Scalling of Wind Tunnel Models; Safety Issuesin Wind Tunnel Handling — Lesson 6

This lesson covers the different types of similarity, including geometric, kinematic, and dynamic similarity, and their role in scaling internal models in aerodynamics. It also discusses the safety issues in handling wind tunnels, both low and high speed. The lesson provides a detailed explanation of each type of similarity, their implications, and how to achieve them. It also highlights the importance of safety measures in wind tunnel operations, such as the use of safety screens, routine checks, and the presence of at least two operators during experiments.

Video Highlights

01:00 - Explanation of types of similarity and their importance in aerodynamics.
10:44 - Explanation of the concept of homologous points in geometric similarity.
19:55 - Problem-solving session to understand dynamic similarity.
25:11 - Discussion on safety issues in internal handling for high speed wind tunnels.

Key Takeaways

- Geometric similarity involves ensuring that all body dimensions in all three coordinates have the same linear scale ratio.
- Kinematic similarity requires the same length scale ratio and time scale ratio, leading to the same velocity scale ratio.
- Dynamic similarity involves the same length, time, and either force or mass scale ratio.
- Safety measures in wind tunnel operations include the use of safety screens, routine checks, and the presence of at least two operators during experiments.
- In high-speed wind tunnels, additional safety measures such as vibration sensors, safety valves, and air dryers are necessary due to the high pressures involved.