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English scientific and technological development papers
introduce

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For a long time, the rafting boat has been a famous wooden Mackenzie style, which was built by Woodie Hindman or Tom Kaarhus in 1930s and 1940s in Mackenzie River country Norway. With the emergence of new materials such as aluminum and glass fiber, we have seen the evolution of design and shape, sometimes good and sometimes bad. Some drifting boat companies were founded by an enthusiastic fly fisherman who wanted to make a living by building drifting boats, but he knew little about composite materials and boat design. The movie "A River Crossing It" promoted the fly fishing of 1998 and helped those companies survive for a while.

The way to do this is to make a copy, with little modification and no consideration for beauty. As a result, there are many drifting boat owners today. For example, 15 years ago, the bottom of the ship was wrongly filled with core materials, and today they are falling apart. Potential buyers are very suspicious because they have heard the horror story.

However, there is no reason not to expect a floating platform that can let you go downstream. There is an old saying in sailing design:

"If the ship is beautiful, then she is a clipper!"

A shiny, waxed and clean drifting boat can be the pride of its owner. If a cheap wooden or fiberglass boat can take you to the same fishing place like a more beautiful boat, it is worthwhile to choose a high-quality boat in the long run. But quality is time, time is money, and sometimes the available budget size leaves us no choice.

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design

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The main difference between a drifting boat and other boats is that the drifting boat is going in the wrong direction. We really don't need a hull designed for speed, because ships travel at the speed of water. The only time we need speed is when we want to escape from danger or go upstream. In an emergency, a light ship is more important than a complicated hull design, but a light ship with a wrong stern design will also be unfavorable in the water.

Size:

As Archimedes principle says, the displacement of a ship will determine the draft of the ship, so the size and weight are very important.

Length:

There are at least two different ways to measure drifting boats: some measure the centerline from the bow to the stern, which is meaningful and is called the total length of LOA. Others measure it along the side of the ship, which is totally meaningless. I call it "self" complex.

Anyway, the total length of a ship doesn't make much sense; We should talk more about the length of the waterline, LWL. In ship design, the longer the LWL, the faster the ship. We really don't need a drifting ship, because maneuverability is the most precious quality. In most cases, we may cut off an unnecessary foot or two at both ends of most drifting boats to keep the same floor space, but save weight and limit wind resistance. Try to imagine that when Chinese people carry goods, you have two five-gallon buckets on your shoulders, and a 2x4 container is connected to the end of each bucket. If you have an 8-foot-long 2x4, you will rotate faster than if you have a 16-foot-long 2x4.

Letting the former fisherman sit at the stern 17 feet away is not helpful for maneuverability. The worst case is to put the back seat in a dry warehouse on the beam. In most cases, the seat is placed on a swivel, but the movement is limited to a few degrees on each side, so the swivel is just to increase the weight.

If the weight is properly placed, the ship will spin on a dime. It is also a good thing for the fishermen in front to see what is happening underwater in front of the ship instead of looking at the bow of the Titanic.

Width:

The drifting boat went the wrong way, unlike other boats. We need a small back end as the front end, and under any circumstances, there is absolutely no water. This means that at least three people are on the boat, the anchor is hanging outside, and a seat at the tail will put down the beam; Push back while paddling, not good!

We also need a wide enough bottom, so that every time someone leans against the boat to catch or release fish, we won't have to balance because we are afraid that this will be your last trip, because you will sink and you are not wearing a life jacket. The maximum width of the beam can be Bmax of the maximum width of the hull or BWL of the beam at the waterline. BWL also needs to be put in the right position; The correct location is a combination of the design itself and the options available on board. As the boat is relatively small, one or two people in front can play a great role. If you have a long front seat for two people; It is wise to put BWL in a place where the weight can be balanced.

Height:

The distance between the waterline and the camber line is called freeboard. Professional guides who spend most of their time on the river will have strong views on low freeboards and normal freeboards, and we understand this.

The low edge will help to resist the wind, but don't think it is a magical solution when it is windy. If the wind makes it difficult to go down the river, you have to help by rowing. The ship is now facing downstream. At this point, the low side will only reduce the windward area of the ship by 10% to 15%. On the other hand, the influence of wind on the ship's gunwale may increase the difficulty.

