Skip to main content

DRAG

 

                                                                               Drag

When an aircraft or any other body moves in atmosphere it experiences air resistance which retards its forward motion. This force is called drag. Drag occurs when an aircraft or any other object moves in air and it depends on the shape of the flying object.  Aircrafts and other flying objects are designed in such a manner to reduce the drag, which increases the efficiency of the aircraft.




Drag is experienced parallel to relative airflow. Drag is directly balanced by thrust produced by a propeller or an engine. Amount of thrust required to balance the drag depends of amount of drag, more thrust is required to balance a greater drag force produced.

If the drag produced by an aircraft is low then the aircraft consumes less fuel and operating costs are also low. The total drag acting on an aircraft includes

  • Profile drag                                       
  • Induced drag
  • Interference drag

Profile drag is further divided into

  • Form drag
  • Skin friction drag 



Labels:

Comments

Post a Comment

Popular posts from this blog

Form Drag

                                                                       Form Drag Form drag is experienced in the surface of the aircraft when the streamlined airflow separates and becomes turbulent. To experiment form drag keep a flat plate on the streamlined airflow, now the pressure before the plate is atmospheric and the pressure after it is below the atmospheric which results in sucking effect behind the plate and vortices are formed. It is mandatory to delay the separation point of airflow and this is achieved by altering the shape or streamline of the given object. When the airflow changes its direction rapidly form drag experienced is higher. A fairing is fitted around the fixed undercarriage leg to reduce form drag to consi...
1 comment
Read more

AIRFOIL TERMINOLOGY

                       Air foil Terminology What is an airfoil? How an air foil is described in modern science, what are the parameters that determines its shape? An Air foil is primary building block of an aircraft which has two edges namely leading edge and trailing edge, the straight line connecting the leading and trailing edge of the air foil is called as chord line. The line which is drawn equidistant from the upper and lower surfaces of the air foil and connecting the leading and trailing edge is called as mean camber line.The distance between the leading and trailing edge is called chord of an air foil.   The maximum distance between the mean camber line and chord line is referred as maximum camber. This is one of the variables that determine the aerodynamic characteristics of the wings. Maximum thickness to chord ratio is expressed in terms of percentage. For subsonic wings the ratio is normally 12-14%...
Post a Comment
Read more

Angle of Induced downwash

                                                    Angle of Induced downwash Downwash generated through vortex deflects the airflow from horizontal through an angle called as the angle of induced Downwash. This effect not only occurs behind the wing but also impacts the airflow approaching the wing by deflecting in upward from the horizontal through the same angle ( ʠ ). The resulting airflow is called effective relative airflow and the angle between effective relative airflow and the horizontal is called Ineffective angle of attack. The resultant lift force which acts perpendicular to the relative airflow is also deflected rear ward through the same angle ( ʠ i ). The angle of attack producing this Lift force is called effective angle of attack ( ʠ e ) which is the angle between chord line and effective relative airflow. A portion...
Post a Comment
Read more