David Wood's oral history comments on pump lab

by David S. Wood (BS 41 ME, MS 46 ME, PhD 49 ME)


From the Caltech Archives, the oral history of David S. Wood, dated May/June 1994:

Interviewer: And then she would send it out to everybody.

WOOD: So anyway, that was kind of interesting. Another part-time undergraduate student job I had for a while was in the Pump Lab. I don’t know if you remember that. It’s at the west end of Guggenheim. And that was Professor Robert Knapp’s big deal. He ran that affair. The funding and so on for that, as I understand it, was from the Metropolitan Water District of Southern California, when they were building the Colorado River Aqueduct. And so there was a lot of pumping of the water, and they were interested in getting the most efficient pumps they could. A lot of electrical energy was involved. So they had a scheme whereby the pump manufacturers, as part of the bidding process, would submit a model pump. And Knapp’s Pump Lab would then test it, to see how efficient it was. Knapp had developed some very accurate and fancy equipment for testing pumps— measuring accurately how much energy it took to run them, how much pressure. You know; all that stuff. So I worked there.

Interviewer: So this was in some sense a commercial operation?

WOOD: Well, they also took the opportunity to do a lot of research on the side. [Laughter] For example, one of the things I did as a student was take—I don’t know if you know what a centrifugal pump is. It’s got a so-called impeller inside, which is actually the thing that makes the water go. So one of my jobs was to test changes in the veins inside the impeller. One time I was busy—this is just with a file—filing off the tips of certain veins to make them a little shorter. Change them just a little bit, to see what effect that would have. So they did a lot of basic research on fluid turbomachinery. They learned, for example, that if you have an efficient pump and you run it backwards, it’s a very efficient turbine. In fact, Knapp got very nice results for pumps running under all possible conditions—all directions of rotation and pressures. So you could have positive pressure and positive flow, and negative pressure and positive—all that sort of stuff. And whether the energy is going in or coming out, depending on whether it’s a turbine or a pump. So they did a lot on that—a whole lot of stuff on that. Learned a lot. And made very efficient pumps in the end. Ninety percent of the energy got put into the water, where it’s supposed to be. And the reason the Metropolitan Water District was willing to put money into that operation, of course, was that a onepercent gain in efficiency of a pump on the Colorado River Aqueduct—that’s fifty years ago or more—it’s an awful lot of money. So that’s why they did it that way.

Interviewer: So all that pump testing was going on right here at Caltech?

WOOD: That’s right. Then after that project was over, then came from the Bureau of Reclamation a big project up in the state of Washington, on the Columbia River—the Grand Coulee Dam. The major reason for the Grand Coulee Dam up there in eastern Washington is basically to pump water out of the Columbia River up onto the high plateau up there. There’s a vast area that’s irrigated now. It’s just basically a desert—eastern Washington, from the Columbia River. It’s irrigated by water pumped out of the big lake behind Grand Coulee Dam. Those are very big pumps. Much bigger than even…

Interviewer: So those pumps were tested here also?

WOOD: Those models were tested in a similar way, right here. They had this beautiful facility for doing all that sort of thing. So that was done.

Interviewer: And you had some job there?

WOOD: Yes, undergraduate student jobs there.

Interviewer: But that was not your field of engineering?

WOOD: No, not particularly—I just worked there for a while.

Last updated 2/16/07.

Christopher E. Brennen