Wednesday, June 27, 2007

Should a fan blow in or out?

  It's very hot today, and I have a fan.  This fan has the ability for both exhaust (blowing air out the back of the fan) or intake (blowing air into the room).

  The question: what is best for cooling a room, blowing the hot air out or blowing the cool air in?

  The answer may depend on the circumstances.  If you want to cool a certain POINT in the room, then blowing the cool air at the point is best -- air is funneled to the point at high speed which produces both an influx of cold air and a wind chill.  

  But what happens if you want to cool off an entire room?  Or you want to keep a room cool while you are not there?  An air conditioner will work, but it's expensive to operate and it may be bad for the environment.

  Consider the following example.  You get home from work and it's 75 degrees outside after a hot day of 90.  The air in your room is still at 90, but the air outside is still at 75.  If there has been little circulation in the room over the course of the day, you may assume that floor is cooler than the ceiling -- after all, heat rises.  You may also assume that the room is relatively airtight and there are several other rooms of roughly the same temperature -- 90 degrees -- adjacent to the room with the fan.

  If we leave the fan on intake for the whole day, we may be blowing 90 degree air into the apartment during the course of the day at a faster rate than it would have entered during the course of the day if the fan weren't on to begin with.  Wind chill would have no effect on the air itself -- that's a human physiological reaction.  The only place which would be cool would be one area of the room where you are not (since you are at work).

  If we leave the fan on exhaust for the whole day, on the other hand, it will be difficult for the
hotter air outside to make it into the room.  It will help clear the entire room and ensure that air doesn't stay in the room long enough to get really hot.  However, how much good would that do?  If most of the air is blown out at window level (maybe a couple of feet above the ground), that air would have to be replaced by something -- and that something would likely just be the hotter air closer to the ceiling.

  If there is no fan at ALL (and the fan is out of the window), it's easier for air to leave or enter the room than it would be if the fan were in the window (and off).  After all, the fan is blocking the exit.

  So think about it.  There are lots of cases.

Sunday, June 24, 2007

Community values in a tight-knit fishing community

Many places in America have lost all sense of community, places where profit has become more important than people. Communities are being dissolved as people find themselves bereft of quality time with their peers due to unusually long work weeks. Individual cultures and traditions tend to lose their integrity as the Internet and other aspects of global culture tend to make society more homogeneous. However, there seem to be a few places where community and
compassion still survive.

I recently spent a weekend in Vinalhaven, Maine. Vinalhaven is an island fifteen (or so) miles away from Rockland, reachable only by ferry. It has about 1200 permanent residents, with the population swelling to about 4000 or so during the summer. Although this is a marked increase, it is nothing compared to tourist traps like Nantucket and Martha's Vineyard where hundreds of thousands of tourists visit over the
course of a summer.

There are several reasons tourists tend to ignore Vinalhaven. First, it is up in Maine, well past the outlet stores in Freeport. Even tourists who continue past Freeport into Acadia National Park generally bypass Rockland (most of them take I-95 up to Bangor or Augusta and then drive south to Bar Harbor; Rockland is on US-1). Second, Vinalhaven has virtually *no* touristy stores or chains. From what I saw, there were maybe *two* small tourist stores in the entire downtown area. Contrast that with at least three or four small seasonal mom and pop restaurants, a hardware store, and at most three or four inns. The only chain I saw was the post office: the United Postal Service.

Vinalhaven is first and foremost a working fishing town. Most of the people there are lobstermen (in case you are wondering what I ate, they had salmon and haddock as well). There are stores called the Fisherman's Friend and the Vinalhaven Fisherman's Co-op. Many years ago, Gloucester MA may have been this way. However, Gloucester is on the mainland and is much easier for tourists to reach -- it's only 30 miles or so from Boston and is on the Boston commuter rail). It is this isolation that has allowed the people in Vinalhaven to maintain their fishing traditions and communities in this age of globalization. The main newspaper there is Wind, published on someone's home computer. There is no cellphone reception and only one gas station (whose $3.63 price tag includes the cost of getting the gas from the mainland to the island). I don't recall seeing a single traffic light. Cars must secure their positions on the ferry month in advance as the ferry holds maybe 10 cars.

Closely knit communities like this are good for maintaining morality and culture. Allow me to describe several incidents which took place on this trip. Can you imagine them happening in Boston? Or New York? Or even Gloucester?

Upon arriving on the island, the GPS took me and my SO to a house in an unusual location. The people maintaining the hotel database for the GPS system had forgotten to put our B&B's house number in the system, so it presumably sent us to house number 0. We hung out outside the house for a while. Inside the house, people were looking out their window at us.

If you live in a big city, what would you expect would happen next?  "Get off our property!", right?

The people come out of the house with the inevitable "Can I help you"?  We explain our predicament and were surprised with their response.  They actually let us INTO their house, among several kids, to look up the B&B in the phone book.  How many of you would have the guts (or community upbringing) to do that?  The SO calls only to get a fax machine, at which
point a local in the house suggests a route we should take.

We thank them and start walking down the road.  Eventually, the people (who were driving 
our way anyway) pull up beside us and ask us if we needed a lift.  Who picks up hitchhikers 
in the cities?  I didn't think so.  We declined and kept on going.

The B&B turned out to be run by (from what we could tell) a very religious Christian family
(there were crosses all over the place, old Bibles, and such).  When the husband turned the 
TV on at some point, I expected him to be watching the Red Sox.   It turned out he was
watching some religious programming about Lilith (the legendary first wife of Adam) and
Asenath (the Egyptian wife of Joseph, with the narrator considering the question why a biblical hero would be marrying an Egyptian).  This sounds like morality you would expect from religious people.  What is even more surprising is that they left the door unlocked all the time.  They didn't even give us keys.  If someone did that in the cities someone would get robbed very quickly.

The biggest surprise of them all came when my SO lost her wallet somewhere between downtown and a seal-viewing lagoon called the Basin (a three-mile walk each way).  I explained the situation to a restaurant owner -- and was astonished when she threw us her car keys and let us borrow her car!  I drove the SO down all the way back down (which is highly unusual in that I generally do not drive on Saturday -- this was a bit of an emergency -- hence the six-mile walk earlier in the day) to take another look: it was close to sunset and we were concerned that it would be dark by the time we got there if we had gone back on foot.  She didn't find it.  The B&B owner the let the SO use the B&B owner's own computer -- on the OWNER'S ACCOUNT -- to figure out how to cancel all the credit cards and get her state ID replaced.  All in all, a rather panicky situation.

The reason she hadn't found the wallet became clear a day later.  Shortly before embarking on the six-mile walk, her wallet had fallen out near a bookstore downtown.  One of the store's employees found it, looked up her last name in the phone book, found it (her grandfather has a summer house there -- the only reason she and I knew about Vinalhaven), and left his number with the grandfather.  The message is eventually relayed to the SO en route back to Boston (once cell phone service is restored).  She thanks him and insists that she take the money (which was still in the wallet -- neither the bookseller nor another tourist had taken it!).  The bookseller refuses.

Incredible.  Who says there aren't decent people in this country anymore.