Sail

The utility model relates to the technical field of sails, in particular to a sail which comprises a sail body, the sail body is in a curved surface shape, the sail body is twisted towards one side of the sail body from top to bottom, the horizontal cross section of the sail body is in a wing shape or a U shape, and when the horizontal cross section of the sail body is in a U shape, the sail body is in a U shape. The thickness of the two side walls of the U shape is smaller than the thickness of the connecting arm connected between the two side walls, the sail sections at different heights can obtain the optimal airflow attack angle, the boosting effect of the sail sections at different heights in the vertical direction is fully achieved, efficient boosting of the whole sail under the wind coming condition is achieved, and the sail has the advantages of being simple in structure and convenient to use. And the output power and fuel consumption of a ship propulsion main engine are reduced, greenhouse gas emissi