ABSTRACT
Aerodynamics principles explain the properties and functions of the airflow around an aircraft. This chapter focuses on the aerodynamic principles when airspeed is relatively low – in subsonic region. There are a few of fundamental principles of physics used in aerodynamics: conservation of mass; Newton’s laws of motion; conservation of energy; and ideal gas law. From these principles, the chapter shows how to derive the following basic and often-used equations: Continuity equation, Bernoulli’s equation, and Energy equation (of fluid flow). It adopts the Eulerian viewpoint, which is to observe a fluid particle along a streamline at a particular moment of time, to study the pattern/behavior of fluid flow. Streamlines do not intercept. the speed of a fluid flow is relatively high when the streamlines are drawn closer to each other. The airspeed of an aircraft is commonly obtained through a Pitot tube. The output of the Pitot tube is the pressure difference, i.e. the dynamic pressure, measured by two channels.
