Drag and Lift Force

  INTRODUCTION Fluid flow over solid bodies frequently occurs in practice, and it is responsible for numerous physical phenomena. When a fluid flows over a stationary body, a force is exerted by the fluid on the body. Similarly, when a body is moving in a stationary fluid, a force is exerted by the fluid on the body. And these are referred to as external flow. Some of the examples of the fluids flowing over stationary bodies or bodies moving in a stationary fluid are: 1.flow of air over buildings 2.the drag force acting on automobiles, power lines, trees, and underwater pipelines 3.the lift developed by airplane wings 4.flow of water over bridges Force Exerted by a flowing fluid on a stationary body A body meets some resistance when it is forced to move through a fluid, especially a liquid. This Fluid will exert a force on the body.                       ...