Timeline for What causes the lambda shape in a shockwave?
Current License: CC BY-SA 4.0
10 events
| when toggle format | what | by | license | comment | |
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| Feb 1 at 23:44 | comment | added | Wyatt | Yeah it seems like a hard thing to understand. I think I'll just research and question it until I have a basic understanding of what happens. (Enough to understand other topics in aerodynamics) | |
| Feb 1 at 23:42 | comment | added | Rob McDonald | Good luck. While I encourage you to learn about it for your own enrichment, it is a very small corner of aerodynamics that most professional aerospace engineers (myself included) don't know much about. If you are fascinated by it, then by all means, dive in. Otherwise, prioritize and stay a little more shallow and explore the breadth of aerodynamics a bit more. | |
| Feb 1 at 21:08 | comment | added | Wyatt | Ah I see. I think that will be a good thing for me to research more. (BL and shockwave interaction). Thanks for your help! | |
| Feb 1 at 21:03 | comment | added | Rob McDonald | Lambda shocks are a special case where multiple shocks combine together to form this kind of shape. It forms from shock - boundary layer interaction. | |
| Feb 1 at 20:14 | comment | added | Wyatt | Oh okay, thanks. So the flow behind a shock isn't always subsonic, got it. I'm also assuming that the shocks formed don't always take on the form of a lambda shock? | |
| Feb 1 at 19:57 | comment | added | Rob McDonald | The flow in front of a shock must be supersonic. After a shock, the flow can be subsonic or supersonic. All of the flows in the diagram above meet this requirement. Flow is from left to right. | |
| Feb 1 at 19:28 | comment | added | Wyatt | Oh I see. I thought it might have something to do with how the shock is formed. The last thing I am curious about : I thought for a shock to form the flow has to be supersonic (not an oblique shock) and the flow behind the first shock is subsonic? So how would the second one form? | |
| Feb 1 at 19:11 | comment | added | Rob McDonald | The angle of a shock depends on the upstream Mach number and the amount of turning. You can look up (google image search) an oblique shock table and it will show this relationship. This chart can be derived from basic compressible fluid equations. | |
| Feb 1 at 18:08 | comment | added | Wyatt | Ah I see, thanks. So not sure if I’m just not picking up something, but why do the shocks have the angles that they do? The first one has a backward angle, and the other one has a forward angle. | |
| Feb 1 at 6:47 | history | answered | Rob McDonald | CC BY-SA 4.0 |