r-pod Airflow

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After towing my r-pod through a rainstorm this weekend and noticing the unusual patterns in the airflow, I decided to hunt around on the internet for some simulation software to see what was going on.

Using a picture of my Mazda Tribute and r-pod, I used photo editing software to create a black-on-white silhouette.  I then loaded this image into Flow Illustrator.  A few minutes later, I was rewarded with the following video:

Interesting to see how smooth the flow is over the Tribute and the front of the r-pod.  There's very little swirling at the hitch.  But look at the maelstrom at the back of the r-pod!  There's a huge airsink swirling around back there.

I wonder if a spoiler of some kind above the rear window would have a positive effect.  Are there any armchair engineers out there?

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Guests Members Profile Send Private Message Find Members Posts Add to Buddy List Guest Group	Topic: r-pod Airflow Posted: 13 Oct 2009 at 5:38pm
	After towing my r-pod through a rainstorm this weekend and noticing the unusual patterns in the airflow, I decided to hunt around on the internet for some simulation software to see what was going on. Using a picture of my Mazda Tribute and r-pod, I used photo editing software to create a black-on-white silhouette. I then loaded this image into Flow Illustrator. A few minutes later, I was rewarded with the following video: Interesting to see how smooth the flow is over the Tribute and the front of the r-pod. There's very little swirling at the hitch. But look at the maelstrom at the back of the r-pod! There's a huge airsink swirling around back there. I wonder if a spoiler of some kind above the rear window would have a positive effect. Are there any armchair engineers out there?

Guests Members Profile Send Private Message Find Members Posts Add to Buddy List Guest Group	Posted: 13 Oct 2009 at 6:27pm
	Very neat....think I'll try it out. Lou

Guests Members Profile Send Private Message Find Members Posts Add to Buddy List Guest Group	Posted: 13 Oct 2009 at 7:13pm
	VERY COOL... can you replace the tribute with a pickup open bed. I'm very curious on how the wind acts in that case. I've thought about a deflector or a camper top for the back (provided I can fit the trikes under it) that goes up at the end. Still VERY KOOL Lee

Guests Members Profile Send Private Message Find Members Posts Add to Buddy List Guest Group	Posted: 13 Oct 2009 at 10:33pm
	Excellent Post Craig .... Yet another example of r-Pod intelligence. HAPPY PODing !!!

Guests Members Profile Send Private Message Find Members Posts Add to Buddy List Guest Group	Posted: 14 Oct 2009 at 6:25am
	I cleaned-up the image a little bit. Here's the improved version: Proving my lack of engineering skills, I added a spoiler about 6' up on the rear of the pod:

techntrek Members Profile Send Private Message Find Members Posts Add to Buddy List Admin Group - pHp Joined: 29 Jul 2009 Location: MD Online Status: Offline Posts: 9059	Posted: 14 Oct 2009 at 11:05am
	Unfortunately the videos are blocked here at work - how did the airflow look with the spoiler? Did you try different size spoilers, and at different heights? Dang good idea. Would change "the look", but practicality has to come first IMO.
	Doug ~ '10 171 (2009-2015) ~ 2008 Salem ~ Pod instruction manual

Guests Members Profile Send Private Message Find Members Posts Add to Buddy List Guest Group	Posted: 14 Oct 2009 at 7:29pm
	This time, I tried to move the spoiler around. Spoiler in a low position, just over the spare. This really had no effect whatsoever. (Still image for the YouTube impared) Spoiler in a mid-position - just above the rear window. It does move the turbulence back a few feet, but I have no idea if this is a good thing. (Still image for the YouTube impared)

Guests Members Profile Send Private Message Find Members Posts Add to Buddy List Guest Group	Posted: 14 Oct 2009 at 7:48pm
	Outbound You have piqued my interest now so I would like to have more info on how you did what you did. It's been many years since I've played with finite element analysis programs but this seems much simpler. Questions 1.) how did you develop the outline of your vehicles. I want to try this with my pickup. 2.) I looked at the web site and failed to find any instructions for submitting a shape, nor establishing things like boundary conditions , air velocity, shape size, re numbers etc. Can you help me out ?

Guests Members Profile Send Private Message Find Members Posts Add to Buddy List Guest Group	Posted: 14 Oct 2009 at 9:45pm
	Sandpiper, to create the silhouette, I took a picture of my Tribute & r-pod hitched together and then loaded it into photo editing software. I used paint.NET because its relatively simple, but PhotoShop or GIMP would be the most robust choices (paint.NET and GIMP are both GPL software). I then erased the background (white) and coloured-in the foreground (black); I also drew in a "road" at the bottom of the image. In total, it took about 10 minutes to prepare the image. I then saved it as a 24-bit bitmap file. The "more info" page on Flow Illustrator goes into some depth about how to prepare the bitmap file and provides more information about the available parameters. When you're ready to run the simulation, go to Flow Illustrator's "movie maker" page, select bitmap, upload your silhouette, change the parameters as necessary, click on submit and then click on "get the movie" and wait for it to process.

Guests Members Profile Send Private Message Find Members Posts Add to Buddy List Guest Group	Posted: 14 Oct 2009 at 11:39pm
	I went back to the web site and reread the instructions. Duh !! Found the instructions to produce the bit map and there in lies the problem. I don't have my 177 yet so can't photograph the combo to produce the bit map. I'll postpone the project until I get back from picking up the *r pod*. I'll get some good photos while we camp our way through OH, TN, VA, WV, MD and PA. Thanks for your response and I'll be back to pick your brains at a later date.