6 Wind and Water Tunnel Equipment
411
outside the wind tunnel, and the fan speed is controlled by a long shaft
drive of about 10 m.
The inlet of the stable section of the wind tunnel is provided with a
water circulation cooling system, which can effectively control the airflow
temperature change in the test process and make the temperature rise in
the test process very small. A honeycomb device is arranged in the middle
of the contraction section. The honeycomb device has a hexagon with
a side length of 15 mm and a thickness of 300 mm, which is made of
aluminum alloy. After the honeycomb device is a three-layer damping
network, and the distance from the outlet of the honeycomb device is l
m, 2 m, and 3 m, respectively. The damping mesh is made of 0.6 mm
steel wire with three mesh sizes of 10 meshes per square inch.
4. Japan’s high-speed railway wind tunnel with low noise
The RTRI large-scale low-noise wind tunnel was designed by the Japan
institute of railway technology in 1994 and completed and put into operation in 1996 (as shown in Fig. 6.33). It is a single-loop, open and close
wind tunnel with low turbulence and low noise, used for railway highspeed train aerodynamic and aeroacoustic test (as shown in Fig. 6.34), the
open test section of 8 m × 3.0 m × 2.5 m, silent test section of section size
20 m × 5 m × 3 m, the corresponding maximum wind speed 111 m/s
and 83 m/s, test section turbulence degree 0.2%, at 83 m/s (300 km/h) the
background noise of test section 75 dBA. The wind tunnel is composed
of a wind tunnel body, measurement and control system, power system,
model support system, lifting system, etc. The axial flow fan in the power
Fig. 6.33 Layout of RTRI large-scale low-noise wind tunnel
411
outside the wind tunnel, and the fan speed is controlled by a long shaft
drive of about 10 m.
The inlet of the stable section of the wind tunnel is provided with a
water circulation cooling system, which can effectively control the airflow
temperature change in the test process and make the temperature rise in
the test process very small. A honeycomb device is arranged in the middle
of the contraction section. The honeycomb device has a hexagon with
a side length of 15 mm and a thickness of 300 mm, which is made of
aluminum alloy. After the honeycomb device is a three-layer damping
network, and the distance from the outlet of the honeycomb device is l
m, 2 m, and 3 m, respectively. The damping mesh is made of 0.6 mm
steel wire with three mesh sizes of 10 meshes per square inch.
4. Japan’s high-speed railway wind tunnel with low noise
The RTRI large-scale low-noise wind tunnel was designed by the Japan
institute of railway technology in 1994 and completed and put into operation in 1996 (as shown in Fig. 6.33). It is a single-loop, open and close
wind tunnel with low turbulence and low noise, used for railway highspeed train aerodynamic and aeroacoustic test (as shown in Fig. 6.34), the
open test section of 8 m × 3.0 m × 2.5 m, silent test section of section size
20 m × 5 m × 3 m, the corresponding maximum wind speed 111 m/s
and 83 m/s, test section turbulence degree 0.2%, at 83 m/s (300 km/h) the
background noise of test section 75 dBA. The wind tunnel is composed
of a wind tunnel body, measurement and control system, power system,
model support system, lifting system, etc. The axial flow fan in the power
Fig. 6.33 Layout of RTRI large-scale low-noise wind tunnel