MAX EBB — E
very year, in the depths of winter, my company sends me to a conference in some faraway city. It's always a city carefully chosen by my Professional Society to be an enticing destination venue. Every city has its attractions, and we are supposed to look forward to these allexpense-paid junkets. But the truth is that the inside of a hotel conference room looks pretty much the same as the inside of any other hotel conference room, and the only sightseeing we have time for is the shuttle ride from the airport to the hotel. Fortunately the presentations have improved over the years, what with middle school kids learning to use PowerPoint to good effect. But we still get the occasional speaker who thinks the highest and best use of projected images is to show a list of bullet points on the screen so they can be read back to the audience, substituting for the speaker's notes. We had two of these in a row, and by 3 p.m. I had had enough. I quietly slipped out of my chair, tiptoed over to the beverage table for a glass of water, and then slinked out of the hall instead of returning to my seat. Our conference was not the only game in town that weekend. In the next room over was something that looked a lot more interesting: It was a meeting of the Society of Naval Architects and Marine
Engineers, and the lecture in progress, according to the sign on the door, was "New Developments in Computational Fluid Dynamics." There was a serving table in the lobby with muffins and coffee, just what I needed. It was not clear which meeting the spread was intended for, but the lobby was deserted except for an attractive young woman in a business suit who was adding a third bran muffin to her plate.
"They say laminar flow when they really mean attached flow, and they say turbulent flow when they really mean separated flow." "You're a dead ringer for someone I sail with back in San Francisco Bay," I said, when I realized it was Lee Helm. "Although, she doesn't dress nearly as nice as you do." "Like, I clean up pretty good, huh Max?" She didn't have any trouble figuring
Two symmetrical NACA airfoil shapes, the non-laminar 0012 compared to the 661-012 laminar foil. By moving the maximum thickness aft, the flow continues to accelerate and the pressure continues to drop for a longer distance along the surface. Decreasing pressure helps to maintain laminar flow and minimize frictional resistance.
NACA 0012
661-012
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Latitude 38
• February, 2018
out what I was doing in this city far from the Bay. But why wasn't she in the lecture on fluid dynamics? "Lee, isn't this right up your alley?" "For sure, but, like, they're just talking about the usual applications for the programs. No mention of the algorithms. I was hoping they'd give us a look under the hood. It's a yawner." "My lecture too," I commiserated. "Let's go to the hotel bar. I'll buy you a carrot juice." "Deal!" she said, and we made our way toward the main lobby. But there was one other group meeting in the conference center that day. Our course took us close by the open double doors to a seminar on racing tactics and sail trim, put on by the local branch of a big international sail loft. The speaker was a recognizable name: an Olympic gold medalist and an America's Cup skipper. "This looks interesting!" said Lee, her face suddenly showing enthusiasm. I noticed that Lee and I both had the same color badges. Only the names of our respective professional societies, in a small font, determined which lecture series we had paid to attend. And, Lee was quick to point out, the badges worn by the folks in the sailing lecture were also that same color. "Worst that can happen is they'll throw us out," I shrugged as we discreetly walked in and found two chairs in the back row. "Pinching," said the speaker. "Sometimes you have to pinch for tactical reasons, if you can pinch your way out of bad air. Better than a clearing tack if you know you have a speed edge once
