16100lectre10_cg

# 16100lectre10_cg - Aerodynamic Center1 Suppose we have the...

This preview shows pages 1–3. Sign up to view the full content.

Aerodynamic Center 1 Suppose we have the forces and moments specified about some reference location for the aircraft, and we want to restate them about some new origin. ref M = Pitching moment about ref x new M = Pitching moment about new x ref x = Original reference location new x = New origin N = Normal force L for small = A Axial force D for small Assuming there is no change in the z location of the two points: () ref new ref new Mx x L M =− + Or, in coefficient form: N .. ref new new ref mL M mean ac xx CC C c   +  The Aerodynamic Center is defined as that location ac x about which the pitching moment doesn’t change with angle of attack. How do we find it? 1 Anderson 1.6 & 4.3 x z x ref x new M new M ref AA N ~ L ~ N ~ L ~

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Aerodynamic Center 16.100 2002 2 Let new ac x x = Using above: () ref ac ac ref M LM xx CC C c =− + Differential with respect to α : ref ac M M ac ref L C C C c αα  +  ∂∂  By definition: 0 ac M C = 
This is the end of the preview. Sign up to access the rest of the document.

## This note was uploaded on 11/06/2011 for the course AERO 100 taught by Professor Willcox during the Fall '03 term at MIT.

### Page1 / 5

16100lectre10_cg - Aerodynamic Center1 Suppose we have the...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online