by Pepper White
The longer the time between the start of injection and the start of combustion (a.k.a. the ignition delay time), the longer the steep part of the graph lasts. This, of course, is obvious if you think about it, because the longer the ignition delay time is, the more stuff is mixed to easy burnability. More stuff's being easily burnable means the burning will happen faster, and the pressure will rise faster as the flames engulf the more easily burnable stuff almost all at once.
That's the proposition, and I'll be able to construct the arguments with further analysis of the existing data. But other questions about the combustion lingered.
How much swirl is good swirl? I've seen that swirl mixes the fuel well, but is there a point beyond which adding more swirl doesn't do you any more good? What is the global point of these experiments? If I were designing an engine for a bus, would the point be to minimize the pollution per mile? If so, would I reach a point where the cooling of the cylinder's gas from the swirl's flow decreases the power of the engine even though it reduces the emissions? Perhaps there's an amount of swirl that accomplishes the mixing without dumping too much of the combustion heat through the walls of the cylinder. To find answers will require more experiments and more understanding of combustion modeling. Another couple of years of research beyond the master's level. Peregrine White, Jr., Sc.D. It has a nice ring to it.
October 27
Atkinson. Dianne was on the phone in the second floor hall. "Look, Mitch, if you want that piece of software in four weeks, it's going to cost you. My people have problem sets and labs and exams and other stuff to do, y'know. And they need to sleep now and then." One of the other lines lit up.
"Can I put you on hold for a minute? Thanks.... "Hi, Steve. Say, can I get right back to you? You're three hours behind us, right? I'll call back before six o'clock your time. Ciao." Before she hung up the third line lit up. "Bill. Buddy. Yeah, it's coming along. Say, can I call you back in ten? Thanks."
"So, anyway, Mitch, my people should be able to deliver, but it's going to be at premium rates, and what with overhead and all. ... It's a deal? Great. I'll have a courier drop the contract by first thing in the morning."
After she was off the phone, I said, "Business seems to be pretty good."
"Yeah, I'm hangin' in there. Say, I'm going to an introductionto-real-estate seminar tomorrow. Care to join me?"
"Sure."
Next day on the way to the Boston Marriott:
"So how'd you get started in the software biz?" I asked.
"Well, I bought an Apple with my baby-sitting money when I was thirteen and I began to hack. You know how you hear these stories about musicians and how when they're in high school and all the cool people are working part time at the mall'n stuff and they're in their bedroom listening to records and memorizing solos and doing scales? Well, I was like that, only the computer was my instrument. Sometimes my mother and stepfather worried about my spending so much time alone in my room, I think.
"So, anyway, it was fun and I started subscribing to magazines and I answered an ad for a free-lance software person, and I just kept getting more work in high school. I kept up with my clients when I came here freshman year, and for a hack I put my resume in the placement office resume book. OK, I misrepresented my age and pretended I was a senior, but they never checked so freshman year I was flying around the country to plant trips-y'know, interviews at these companies-and they'd always make me job offers but I'd politely decline and hand them my business card and say, But if you'd like any work done on a contract basis ...' Instead of Senior House, 4 Ames St., Atkinson 202, I listed my address as 4 Ames St., Mail Stop A202. Once I show I can deliver on-time and on-budget these people don't even care where I live. I haven't even met half of my client contacts. It's all by phone and FedEx floppy disk mailers."
"Why do you want to go to a real estate seminar? Sounds like you're doing really well already."
"Taxes are killing me. I gotta shelter some income. Besides, my stepfather is a jerk. I mean, he thinks that since I'm making a few bucks he shouldn't have to pay my college expenses. And I say I shouldn't be penalized for my initiative. It'd get him where it hurts if I come back at Christmas and tell him I just bought a twenty-unit apartment building."
Johnny Venture stood at the front of the Marriott Long Wharf conference room and said, "You wanna be Riiiich?"
"Yessss!" the crowd of over two hundred said.
"You wanna be Set for Life!"
"Yessss!"
"For seven hundred and fifty dollars and two days of your time you can be well on your way to financial independence. Does anyone have any questions?"
"Yes," Dianne said. "Can we take the course with no money down and a balloon payment in five years?"
On the way back to Senior House I asked her whether she would sign up for the course.
"I think I'll sign up for it and take earplugs and a little notepad to the complimentary first morning session. As the guy's explaining depreciation I'll read the course binder and make note of any helpful hints. Then I'll go to the Sloan B-school library for some follow-up reading. I can't believe what suckers the rest of these people are."
"Oh. Right," I said. "Well, I wrote them a check when you made one of your phone calls."
October 30
Consortium meeting. Philip Hughes, the Aussie from Caterpillar, asked, "Is there any significance to the width of the lines on your graphs? Does it have to do with expected experimental error?" He was referring to my transparencies.
"It has to do with the width of my magic marker," I answered. They liked the joke and laughed. The sponsors had become almost colleagues, peers, friends.
Phil continued, "Do you suppose you could slide the transparencies so that, rather than lining up the start of combustion, you line up the arrows indicating start of injection one on top of the other?"
"Sure," I said.
