Quote:
Originally Posted by t vago
I may have made a mistake with the general shape of the cap.
A couple of nights ago, I was able to view the wake of my truck with the cap installed, in the rain. I noticed what appeared to be a couple of visible counter-rotating vortices right on either side of the back of the truck. From reading Hucho and looking at the pictures that Piwoslaw has in his album, it would appear the the inward-moving air stream at the sides of my aerocap are interacting with the air stream moving rearward on the sides of the truck. I think this is forming the vortices I'm seeing.
This is one of the pictures out of Piwoslaw's album.
I'm going to add material on the rear of my cap to try to straighten out the airflow. That should reduce the strength of the vortices in question. If I see some noticeable increase in FE due to the addition, then I may plan this idea into the version 3 aerocap. |
It's really tough working without a wind tunnel and models,or having the really sophistcated CFD programs the big-dogs have.
Models can take as many resources as full-scale structures,but if you skip the model and go directly to full-scale;if anything ends up hinky,it takes a lot to do the 'fix'.
Typically,the slower,higher pressure air alongside the bed is going to race towards the lower pressure of the faster moving air up top.The transverse flow whips up into the horizontal tornado attached to each upper transition.
Our challenge,according to Hucho is to get these two airstreams to meet at equal velocity and just merge together.No mean feat without all the big-boy toys!
t vago,I applaud your efforts.Hope you can stomach the work ahead.We'll all benefit and we'll all be indebted.Thanks mucho!