A veil is a piece of fabric, which can vary in size from a few square meters to several hundred square meters, which, thanks to wind, is used to move a vessel. Sails are used on sailboats, windsurfers, but also on land vehicles (Key West sail and snorkel). A veil is mainly characterized by its shape, weight, and (s) material (s) which it is composed.
The three angles of sails (a triangular sails) have a specific name: The head point is the angle at the top of web once hoisted it: this is where the halyard is hit. The tack denotes the angle attached tofixed point of boat: when sails is in position, the tack is on the front of boat. The clew refers to angle of sails which was struck listening (jib) or near which rose listening (mainsails)
During the development sailing ships (seventeenth century-nineteenth century) the increase in ship size has greatly increased the height of masts, and it has increased the number of square sails on each mast (we had 7 floors up) so that they remain cargables (foldable) with an acceptable number sailors. On the long downwind, captains clippers were sometimes added to outside extensions yards to wear veils called studding that allowed to win a little bit of speed. This delicate and risky operation was feared because of topmen the fall was the promise of certain death by drowning, the vessel being unable to turn around to come and look.
The compilation and publication in mid-nineteenth century by American captain Matthew Fontaine Maury of wind charts (sum of statistics from the prevailing winds by sectors) on charts has identified roads where the downwind (trade winds, winds commercial) were the most consistent and powerful as these rigs are effective. He contributed to development of so-called large "square-rigged" sailing (for the general appearance they had recalling the silhouette of a lighthouse).
When the ship goes back to wind, the wind flow along the veil creates a pressure difference between the windward side (underside) and leeward (suction). In fact, depression is formed on the upper surface, which "pulls" the ship, allowing it to go upwind. This same phenomenon applied to an airplane wing, which allows him to fly.
If the boat downwind, speed tends to reduce the apparent wind. Thus, contrary to intuition, this rate is not faster because it is not possible to go faster than the true wind. The fastest way to get to a point downwind way is then sometimes tacking in a direction slightly away from the axis of wind (broad reach), which increases the apparent wind. Downwind, the wind on sails tends to push the front of boat.
The maximum angle of deflection that can obtain is equal to angle of incidence of wind relative to axis of vessel. It is against-productive effect of sails border beyond the axis of vessel. The actual angle of deflection depends on the ability of air to follow the profile of sails. If the radius of curve is too short to follow the depression on the upper surface becomes too strong, and the air picks (tends to take the wind direction).
Ideally, therefore, a web has a curved profile, the profile being in front of axis of wind, and the back of profile in axis of vessel. The distance between the leading edge and the trailing edge should be as short as possible to reduce friction (drag), while being long enough to distribute the vacuum. Depression is much stronger that the forced air flow direction deviates from the axis of wind. We can therefore provide for a higher radius of curvature at the front of profile backwards. This results in an asymptotic optimal profile, where in hollow is located in first third of profile.
The three angles of sails (a triangular sails) have a specific name: The head point is the angle at the top of web once hoisted it: this is where the halyard is hit. The tack denotes the angle attached tofixed point of boat: when sails is in position, the tack is on the front of boat. The clew refers to angle of sails which was struck listening (jib) or near which rose listening (mainsails)
During the development sailing ships (seventeenth century-nineteenth century) the increase in ship size has greatly increased the height of masts, and it has increased the number of square sails on each mast (we had 7 floors up) so that they remain cargables (foldable) with an acceptable number sailors. On the long downwind, captains clippers were sometimes added to outside extensions yards to wear veils called studding that allowed to win a little bit of speed. This delicate and risky operation was feared because of topmen the fall was the promise of certain death by drowning, the vessel being unable to turn around to come and look.
The compilation and publication in mid-nineteenth century by American captain Matthew Fontaine Maury of wind charts (sum of statistics from the prevailing winds by sectors) on charts has identified roads where the downwind (trade winds, winds commercial) were the most consistent and powerful as these rigs are effective. He contributed to development of so-called large "square-rigged" sailing (for the general appearance they had recalling the silhouette of a lighthouse).
When the ship goes back to wind, the wind flow along the veil creates a pressure difference between the windward side (underside) and leeward (suction). In fact, depression is formed on the upper surface, which "pulls" the ship, allowing it to go upwind. This same phenomenon applied to an airplane wing, which allows him to fly.
If the boat downwind, speed tends to reduce the apparent wind. Thus, contrary to intuition, this rate is not faster because it is not possible to go faster than the true wind. The fastest way to get to a point downwind way is then sometimes tacking in a direction slightly away from the axis of wind (broad reach), which increases the apparent wind. Downwind, the wind on sails tends to push the front of boat.
The maximum angle of deflection that can obtain is equal to angle of incidence of wind relative to axis of vessel. It is against-productive effect of sails border beyond the axis of vessel. The actual angle of deflection depends on the ability of air to follow the profile of sails. If the radius of curve is too short to follow the depression on the upper surface becomes too strong, and the air picks (tends to take the wind direction).
Ideally, therefore, a web has a curved profile, the profile being in front of axis of wind, and the back of profile in axis of vessel. The distance between the leading edge and the trailing edge should be as short as possible to reduce friction (drag), while being long enough to distribute the vacuum. Depression is much stronger that the forced air flow direction deviates from the axis of wind. We can therefore provide for a higher radius of curvature at the front of profile backwards. This results in an asymptotic optimal profile, where in hollow is located in first third of profile.
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