double return wind tunnel

例句：

1. 1. The double return wind tunnelis crucial for testing the performance of newmaterials.
   双回路风洞对于测试新材料的性能至关重要。
2. 2. The engineers used the double returnwind tunnel to simulate the effects of extremeweather conditions.
   工程师们使用双回路风洞来模拟极端天气条件的影响。
3. 3. The doublereturn wind tunnel was designed to test thestability of aircraft wings in high-altitude flight.
   双回路风洞被设计用来测试飞机翼在高空飞行中的稳定性能。