Numerical Study on Ventilation and Cooling of Aeroengines Using Similarity Theory

For aeroengines, the use of digital design technology is beneficial to shorten the development time and reduce the development cost. This paper takes the ventilation and cooling system of the core nacelle of a civil turbofan engine with a large bypass ratio as the object. It numerically analyzes heat transfer characteristics of the system, and obtained the empirical formula of product surface heat transfer based on similar criteria, which supports the research of aeroengine similarity design and intelligent model making technology. The study found that the intake Reynolds number of the bleed air hole increases, and the convective heat transfer coefficient of the wall of each section shows an obvious increase trend, when the Reynolds number increases to a certain level, the effect of continue to increase the Reynolds number to transfer heat to the casing surface is no longer obvious. When the model size decreases, the proportion of radiant heat transfer increases, so the empirical formula of flow heat transfer criterion relation without considering radiant heat transfer criterion is no longer applicable.