside the duct or air leakage after the propfan impeller, are the subjects of the study. The study object is a ducted propfan with rotating blades of the impeller of a bypass ratio turbojet engine with an ultra-high bypass ratio (m = 20). The bypass windows are located behind the propfan impeller. The purpose of this study is to study the reverse thrust of a ducted propfan in reverse mode, considering the influence of air intake from outside the duct or air leakage after the propfan impeller. The flow simulation in a ducted propfan with rotating blades of the impeller of an ultra-high bypass ratio turbojet engine with an ultra-high bypass ratio was conducted under standard atmospheric conditions in the reverse mode in the range of the M number from 0.1 to 0.25 for the variants of the absence of bypass windows and with an increase in the relative area of the bypass windows from 0 to 0.63. The dependences of the change in the air flow rate through the bypass windows of the ducted propfan when changing the speed and the reverse thrust characteristics of the ducted propfan in the reverse mode were obtained. The flow visualization in several modes is presented, which confirms the efficiency of air bypass behind the propfan impeller. The scientific novelty and practical significance of the research results lie in the fact that new data were obtained on determining the rational size of the bypass windows and the dependence of the change in air flow rate through the bypass windows of a ducted propfan in reverse mode on the change in speed and thrust characteristics of the reverse of the ducted propfan in reverse mode, considering the influence of air intake from outside the hood or air leakage after the propeller fan impeller.