Airflow over the Liftback's rear window

[LtNoogie]

I had some time on my hand so I stuck little pieces of yarn on the rear window of my liftback to see what the airflow was like back there. You can see there's turbulence at the bottom of the window. Maybe caused by the wiper?

I'll be installing Vortekz generators on the roof tomorrow and will make a another video to see if they made any difference.

Best viewed in high quality.

http://www.youtube.com/watch?v=8mO0NxNsv1k

[SilverBack]

I swear I saw another thread on this a while back...

Interesting vid, BTW:thumbsup:

I also can't tell if it's either the window wiper or sudden drop of the rear from the roof that's causing the turbulence. Maybe it'll all go away if you mount a spoiler?

[LtNoogie]

I talked about this in another thread and posted a picture of a sedan with the threads on it. I finally decided to do it for myself since I'll be playing with the aerodynamics.

If the Vortekz don't have any impact, I'll buy a rear spoiler.

[coheed]

Second row down 5th from the right, the yarn is stuck. :laughabove:

[Rich k]

dude, why haven't i done this, grand idea with the yarn and the video, good stuff. I'm really interested to see where this goes.

[LtNoogie]

:laugh: Wow, you're right. I had to watch the whole video again to see if the little sucker would ever break free. I'll free it tomorrow. Thanks.

[Kaotic Lazagna]

I know the VG's I installed are actually working. Before, when there was condensation on the rear window on my Vios (pre VG's), the entire window would be covered with it while driving on the highway. After I put on the VG's, I can see triangles forming while driving on the highway...so I would assume that the VG's are doing something. hehe.

[LtNoogie]

The VG's work better on your sedan because you can line them up straight across. I'm going to play with my placement due to the hatch.

[Kaotic Lazagna]

The VG's work better on your sedan because you can line them up straight across. I'm going to play with my placement due to the hatch.

True, although it's a little weird looking since the rear window has a small arch and the VG's are linear. hehe.

[LtNoogie]

I had to steal a picture from blacksandiegovitz but the hatch line curves out. The edge of the roofline is straight.

[Kaotic Lazagna]

Yeah, the LB's arch plus the sudden drop might affect the placement of the VG's.

[rstb88]

Your seat belt is dangling in the way you need to push it up into the plastic holder. I doubt the VG will actually affect airflow that much, it may calm it a bit, but it will not help with the void that the hatch has no choice but to make.

[rstb88]

Either way I'm looking forward to your results.

[Reddog99]

In order for a vortex generator to function, there needs to be sufficient airflow. As you can see from the top two rows of yarn in the video, there isn't much flow there. I drive a lot of dirt roads, and I can verify that a lot of dust accumulates on the rear window, and fast runs down the freeway don't blow much off. I don't think any vortex generator will do much...

[cali yaris]

Now we should try this with the spoiler and see if there is less airflow down the window with that.

[LtNoogie]

Ok, here's a video of the airflow after the installation of the Vortekz generators:

http://www.youtube.com/watch?v=0D_c6CayIT4

For reference, here's before:

http://www.youtube.com/watch?v=8mO0NxNsv1k

Watch in high quality.

Here are some pictures of the Vortekz. I misplaced the 3M 2-sided tape inserts so I'm using the next best thing for now...blue painter's tape. You can definitely see that the top row of yarn is flying around differently now. So what does that prove overall? Who knows. They look cool so I'll leave them on once I find the 2-sided adhesive tracks.

http://i426.photobucket.com/albums/pp346/LtNoogie/IMGP0824.jpg

http://i426.photobucket.com/albums/pp346/LtNoogie/IMGP0825.jpg

http://i426.photobucket.com/albums/pp346/LtNoogie/IMGP0828.jpg

[Kaotic Lazagna]

Looks much calmer now. Is it just me, or is the VG nearest in the first pic slightly over the edge?

I like how you paint-matched them too.

[LtNoogie]

Good eye. The leftmost VG is just slightly over the edge. I'll move it forward when I mount them permanently. They cannot go much further forward because when I open the hatch, they almost push against the rear of the roof.

I think the air across the back is smoother too. And they look pretty sharp.

[Saggio]

Airflow looks MORE all over the place with the VG's installed. I wanna see this done with an RS or USDM OEM spoiler mounted.