An Automatic Trimming Method for 3D Whole Machine Numerical Simulation

Abstract

The invention discloses an automatic trimming method for three-dimensional whole machine numerical simulation, comprising the following steps: S1, generating an original calculation grid of the three-dimensional whole machine; the original calculation grid includes splicing grid blocks; S2, reading the original calculation The spatial point coordinates and boundary conditions of the grid, and the spliced ​​grid blocks are numerically simulated according to the read spatial point coordinates and boundary conditions to obtain the pitch moment coefficient under the current elevator surface declination angle; S3, according to the current elevator surface declination angle The lower pitch moment coefficient determines whether the elevator surface reaches the trim state. If the elevator surface does not reach the trim state, adjust the deflection angle of the elevator surface, and repeat steps S2 to S3 until the trim state is reached. The invention realizes the automatic trimming of the declination angle of the elevator rudder surface by performing numerical simulation on the splicing grid blocks of the three-dimensional whole machine, and the whole process does not need manual intervention, which is convenient and quick.

Description

technical field [0001] The invention relates to the field of surface and space grid generation in computational fluid dynamics, in particular to an automatic trimming method for three-dimensional full-machine numerical simulation. Background technique [0002] Currently, in CFD (Computational Fluid Dynamics), in order to meet the needs of the design unit, it is often necessary to obtain the aerodynamic characteristics of the entire aircraft shape in the trim state (zero pitch moment) at different Mach numbers and different angles of attack. The shape of the whole machine can keep the pitching moment of the whole machine zero through the deflection of the elevator surface on the flat tail, but under different Mach numbers and different angles of attack, the deflection angles of the elevator surfaces that meet the trim state of the whole machine are different, and the value of the CFD needs to be calculated determined during the iterative process. This requires a method of fa...

AI Technical Summary

Problems solved by technology

For the mainstream structural grid method, due to the inherent geometric properties of the structural grid itself that are difficult to automatically generate, there is no related full-machine automatic trimming technology in the CFD field.

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