# How to design the most hydro/aerodynamic shape for a 'vehicle' that goes back and forth (using ANSYS)?

I am interested in making a very small scraper blade that moves back and forth along a submerged surface, however I need to make it as hydrodynamic as possible so I disturb the liquid as little as possible.

I understand I can model different things such as wings in ANSYS, however most of the tutorials only focus on those that have one direction of travel. I need to design the most efficient shape that will be moved in both directions in a liquid.

I know there are a lot of variables to deal with, but I need some sort of starting point on how to approach the problem. Can anyone offer any suggestions?

Edit: included a picture to explain a bit better.

• It has to have a symmetric cross-section. With that as a constraint, you only have to model it in one direction. Commented Jan 14, 2016 at 13:19
• That is true. However say I model a rain drop like shape (for a simple example), would I cut it in half and use the back end where it trails off, or the front end which is more rounded? Commented Jan 14, 2016 at 13:34
• That isn't the actual shape of a raindrop (based on the balance between internal and external pressures, it's actually shaped more like a hamburger bun, with the flat side being the leading side). However, getting back to your actual question -- you need to be a bit clearer about what you're trying to accomplish. For example, where do you expect the "scrapings" to end up? Commented Jan 14, 2016 at 16:32
• It is to be used in a 3D printer to remove UV curable resin from a glass surface before it actually cures by a projected light source shining through the glass. It takes around a second for it to cure, so I plan to have a wiper blade (about 500 micron thick) moving along the glass at 500mHz which will basically push away the liquid that would otherwise be curing to the glass, away from the surface. The goal is for the flow to be completely laminar so as not to disturb the layer where I want the resin to cure, which is about 1 mm from the glass. Commented Jan 15, 2016 at 2:05
• What? Why is the resin getting on the glass to begin with? Maybe you should draw a diagram -- it would be a lot clearer than trying to describe your printer's setup with words. Commented Jan 15, 2016 at 14:24