Seeing the other tesla valve, I was pretty certain that the same principle could be extended to 3D. I came across a more symmetric, optimized design of a tesla microvalve at http://www.senlin41.org/topology-optimization-of-tesla-type-microvalve/ and traced it. The following is a trace of the optimized valve in openscad with added support to make it printable without overhang or flying parts. Parameters allow you to set the coarseness of the rotational extrusion ($fn=32 works fine for me), and the distance of the support bridges.I have not printed or tested that yet, so I suggest you start with the scad file and adapt it to your needs. The scad is divided up into the modules tube: the outer tube. Just a cylinder with matching dimensions. negative_space: everything you have to subtract from a tube to obtain a valve. (shown upside-down in the picture - in case you were wondering about printability) positive_space: all the bridges and islands within the negative space. valve: a complete valve = tube-negative spaceYou may also want to add a second set of bridges on the other side of the "bullet" for stability, and to deal with vibrations.