Just a slightly different way of looking at something can yield significantly amplified insight. Professor Keck, a colleague of Heywood's and as much a physical chemist as a mechanical engineer, recognized the pattern immediately.
"It looks to me," he said, "as if you can separate the diesel combustion into two distinct phenomena. There is the chemically controlled nearly instantaneous combustion, where the only limit on pressure rise is the speed of the combustion reaction, which, based on the exponential branching of the chemical reactions, is very fast. And then you have the mixing controlled combustion envelope, the curve on the top. Here the rate of combustion can be no faster than the fuel and air mix to the chemical proportions necessary for combustion."
Professor Keck continued, "With your higher-temperature experiments, you have shorter ignition delays, and hence more of the combustion is mixing-controlled. In the lower-temperature cases, you have longer ignition delays, and more fuel is ready to go when combustion is initiated. But the mixing rate is close to the same in each case, so the longer ignition delay experiments instantaneously catch up with the mixing-controlled curve when combustion is finally initiated."
Thank you, Professor Keck. Thank you, Philip Hughes. You just wrote the "Conclusions" chapter of my thesis. As you raise the temperature of the engine's fuel and air, the fuel starts to burn sooner.
November 15
"They're going to fly me to Houston, Nick. Schlumberger wants me to come down for a plant trip," I told him.
"Hey, Cap'n, that's great. Congratulations. One of the students from the lab went to interview with them a couple of years ago. A real tough interview, he said. They asked him all kinds of technical questions, like how does a spahk plug work, and they even gave an electronics test in the afternoon," Nick answered.
I'd probably better brush off my notes from last summer, I thought. And I'd really better find out how a spark plug works. Here I've told the guy I'm Joe Diesel Engine on my resume, and I work in an engine lab. It wouldn't look good for me not to know how a spark plug works.
"Say, Nick, how does a spark plug work?"
> "C'mon over to the blackboard, Cap'n," he said.
"See, heeyuh yuh got the batt'ry, that's at 12 volts. An' that's connected to this transformuh heeyuh, the ignition coil. Then you got the contact breaker, that's just a switch that opens an' closes at the right time when the rotatin' cam shaft pushes it up an' down. On the secondary side of the transformuh, you got the distributor's rotor arm that makes the electric current go to the spahk plug when the piston's at the right place. Got it?"
"Uh huh."
"Good. Now when the contact breaker closes, current from the batt'ry heeyuh goes through the contact breaker back to ground. When it does that, it stahts a magnetic field in the primary side of the coil. Once the field gets big enough, the contact breaker opens up again, and pow! The field in the primary side collapses. The current soughta gets sucked into the condensor heeyuh, and makes the volts in the secondary field go way up, to 20,000, even 35,000 volts. That's enough volts to make the current jump the gap in the spahk plug, an' it lights off the fuel in the engine."
It was just like Doc Edgerton's strobe light, only a little less powerful.
"This is great, Nick," I said. "Do you mind if I make a little sketch of it?"
"Showah. Put it on a little piece a paper an' put it in your wallet. It might come in handy someday."
November 17
It was a night flight to Houston, and the airplane felt different now that I knew how jet engines worked, and I knew about statics and 0-rings and the stress on the rivets and how many times the wings could flap up and down before they fell off. But I didn't have time to take the bus.
I remembered the steep descent into Boston from Brussels. Had I changed since then? Was I the professional that Professor Mikic said they would make me? The two businessmen in the seats beside me discussed who would head up the valve division of their company after Higgins retired. The most likely candidate had a big house and a pretty wife.
November 18
There were four other interviewees, all from good schools: Princeton, Stanford, Cal Polytech, Notre Dame. Two of them looked like football players, which might give them an edge; it's rough work, working on oil rigs. I wondered whether my preppy horn-rimmed glasses and pin-striped suit would help or hurt.
The morning was a briefing session about the job. Movies of crews running core samples of the earth, drilling for tens of hours at a time while the youthful, sleep-deprived field engineer no older than I punched commands into the computer and gave orders to the Arabian men on the deck. Movies of the field engineers relaxing and chatting next to the pool on their two weeks' recuperation at the company resort in Oman. It looked exciting. Hard work, good money, set for life in five years-what a deal. I jotted a few notes in the little notebook that fit in my suit jacket pocket.
The morning was nonevaluative, except for the fact that Theunissen and the other interviewer, a British guy with a Ph.D. (maybe he feels underemployed, I jotted in my little notebook), both looked as if they were sizing us up and taking mental notes as we asked questions and tried to look enthusiastic.
"Now, what do you think the single largest source of accidents is for the field engineers?" Theunissen asked after the second movie. The danger must make it hard for them to hire people, even with the high money.
I suggested, "It looks as if there's a lot of heavy stuff on those rigs. I'd imagine occasionally something lands on someone's foot or ankle and mashes something." It seemed plausible enough, I thought. Oil rigs don't blow up every day.
The British guy jotted down a little note. Theunissen said, "Actually, it's automobile accidents; so if you're a safe driver, you should be fine."
Sure. Do you have a copy of the report that came up with that conclusion? Could I glance through it for a second?
