| As a common cooling method for turbine blades,the research on film cooling has been continuously deepened.In recent years,research on the cooling characteristics of aero-engine turbine blades is not rare,but most of them focus on the influence of working conditions on the blade surface heat transfer characteristics and the improvement of cooling efficiency by new cooling structures.In this thesis,a new method for film cooling of 0° jet is studied,and the effect of angle on film cooling efficiency is mainly studied.This thesis will study from three aspects.First,based on a given geometric model of the turbine blades of a certain type of engine,the corresponding two-dimensional and threedimensional calculation models are established,and the heat transfer coefficient distribution and the Nusser number of the middle section of the turbine blade under numerical conditions are numerically simulated.Distribution;secondly,the effect of the opening position on the film cooling is studied at different positions on the suction side profile of the blade;finally,the film cooling efficiency of the jets at different angles and at each angle is studied.In the two-dimensional section calculation model,it was found that the average heat transfer coefficient of the suction surface is higher than that of the pressure surface.Due to the interference of the shock wave surface layer near the trailing edge,the heat transfer coefficient of the suction surface and the pressure surface rises and stagnates at the trailing edge coincidence near points.The three-dimensional airless film pore model is numerically simulated to basically coincide with the two-dimensional cross-section heat transfer coefficient distribution.In this thesis,a comparative analysis of the cooling effect and cooling efficiency of the modified position is completed.The openings are calculated at different positions on the suction side profile.It is found that the closer the modified position is to the leading edge,the better the cooling effect.This thesis also studies the related work on the effect of the hole angle of the film on the cooling of the blade film.It is found that the cooling efficiency of the 0° angle jet model is slightly higher than other angles in all schemes,and it decreases with the increase of the jet angle.By observing the temperature and pressure clouds,the cooling effect becomes worse as the angle of the air film hole increases.In summary,the model with 30° angle jet is slightly better than the model with other angles as a whole. |
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