Fluid Mechanics

• Fluid mechanics is the study of the forces acting on a body travelling through the air or water.
• Air resistance is the force that opposes the direction of motion of a body through the air.
• Drag is the force that opposes the direction of motion of a mody through water.
• There are 5 factors which affect air resistance: speed; frontal-cross sectional area; smoothness of surface; streamlining; and air density.
• Increased speed increases air resistance, however speed shouldn't be compromised to reduce air resistance.
• Decreased frontal cross-sectional area, decreases air resistance.
• Increased smoothness of surface, decreases air resistance.
• Increased streamlining, decreases air resistance.
• Streamlining includes reducing frontal cross section and wearing smooth surfaces.
• Streamlined shapes include: aerofoil and teardrop shapes.
• The higher the air density of the air, the greater the air resistance.
• Air resistance is lowest at high altitutde where air density is thin.
• Increased speed, increases drag. However, speed should not be compromised in order to decrease drag.
• Reducing frontal cross-sectional area, reduces drag.
• Reducing FCA can be done through a streamline position or having your hands together.
• Increased smoothness of surface, reduces drag.
• Smoothness can be increased through full body carbon fibre swimming suits and swimming caps.
• Increased streamlining, decreases drag.
• Streamlining can be increased through having arms extended above the head and dolphin leg kick in swimming reduces the drag underwater.
• Greater mass, reduces the effects of drag due to more momentum created.
• Increased temperature of pool, decreases density, as the particles have more energy, which reduces drag.
• The lane ropes of a pool absorb turbulence which reduces drag.
• The sides of the pool consume the overflow of the pool, which reduces drag for the swimmers.