For lunch we went to The Sagebrush. This was, after all, Houston. I rode in the front seat of the British guy's yellow Mercedes with brown leather interior and electric door locks.
"Hello, Sundance," Theunissen said to the waitress. "I'll have the usual; two Bloody Marys." Then he turned my way and said, "Go ahead and order; drink up, it's on the oil industry."
"I'll have an orange juice," I said.
His left eyebrow went up to his hairline. "What? Don't you want anything stronger?"
"I don't drink," I answered.
Stanford ordered iced tea, Princeton milk, Notre Dame ginger ale. I wondered whether it was because they didn't want to drink or whether they wanted to be sharp for the test. On the way to the car after lunch I jotted some notes on my little pad.
The test was a piece of cake, what with the couple of hours of preparing I'd done. It was all stuff from the first two weeks in the summer electronics course, plus a little stuff from the first fifteen minutes of six one eleven. Cal Polytech, a double E with straight A's, looked particularly intent on doing well on the half-hour quiz.
Theunissen and the British guy handed them back ten minutes after we were done. I had twelve out of fifteen points. Cal Polytech had eleven, the others were all below ten.
Ha. So I'm not such a dummy after all; it's just that at MIT you always feel dumb by comparison to the environment.
And now for the oral exam, the final interview with Theu nissen. I was ready for the lead-off question. He said, "Now, I suppose being a good American you own a car and being a good engineer you do your own work on it. Can you tell me how a spark plug works?"
I pulled the little sheet of paper out of my wallet. "You know, I heard that was one of your questions. Do you mind if I use notes?"
His eyebrow soared again. "Who gave that to you? Which one of the other candidates leaked that to you?"
"None of them, really," I answered. "The technician in my lab told me it was a standard interview question for you guys."
"Okay," he said incredulously. "Look. I know you're a smart kid. I know you can do the work. Do you want this job?"
I wondered whether it were the corporate interview manual talking or Theunissen himself.
"I want the money," I answered.
"You already told me that. I appreciate your honesty. But do you want the job? What would you do if you could do anything you want?"
Another loaded question. But answer honestly. That's what Dean Hooker at Hopkins told me when I was about to go to my interview for a Rhodes Scholarship (I didn't get it). Answer honestly, say the first thing that pops into your mind, and you'll stand out. Most people try to tell the interviewer what he wants to hear and a good interviewer can tell when you're doing that.
"Well, you know, I'm kind of an environmentalist, and I appreciate what you guys do-I mean I drive a car sometimes, too-but I'd really like to work on making the other end of the pipeline, the user end, more efficient. Maybe do some consulting in factories, invent some products that are more efficient."
It seemed to be more and more of him, not the interview manual. "So why don't you do that now?" he asked.
"It helps to have a nest egg. I figure I could work for you five years, see the world, and then do that."
He answered, "You know, that was my plan originally, but after five years, the pay was great and they offered me a huge bonus to move into management, so here I am. Do you have any other concerns about the job?"
"How often could I come home? My father's been ill, and I'd like to be able to see him more than once every two years before he leaves us."
Theunissen raised his eyebrow only slightly on that one. "We can get you home once a year on the company. Beyond that you're on your own."
Right. What's the round-trip airfare from Raleigh-Durham to Kuala Lumpur?
He continued, "Well, we'll probably make you an offer. Have a good flight home."
In the cab on the way to the airport, I reached into my coat pocket to make some further notes in my little pad. Uh oh. I left it on the table. They'll find it, compare the handwriting with the tests, and see my innermost thoughts and observations about them.
Sometimes the decision is not yours.
C H A P T
E R
19
No It Isn't
Swirling Waters ... (the Charles) Cool Charles wading, senses invading fresh splashed wake from clashes before ashes waist deep now, don't know how it will end. chest deep, eye deep, wish I had a friend All my battles so hard fought, All my efforts lead ... to ... nought...
November 19
Somebody'd pinned the poem on the wall across from my apartment. And I thought I'd earned my free room and board last December with the Watson incident. But nooooo; the institute environment does not relent.
I called John Dorsey. "See whether you can figure out who put it up there," he said. "Try to enlist the help of some of the other students, too."
Downstairs the gin game was going on in the hall. Eldon was one of the four players. "I don't know whether I'm going to make it through the term," he said.
Ah, a suspect. "Why not?" I asked.
"I've always wanted to be an astronaut. To be a mission specialist you need a Ph.D., not to mention being able to run a sub 2:30 marathon. But to get a Ph.D. from here I'll need more A's than B's and I'm pushing C's in two of my classes and I'm only a sophomore. If I get two C's, it'll be swing or swim," he said.
"What do you mean?" I asked him.
"You know, swing . . ." and he jumped up and caught the steam heating pipe with one arm and let the rest of himself go limp and his head fall limply forward.
"You do that really well, Eldon. I still think you should bag engineering and head to New York for some auditions."
"Wait, I'm not through," he said emphatically. "... or swim." He let go of the pipe and lay prone on the floor with his arms and legs stretched out the way they do in the East River.
Time to change the subject. "Do you think the Patriots will make it to the playoffs?"
"Who cares?" Eldon said. "What is this, national non sequitur day or something?"