Chapter 770 Sail
The heavy ship was dragged across the beach, and the wooden planks and gravel made a slight friction sound, breaking out small grains of sand.
White foam washed the shore and touched the white wooden hull, wetting it to a dark gray.
The resistance became less and less, and Bifang pushed the canoe into the sea completely with all his strength.
Two small boats connected together floated on the sea, pushing away the incoming waves, and the sea water poured out through the gap between the connecting platforms.
Seagulls fly on the skyline, and the waves are sparkling.
On the mast, thin ropes fluttered in the wind, twisting like mad snakes.
Today is a rare windy day.
As an island, it is naturally impossible for a temperature difference between the continent and the ocean to form, and for sea and land breezes to occur. This is just a coincidence.
The vast sea breeze rushes towards the land from the vast sea surface of thousands of kilometers, mighty and powerful.
As a canoe with a sail, it is not suitable for going out to sea, but Bifang used a Latin triangular sail. As a professional survival expert, he should use the triangular sail to sail against the wind!
"Are you ready?"
The audience responded enthusiastically. The familiar opening remarks had already livened up the entire venue. Without much action, a large number of barrages of comments flooded the live broadcast room.
【Ready! 】
[Yes, Captain Bifang.]
[Too quiet! How can you drive a warship with such a quiet voice? ]
Everyone looked at Bifang expectantly.
Tourists on the shore stood on tiptoe and held up their mobile phones to take pictures.
The audience sent gifts and comments.
Just when everyone thought the fun was about to begin, Bifang suddenly grinned and asked, "Who lives in the big pineapple in the deep sea?"
Everyone was stunned, not understanding why Bifang suddenly said such a thing.
But those who reacted quickly immediately responded with barrage of comments.
【It's SpongeBob! 】
[No, it's Captain Bifang! ]
[Dirty～～～]
Too many elements
[The next sentence is Fang Fang and Huang Huang can stretch and shrink freely! ]
The sudden meme added a touch of relaxation and joy to the tense atmosphere.
"Fang Fang Huang Huang can stretch and retract freely!"
【SpongeBob! 】
"If exploring is what you want."
【SpongeBob! 】
Bifang jumped onto the platform by stepping on the sea water and knocked on the hull with a wooden stick, making a unique bang-bang sound, like some kind of unique prelude.
"Then knock on the deck to make way for the big fish!"
The canoe rose and fell with the waves. Bifang stretched out his right arm, wrapped the hemp rope around it several times, and pulled it diagonally from top to bottom.
The hemp rope rubbed against the wooden pole rapidly, making a violent twitching sound.
“Crash!”
The pure white canvas was pulled up, and the strong wind instantly inflated the sail.
Bifang jumped onto the aircraft carrier holding the rope, adjusted the direction of the sail, and the entire triangular sail cut through the strong wind like a sharp blade.
The sudden weight caused the aircraft carrier to sink suddenly, but then bounced up suddenly with the support of the Viking and buoyancy, bringing up a large amount of sea water.
The smooth arms pull the textured rope, and the cold sea water splashes on the naked chest, which is a refreshing and free experience.
The triangular sail that cuts through the strong wind bulges at the front and deflates at the back, like an airplane wing. The huge lift acts on the canoe, pushing away the sea water and accelerating its progress.
“Go!”
"come on!"
“Easter Island will record this moment!”
There were people on the shore shouting, cheering, and screaming. The voices were loud, but they were infinitely stretched and distant.
The canoe was moving faster and faster, and the cheers behind us were getting smaller and smaller. When we looked back, they were barely noticeable.
Bifang laughed heartily and kept adjusting the sails, confirming the wind direction according to the direction of the ropes on the mast, always keeping the sailboat in the position with the greatest lift or thrust.
This is also the place that tests the driver's skills the most.
【Go, go, go! 】
[I used to watch the sailing championships and thought they were so damn cool, so I always had a dream, which was to sail across the lakes and oceans, but I never had the chance. Watching the live broadcast here can be regarded as a dream come true in disguise (crying)]
[By the way, why can we move forward even against the wind...]
[The previous one, it seems that I didn’t learn physics well. It’s obvious that this is the basic knowledge of quantum mechanics]
[I have little education, please don’t lie to me]
[15cm (excluding the head) is given to the anchor as a yacht*1. ——Fang Shen is so handsome! 】
[The bearded little milk bottle presents this to the anchor Big Bone *66 - these damn pectoral muscles, damn biceps, damn shark gills, lick them like crazy]
"This is very simple." After simply maintaining stability, Bifang fixed the halyard and tied it to the mast. He took the time to look at the bullet screen. "There are roughly two major ways for a sail to gain force, namely forward blowing and tangential blowing."
"Forward blowing is easy to understand . It is to capture the impact of the wind directly on the back of the sail and then push the boat forward. This is Newton's action and reaction."
"When sailing downwind, the sail surface is in a 'stretched' shape, which is the best working condition. The larger the sail area, the greater the wind thrust. Therefore, the square sail, including the square sail and the triangular sail, are very suitable for sailing downwind."
"The principle is simple: Newton's third law of action and reaction."
"When the wind from the side is reflected from the back of the sail, it will also generate thrust. As long as the direction is from the back, no matter how it is tilted, it can provide a certain amount of thrust. This is the tangential force generated, pulling the boat forward. Anyone who has studied force analysis should know this."
"But using headwind is more complicated, using the Coanda effect and the Bernoulli effect."
[Sorry, I only graduated from elementary school, what are these two? ]
[Luckily I studied fluid mechanics in college, otherwise I wouldn’t really understand it (dog head)]
【Physics Master Fang, online】
[Teacher Fang’s class has started. My child is not good at physics. It’s probably because he doesn’t watch the live broadcast enough. He just needs a beating.]
"According to Coanda's theorem, when a gas or liquid enters tangentially to this surface, it will flow along a convex surface. Whereas laminar flow along a curved surface will continue to adhere to the same curved surface."
"This deviation from the straight line of airflow will generate a force on the sail surface along the curved surface, resulting in a force perpendicular to the sail. This force is mainly used by modern wing sails."
After fixing the tether, Bifang sat in the Viking.
"According to the Bernoulli effect, when the wind blows tangentially across the two sides of the sail, the airflow on the front side passes through a curved surface and then recombines with the airflow on the rear side, flowing backward as a chord flow. Then the fast airflow on the convex front side will reduce its internal pressure relative to the other side."
"The Bernoulli effect is a topic in fluid mechanics, and is usually only taught in university courses, so you may not be familiar with it. But its case should be relatively clear to everyone, that is, the pressure difference produces 'lift' perpendicular to the sail - that is, the working method of the wings of an airplane."
[I know this, I took physics in junior high school (covering my face)]
【Finally saw familiar content】
[In short, you can fly even against the wind, right?]
"It's not that exaggerated. Basically, sideways headwind is OK, but headwind is not OK in theory. However, a complete headwind is not common in actual sailing."
