曲率连续的非轴对称短舱气动型面参数化设计方法研究

为了进一步提高短舱内外流的气动性能,基于类别形状函数方法建立了曲率连续的非轴对称短舱气动型面参数化设计方法.为评价所建立的短舱气动型面设计方法的适用性,从曲率半径分布、关键工况下的流动特性和气动性能三个方面对使用所建立的方法和基于圆锥曲线方法设计的超大涵道比短舱进行了对比研究.结果表明:与基于圆锥曲线方法设计的短舱相比...

Parametric Design Method for Aerodynamic Profiles of Continuous Curvature Non-Axisymmetric Nacelle

In order to improve the internal and external performance of nacelle, the parametric design method of curvature continuity non-axisymmetric nacelle, based on Class Shape Transformation function, was developed. This method consists of the key cross-section profile design, the longitudinal profile design, and three-dimensional modelling that the longitudinal profiles are distributed circumferentially around the nacelle centreline. To evaluate the parametric design method of non-axisymmetric nacelle, the curvature radius distribution, flow characteristics, and aerodynamic performance of the ultra-high bypass ratio(UHBPR) turbofan nacelle designed by the method developed in this paper were compared with the UHBPR turbofan nacelle designed by the method based on conic curve. In comparison to the nacelle designed by the method based on conic curve, there is no fluctuation in the distribution of curvature radius in the axial direction for the nacelle by the method developed in this paper. The local drag around the maximum area cross-section of the nacelle designed by the method developed in this paper decreases by 4.5% in cruise condition, that free stream Mach number is 0.8, and decreases by 5.5% in the condition that the free stream Mach number is 0.82. The reason for this is that the local high-velocity zone caused by fluctuations in the curvature radius around maximum area cross-section of the cowl is avoid. Compared with the nacelle designed by the method based on conic curve, the total pressure recovery coefficient of intake increases by 0.41% and the steady circumferential distortion index of total pressure decreases by 8.82% in climb condition with high angle of attack, due to the improved design method of intake.