Fluid mechanics - Assignment Example

A body in fluid during transport may be expected to experience drag or resistance due primarily to its irregular form or geometry, from which originates a form drag. If a submarine, for instance, is designed with unconventional outer surface, water pressure and velocity must likely be non-uniform at several points on the form as submarine’s movement proceeds through the flowing medium. In effect, the random pressure and motion of the water would enable itself to accelerate or decelerate, thereby creating frictional losses out of the fluid’s resistance to the object’s shape as the path of the water around the submerged vehicle is significantly altered in the process.

Form drag mostly occurs with aircrafts or airfoils over which air flows and separates so that turbulence becomes the outcome of combined packets of pressure, both high and low, leaving a wake or drag behind the plane. Studies indicate that form drag may be resolved on streamlining a body in order that separation, leading to form drag, may be prevented.             Another drag type is skin friction drag which is brought by a contact between fluid particles and the surface of the body about which it moves.

The idea is the same with the typical friction discussed in physics, where the resisting force builds along the plane of contact of the skins or surfaces interacting with each other as solids. Skin friction drag, nevertheless, involves interaction between gas molecules and a solid surface in which the drag magnitude is measured on the basis of the properties that identify the solid and the gas. With reduced skin friction drag, unfavourable turbulences may be minimized to desired levels when aerodynamic bodies are rendered smooth or frictionless by polishing to normalize pressure gradients and speed distribution of air.

To achieve this end, plane design to suit