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栅格翼大缩比模型在进行超声速风洞试验时,由于缩比模型的格栅厚度较小、格栅间距较小等问题使得模型加工困难,同时模型结构强度难以满足超声速风洞试验要求,风洞试验中无法真实模拟栅格翼模型的气动特性和飞行器的静稳定特性。针对该问题,基于超声速线化理论对栅格翼提出等效模拟方法。等效模拟方法是设计栅格翼的等效模型,该等效模型与原栅格翼模型气动特性相同。等效模拟方法处理方式为在保持栅格翼外轮廓尺寸及栅格四边之间几何角度不变情况下,按比例系数k减少栅格数,栅格间距增加k倍;保证栅格翼的格宽比不变,将栅格翼弦长增加k倍;保证栅格翼的相对厚度不变,栅格翼筋板厚度增加k倍;等效模型和实际模型纵向压心位置需保持不变。以等效模型和实际模型进行了超声速风洞对比试验,试验结果表明:等效模型和实际模型升力一致,阻力大致相同;飞行器等效模型的静稳定特性和实际模型的静稳定特性相同;栅格翼阻力对飞行器质心所产生的俯仰力矩较升力对飞行器质心所产生的俯仰力矩是小量,栅格翼等效模型在阻力上的微小差异对飞行器的静稳定性影响不大。等效模拟方法可以较好地模拟栅格翼的气动特性和飞行器的静稳定特性,同时解决了大比例缩比所遇到的加工问题和结构强度问题。
In the case of supersonic wind tunnel test, the grid wing scale-down model is difficult to model because of the small grid thickness and the small grid spacing, and the strength of the model structure can not meet the requirements of the supersonic wind tunnel test. Wind tunnel test can not truly simulate the aerodynamic characteristics of the grid wing model and the static stability characteristics of the aircraft. To solve this problem, equivalent simulation method is proposed for grid wing based on supersonic line theory. The equivalent simulation method is to design an equivalent model of the grid wing, which has the same aerodynamic characteristics as the original grid wing model. The method of equivalent simulation method is to reduce the number of grids by a factor of k and increase the grid spacing by a factor of k under the condition of maintaining the outer outline size of the grid wing and the geometrical angles between the four sides of the grid. Width ratio unchanged, the grid chord length increase k times; to ensure that the relative thickness of the grid wing the same, grid wing rib thickness increased by k times; equivalent model and the actual model longitudinal pressure center position to be unchanged. The experimental results show that the equivalent model and the actual model have the same lift and the same resistance. The static stability of the equivalent model of the aircraft is the same as that of the actual model. The grid The wing pitching resistance produces a small amount of pitching moment to the center of mass of the aircraft due to the pitching moment generated by the centroid of the aircraft. The slight difference in resistance of the grid wing equivalent model has little effect on the aircraft quasi-static stability. The equivalent simulation method can better simulate the aerodynamic characteristics of grid wing and the static stability of the aircraft, and solve the processing problems and structural strength problems encountered by large scale ratio.