High-speed wind tunnel test simulation method for large-scaling grid rudder

Abstract

The invention relates to a high-speed wind tunnel test simulation method for a large-scaling grid rudder. The method comprises the steps: building three scaling models that meet wind tunnel test conditions and include a truncation model with a grid rudder, a truncation model without a grid rudder, and a full-size scale type model without a grid rudder according to an original large-slenderness-ratio grid rudder model; arranging the three scaling models respectively in a wind tunnel for simulation test under the condition of using unified balance systems to ensure the measurement precision; andacquiring test data of the three models through a wind tunnel test, processing the test data, and finally acquiring data of the original model. For the model with a large slenderness ratio and a longequal straight section, the truncation model with the grid rudder is designed, so that the model size of the grid rudder is preferentially guaranteed; meanwhile, the length of the model meets the wind tunnel test requirement, the aerodynamic characteristics of the grid rudder before and after truncation are basically unchanged, so that the machining problem and the structural strength problem encountered by a large-scale scaling grid rudder model are effectively solved.

Description

technical field [0001] The invention belongs to the field of experimental aerodynamics and relates to a high-speed wind tunnel test simulation method for a large-scale grid rudder. Background technique [0002] Generally, when the large-scale grid rudder model is used for supersonic wind tunnel tests, due to the large load of the grid rudder and the thin wall of the grid, if the scale is the same as that of the missile body, that is, the belt is designed according to a completely geometrically similar scale. The wind tunnel test model of grid rudder often encounters the following problems: [0003] (1) The thickness of the grid wall after scaling is very small, and some are even less than 0.1mm, which brings many difficulties to the model processing, and is even difficult to realize in the processing technology; [0004] (2) Due to the large load, the strength and stiffness of the scaled-down grid rudder are very weak, which basically cannot meet the requirements of the hig...

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Problems solved by technology

[0003] (1) The thickness of the grid wall after scaling is very small, and some are even less than 0.1mm, which brings many difficulties to the model processing, and is even difficult to realize in the processing technology;

[0004] (2) Due to the large load, the strength and stiffness of the scaled-down grid rudder are very weak, which basically cannot meet the requirements of the high-speed transient wind tunnel test. The model is easily damaged in the high-speed airflow, especially when the wind tunnel is started. The impact of the airflow on the model caused damage to the grid rudder, resulting in the failure of the test;

[0005] (3) After the model is scaled down, the difference between the boundary layer effect and the actual model causes the simulation of aerodynamic characteristics to be distorted, and even due to the small spacing between the grids, the airflow is blocked, and the aerodynamic characteristics of the aircraft cannot be truly simulated

After comparative analysis of experiments, it is found that the thickening of the grid wall has little effect on the normal force, but the increase of resistance is more obvious

Especially at low supersonic speed, the thickening of the grid wall reduces the flow area of ​​the grid rudder, which is prone to airflow congestion, and a strong detachment shock wave is formed in front of the grid rudder, resulting in a sharp increase in resistance and a forward movement of the center of pressure , the test data is seriously distorted

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