A method for simulating downburst in a boundary layer wind tunnel coupled with a wall jet and a multi-blade grid

Abstract

The invention discloses a method for simulating downburst flow in a boundary layer wind tunnel coupled with a wall jet and a multi-blade wing grid. The axial flow fan of the wall jet device is turned on to obtain a jet wind field, and the height and width of the air outlet of the wall jet device are adjusted. The angle of the air outlet adjusts the plate, thereby changing the spatial distribution of the jet wind field, so that the maximum radial wind speed of the jet wind field appears at the set height; at the same time, the wind tunnel fan is turned on to form a set flow velocity in the wind tunnel flow channel. Background wind field; coupling the jet wind field and the background wind field to obtain the downburst outflow wind field with the set spatial characteristic distribution; adjust the angle of the deflector of the deflector to change with time according to the set law, so that the The spatial characteristics distribution of the background wind field changes with time, and the flow field characteristics of the downburst outflow wind field change with time, simulating the sudden change of the downburst outflow wind field with time. It can not only simulate the spatial characteristics of the downburst outflow wind development area, but also simulate the time-varying unsteady characteristics and vortex area development characteristics of the downburst outflow wind.

Description

technical field [0001] The invention belongs to the technical field of wind tunnel simulation test, in particular to a method for simulating downburst flow in a boundary layer wind tunnel coupled with a wall jet and a multi-blade wing grid. Background technique [0002] Against the background of the deteriorating global climate year by year, downburst wind disasters occur frequently, causing serious damage to structures such as buildings, public facilities and transmission tower systems within their radius of action. The measured results show that the wind field characteristics of downbursts and typhoons, tornadoes and other wind disasters are significantly different, so the wind tunnel test has its own unique way to simulate the wind field of downbursts. [0003] The physical simulation of downburst in the wind engineering community is divided into two categories, one is to simulate the entire process of downburst development and change, and the other only simulates the dow...

AI Technical Summary

Problems solved by technology

Although the first device can generate the downburst outflow wind profile, it cannot effectively simulate the time-varying characteristics of the wind speed after the downburst is fully developed and cannot effectively simulate the vortex structure of the downburst outflow leading edge rolling up; the second Although this device can simulate the time-varying characteristics of the downburst wind speed and the vortex structure after the airflow hits the ground, it cannot effectively simulate the spatial distribution characteristics of the downburst at any deflector rotation angle.

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