Hypersonic velocity blunt leading edge streaming turbulent kinetic energy inlet boundary setting method

Abstract

The invention discloses a hypersonic velocity blunt front edge streaming turbulent kinetic energy inlet boundary setting method, which comprises the following steps of S1, calculating a basic flow field, and obtaining a steady basic flow field variable; S2, performing direct disturbance wave simulation by using a numerical simulation system to obtain an unsteady flow field variable; S3, analyzing the flow field to obtain a disturbance field [phi]', and obtaining turbulent energy distribution characteristics; S4, setting a turbulent energy inlet boundary; and S5, calculating turbulence / transition and the like. According to the method, the turbulent energy equation in the turbulence model does not need to be modified, the calculation deviation of the turbulent energy equation at the shock wave downstream can be avoided by setting the inlet boundary condition, the more accurate turbulent energy inlet boundary condition is set based on a direct numerical simulation result, and the method has the advantages of reasonable calculation result, high realizability and high reliability, and can be popularized to three-dimensional flow conditions and the like.

Description

technical field [0001] The invention relates to the field of initial disturbance amplitude estimation in a boundary layer in a blunt front hypersonic flow, and more specifically, relates to a method for setting a boundary of a turbulent kinetic energy inlet of a hypersonic blunt front flow. Background technique [0002] Turbulence / transition is a physical phenomenon that exists widely in nature, and it has important scientific research significance and engineering application value in the field of aviation / astronautics. In the process of aircraft development, it is necessary to accurately calculate the location and range of boundary layer turbulence / transition, because compared with laminar flow, turbulence / transition will have a greater impact on the boundary layer, mainly showing wall friction and heat flow. They affect the aerodynamic properties of the aircraft, such as lift-to-drag ratio, range, stability, handling characteristics, as well as thermal protection and paylo...

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Problems solved by technology

It can be seen that the calculation results of the two methods are quite different. Compared with DNS, the RANS equation overestimates the turbulent kinetic energy in most of the flow field after the shock wave, and underestimates the turbulent kinetic energy in the boundary layer, which cannot correctly reflect The distribution of turbulent kinetic energy near the wall that affects boundary layer turbulence / transition calculations

Therefore, in the RANS numerical simulation of hypersonic turbulence / transition, the method of using the free-flow turbulence degree to set the incoming flow boundary condition is no longer applicable, and the free-flow turbulent kinetic energy after the shock wave cannot be correctly estimated, and a new inlet boundary setting technology is required

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