This study examines the task of identifying the conditions of formation of aircraft condensation trails (ACT) during the interaction of the exhaust jet of a turbofan engine (TFE) with the environment. The method of numerical solution of the equations of gas dynamics (Reynolds equations) is applied, taking into account the nozzle shape of the considered TFEs. The calculations take into account geometric and gas-dynamic parameters that affect key processes for various types of the TFEs considered, including the bypass ratio, characteristics of internal and external flows, water vapor emissions, and others. The results obtained are necessary for the development of a criterion for the formation of stable ACT based on the degree of supersaturation of water vapor in the engine jet. The analysis of examples of the formations of ACT is carried out, based on data from the real flight tests.
О методике моделирования условий образования конденсационных следов самолетов
В данном исследовании рассматривается задача определения условий образования конденсационных следов самолетов (КСС) при взаимодействии выхлопной струи турбореактивного двигателя (ТРДД) с окружающей средой. Применяется метод численного решения уравнений газовой динамики (уравнения Рейнольдса) с учетом формы сопла рассматриваемых ТРДД. В расчетах учитываются геометрические и газодинамические параметры, определяющие ключевые процессы для различных типов ТРДД, включая степень двухконтурности, характеристики внутреннего и внешнего потоков, эмиссия водяного пара и другие. Полученные результаты необходимы для разработки критерия образования устойчивых КСС, основанного на степени перенасыщения водяного пара в струе двигателя. Проведен анализ примеров образований КСС, опираясь на данные натурных летных испытаний.
авиационный двигатель, осесимметричное сопло, конденсационный след самолета, теплообмен, газодинамика струи
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