It is easier to jump in and out of the ship when the ship's side is low, especially for the elderly or when the ship is in deep water, but it is also easier to fall off the ship's side when the ship suddenly bumps. After a night at sea, I felt comfortable, but the river made me more cautious. There are many rivers in Montana, and I would never choose a low water level. For a family who occasionally travels on the river, a boat of ordinary height will be safer and more comfortable for children, with little extra weight.

Weight:

A ship becomes heavy not because of its choice, but because of the way it is built. There is no logical reason to build a heavy ship. A canoe will be easy and interesting to row, very sensitive and easy to load on a trailer. Heavier ships take longer to react and have greater impact when they hit rocks. It will dive deeper into the water and go down the river faster, but it will help a little on windy days. Pay attention to the difference between the weight shown on the description list and the actual weight of the ship, and pay attention to your back.

I use a translation website, and I am lazy.

The main difference between a drifting boat and a boat is that the drifting boat is on the wrong road. When a ship travels at the speed of water, we really don't need the hull to design for speed. When we need it, speed means that we want to escape from danger or back up the trend. In an emergency, a lighthouse ship is more important than a precise hull design, but a lighthouse ship with a wrong stern design may not be conducive to pushing water.

Size:

Because Archimedes' principle holds that the displacement of a ship will determine the draft of the ship-such measurement and weight are the key.

Length and width:

There are at least two different methods to measure a drifting ship: some are to measure the centerline from the bow to the transom, which makes sense and is called LOA whole. Others measure it along the unreasonable basic ship side, which I call the "self" complex.

The overall length and width of the ship does not mean that no matter what; We should talk about the length and width of the waterline, LWL. In the design of ships, we really don't need a longer LWL and a faster ship, because maneuverability is the most award-winning quality. In many cases, one foot or both ends of most drifting boats can be cut off, keeping the same floor space, but saving weight and limiting explosion. Try to vividly describe a bucket filled with 25 gallons of water, connected to the end of 2x4 on your shoulder, just like a China person carrying a load. If you have a 2x4 with eight legs, you will turn around quickly. For example, if you have a 2x4 with sixteen legs.

It's not helpful for mobility. There is a 17-foot fisherman sitting in the back in front, and the back is in this transom. This back seat is placed in a dry place and stored in this transom, which is a bad plot. This seat is placed on the swivel most of the time, but the movement on each side is limited by several degrees. This twist is to increase weight.

If the weight is good, the boat can turn for a dime. This is also a good thing for the fishermen in front, who can see the underwater situation instead of watching the bow Titanic on the front line of the ship.

Width:

This is the wrong way to drift. What boat? In any case, we need to be the front end and get out of the predicament clearly at the small end. That means at least three people stay in the boat and break down, and the seat at the end is placed in this transom; It is not good to pedal when paddling!

We also need the bottom to be wide enough, so we don't have to react to someone leaning against the side to grab or put a fish every time out of fear. This is your last trip, because you sank and you didn't wear a life jacket. This maximum width is called the beam, which may be the Bmax with the maximum width on the hull or the BWL of the waterline light. BWL needs and is placed in the right position; The correct position is the combination of the design itself and the choice on board. Because the boat is relatively small, one or two people can make great changes in the first line. If it is possible for you to arrange a front seat for two people; This is a wise place to place BWL, which will balance the weight.

Height:

The distance between the waterline and the pure line is called freeboard. Most of the time they spent on this river, they had a strong view on low freeboard, which is an expert guide to conventional freeboard, and we all know it.

A little headwind will help, but don't think it's a panacea when it's windy. If it's windy, it's difficult to reach the bottom of the river. You must help by rowing. The boat now faces the river. At this time, the lower side will reduce the area of the ship so as to provide only 10% to 15% wind. On the other hand, the effect of wind on the ship's gunwale may increase the difficulty.

When the ship's side is low, it is easier to jump in and out of the ship, especially for the elderly or when the ship is in deep water, but it is also easier to suddenly land on one side of the ship. I feel comfortable sailing in the offshore ocean every night, but this river is more cautious than me. There are many low rivers in Montana that I have never been to. For families who often travel on this river, boats of ordinary height are safer for children, and a little more weight will be more comfortable.

Weight:

The ship becomes heavier not because of choice, but because of this formula. There is no logical reason to build a heavy ship. Lighthouse boats are easy to row, interesting, sensitive and easy to put in trailers. Heavier ships need a long response time, when a greater impact force hits the rocks. It is deeper in the water and will drift under the river quickly, but it will help a little on windy days. Pay attention to the difference between the description list and the actual weight of the boat, and pay attention to your back.