This tiny pump-the size and composition of a computer chip-has no moving parts. It was built by University of Washington engineers using a design patented 75 years ago by the eccentric Serbian American inventor Nikola Tesla. Photo by Mike Urban, Seattle P-I photographer.
His name was Nikola Tesla.
Many people today, scientists and engineers included, have never heard of Tesla. Yet those who do know his work contend he may have had a more profound effect on the modern world than Edison, if not Einstein.
"His impact on the 20th century was phenomenal," said Martin Afromowitz, a UW professor of electrical engineering.
Most of our electrical power system-based on alternating current-was Tesla's creation. He invented fluorescent light bulbs, held the first patent on radio and in the early part of this century predicted future technologies that sound like cellular phones and the Internet. A basic unit of electromagnetic power is named for him. And that's just the beginning. Tesla's name is on more than 700 U.S. patents.
Yet many of his ideas, some half completed and some half-baked, languish from the same lack of recognition that today accompanies his name. One such idea was a pump design known - or in most cases not known - as the Tesla valve.
"I was surprised at how little application this (pump design) had had," said Fred Forster, a UW professor of mechanical engineering.
Forster, Afromowitz and their students had been struggling to build a tiny pump for use in medicine, electronics and any situation in which very small amounts of fluid must be pumped without the poorer reliability and damaging interference of moving parts.
Nothing they came up with worked until one night when Forster remembered a college course he took some 30 years ago. His professor had shown the class a Tesla pump. Tesla, Forster said, had built a gas engine pump without moving parts. The pump featured two complicated series of loops for the intake and outlet valves designed to favor flow in one direction over the other.
This "leaky valve" approach to pumping is not very efficient in terms of overall flow rate, Forster said, but it has the advantage of being simple in construction and highly reliable.
When Forster suggested the Tesla pump approach to his UW colleagues, they just stared at him. "Nobody had ever heard of it," he said
But the UW engineers, with gradate students Nigel Sharma and Ron Bardell, pursued the idea and found Tesla's 1920 patent. Then they created a variety of tiny Tesla-style pumps by etching silicon wafers in the same way computer chips are created.
The intake and outlet valves, each a series of pretzel-like loops on each side of the pump chamber, are about the width of a human hair. The central pump chamber, also silicon, is maybe 1 quarter-inch in diameter and one-tenth of a millimeter thick. A small electric charge applied hundreds of times per second to the pump chamber makes it flex, forcing the fluid to move. Because of the design of the valves, the fluid tends to move in one direction.
"It looks kind of bizarre," said Afromowitz. "We had no idea if this would work." It did, but only after the UW team made changes to adapt Tesla's design to fluid behavior at the micro level. Some $200,000 in private and public funding was made available to the UW engineering team now working to perfect this micropump.
"We expect miniaturized fluid systems to be a major breakthrough in new technologies," Forster said. If so, it's another breakthrough credited to a man once called "the greatest inventor the world has ever known."
There are a lot of theories, and conspiracy theories, that attempt to explain Tesla's lack of recognition despite his immense accomplishments. His contemporaries often regarded Tesla's ideas, inventions and behavior as bizarre. A Serb born in Croatia in 1856, he came to America in 1884 to pursue his interest in electrical engineering by first working in Edison's lab.
Tesla and Edison soon had. a major falling out based on Tesla's advocacy of alternating current. Edison had invested his efforts - and a lot of money - in direct current electricity and ridiculed Tesla's competing theories. Tesla left Edison's lab and sought other financial support for his research. "But Edison was high on the pecking order with the industrial giants of the day," said Nicholas Kosanovich, executive secretary of the Tesla Memorial Society Inc., based in Lackawanna, N.Y.
With Edison campaigning against him, Tesla had trouble getting funded. Eventually, he succeeded in convincing George Westinghouse to support him. Making a long and convoluted story short, Tesla created the AC induction motor that now represents about 80 percent of all electrical power in use today. In doing so, he made Westinghouse an industrial giant.
"Still, Tesla remains obscure," said Afromowitz, noting the inventor didn't profit much from his inventions because he usually had to sell the rights for the amount he needed to pay for his next project. "He wasn't much of a businessman, that's for sure."
As far as some of the scientific community was concerned, Tesla wasn't a regular scientist either. He tended to make dramatic demonstrations-such as creating man-made lightning or running high-voltage electricity through his body - and to make wild pronouncements. He dismissed as wrong Einstein's theory of general relativity and once claimedto have received communication from extraterrestrials. He had all sorts of strange phobias and compulsions and, as far as anyone knows, never had a romantic life.
Tesla died in 1943 a semi-recluse, in debt and perhaps even more on the fringes of the scientific establishment than when he began his fight with Edison. Because he seldom kept notes on his experiments, much of his work remains a mystery.
But as Forster and colleagues showed, it pays to remember Tesla.
"It's easy for an engineering or science student to think that the last 10 years are all that matters," Forster said.
Copyright 1996, Seattle Post-Intelligencer. Reprinted by permission.