Numerical simulation method for aircraft hood hinge constraint ejection separation

Abstract

The invention discloses a numerical simulation method for aircraft hood hinge constraint ejection separation. Two sets of flow field grids are generated based on an aircraft shape model, a hood in the grid A is in seamless contact with a projectile body, and the grid B is an overlapped grid and comprises a projectile body sub-grid and a hood sub-grid; according to the flight condition of the separation window, the grid A is used for flow field calculation; after the flow field converges, flow field parameters are extracted and interpolated into the grid B to serve as an initial flow field for separation simulation; and unsteady separation simulation calculation is carried out by using the grid B based on an overlapped grid technology and a rigid body six-degree-of-freedom motion equation. A flow field is simulated by solving a fluid control equation; and motion simulation is realized through the overlapping grids and the rigid body six-degree-of-freedom motion equation. When a simulation termination condition is reached, calculation is terminated. According to the method, the difficult problems of flow field initialization, hinge modeling, ejection force modeling and the like are solved, the separation simulation process is combed, and engineering application is facilitated.

Description

technical field [0001] The invention belongs to the field of aircraft aerodynamics, and relates to a numerical simulation method, in particular to a numerical simulation method for aircraft hood hinge-constrained ejection separation. Background technique [0002] Modern missiles, rockets, etc. usually place the payload in the fairing. Whether the hood can be safely and quickly separated from the main body as scheduled is directly related to the success or failure of the flight mission. In engineering, a hinge is usually installed between the hood and the missile body to make the separation trajectory controllable; the catapult is used to give the hood an initial velocity to facilitate rapid separation. The currently used hood is generally a thin-walled shell structure, which maintains an airtight and three-dimensional shape with the projectile before opening, forming a closed inner cavity where the flow stagnates; after opening, the flow field is quickly established, the in...

AI Technical Summary

Problems solved by technology

The currently used hood is generally a thin-walled shell structure, which maintains an airtight and three-dimensional shape with the projectile before opening, forming a closed inner cavity where the flow stagnates; after opening, the flow field is quickly established, the initial conditions have a large influence, and the aerodynamic interference effect is strong. It also involves the combined effects of aerodynamic force, gravity, hinge force and ejection force. At present, engineering generally uses experimental methods for research, and the numerical simulation of the separation process is relatively difficult.

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