Expansion Waves — Lesson 4

In the previous lesson we looked at the various types of shock waves that are formed over objects traveling at supersonic speeds. One common factor for all these shock waves is that the interaction of the flow with the object leads to compression in the direction of the flow. But there can be situations where the exact opposite happens, i.e., the flow turns in such a way that it expands in the direction of the flow. Consider the cone-cylinder shown below. At the leading edge, we can see that oblique shocks are created. However, as the flow moves downstream, at the convex corner, it turns away from itself, leading to the formation of expansion waves.

In this video lesson we will discuss the physics behind these types of compression waves. Based on this physical understanding we will construct a theoretical framework that can be used for analyzing expansion waves.

Alternate video link.

Let us now look at the accompanying handout slides for this lesson.