Like that? It’s an idea. I’d say the “whale-tail” on the 911 has a spoon shape too. Makes sense to me.
Mainly, I feel like I’m standing confused at a metaphorical crossroads. Julian Edgar teaches that tufts on my car’s rear glass represent true flow. aerohead and other members on this site believe that the tuft flow is actually a symptom of downwash and vortices from the C-pillars. Vman455 (who has a website that I’m now obsessed with) seems to shoot somewhere in between.
so, accordingly, I have three ideas in mind for rear windshield aero:
-create a bonneville type spoiler, to smoothen airflow. This looks to have the cleanest tuft-flow. I could use a device such as a vortex generator or a wing to channel energy into the boundary layer, according to Ford and Mitsubishi cars; but wouldn’t that just cause drag in itself? I’d have to do it properly enough to make the gain higher than the cost.
-create an add-on kammback or fastback. The one in that older “ECOfamily Civic” thread is a nice design. But that adds weight, complexity, presumably noise, etc. Would be annoying to mount it when I don’t want to screw into the body at all. I’d need plexiglas for rear vision and it would likely fog or scratch….blah blah (I’ve beaten that idea to death before)
-create an artificial fastback, and capture air into a bubble, which will force air to flow over it. That’s more or less what the drawings in my last post show. I’m not sure if this is best, but it could be. According to aerohead, this needs to have zero porosity. Hm.
Vman455 makes a great point when speaking of testing:
“The air doesn’t care about what you think it should do, and you’re most likely wrong anyway.”
Yet, the people who disagree with him are also respectable, with many credentials; so I’m going to observe any ideas I have.