Numerical method for simulating wingtip vortex flow of aircraft

Abstract

The invention relates to a numerical method for simulating wingtip vortex flow of an aircraft. According to the characteristics of incompressible flow, two different forms of forces are added into a momentum equation to improve the precision of numerical simulation of one type of flow fields giving priority to vertical motion. The two forms of forces include a corkscrew force of vorticity in a gradient direction of change and a viscous dissipation force of the vorticity in the gradient direction of change. According to the method, integral computation on the corkscrew force in the gradient direction of change of the vorticity in a computational grid is transformed flux calculation on a force on the boundary of the computational grid, so that the spatial dispersion of the force can have a high-order-accuracy format; and simultaneously, the viscous dissipation force in the gradient direction of change of the vorticity is maintained by a source item of the momentum equation, thereby improving the astringency and stability of a numerical solution. As the forces adopt different amplification coefficients, the accuracy of the vorticity can be further maintained, and the vertical motion of wingtip vortex can be simulated more accurately.

Description

technical field [0001] The invention relates to a numerical method in the application field of computational fluid dynamics (CFD: Computational Fluid Dynamics), in particular to a numerical method for simulating wing tip vortices of an aircraft. Background technique [0002] When the aircraft is flying, at the tip of the spanwise direction of the finite wing, that is, at the tip of the wing, because the wing has a certain angle of attack, the pressure on the upper and lower surfaces of the wing is different, which will cause airflow under the wing The flow around the wingtip and up the wing creates a vortex. Such as figure 1 shown. The vortex extends from the wingtip shedding to the downstream direction of the incoming flow, forming a spiral-shaped flow pattern in the aircraft wake. The wingtip vortex field is a vortex-dominated flow field (Vortex-dominated Flows). If the flying Mach number of the aircraft is less than 0.3, the flow field around it can be regarded as an i...

AI Technical Summary

Problems solved by technology

[0009] 2. The spatial discrete precision of the added vorticity is limited and cannot be further improved;

[0010] 3. The

Images