A one-way water valve with no moving parts invented over 100 | Tech Updates and News
A one-way water valve with no moving parts invented over 100 years ago by Nikola Tesla could be adapted to pump fluids around motors using otherwise wasted energy.
Tesla patented his “valvular conduit” in 1920. It is essentially a pipe with an intricate internal design that forces fluid moving in one direction to loop back on itself at various points along its length. When water flows into the mouths of the loops, it becomes turbulent and slows down, halting the flow. But if you run water in the other direction, it doesn’t enter the loops and flows freely.
Leif Ristroph at New York University and his colleagues built a 30-centimetre-long version of the valve, following Tesla’s original plan, and measured the flow in both directions at a variety of pressures.
Although Tesla claimed in his patent that the valve could make water flow 200 times slower in one direction than the other, the researchers found that their version only made it two times slower. “He was a very imaginative guy,” says Ristroph. “It’s a little unclear whether he actually made and tested it. I suspect so, but there’s no documentation of that.”
Although the effect was much lower than Tesla claimed, the valve is still a useful design, says Ristroph, especially as it has no moving parts so could be maintenance-free.
“It has been known about and has been used in some applications, or at least proposed for use. But no one had ever really done the thorough hydrodynamics work on it to figure out how it works, how well it works,” says Ristroph.
