Dynamic Motion of the Aerodynamic Center of Pressure
Contract: Professor Garica, eg84@cornell.edu
Ornithopters are aircraft that take advantage of the same propulsion mechanism as birds, flapping wings. Ornithopter research explores the application of the unsteady aerodynamics surrounding flapping wings towards expanding flight capabilities. Many interesting and poorly understood phenomena are observed such as added inertial mass, dynamic stall, and moving center of pressure.
Classical Aerodynamics involves the study and understanding of fixed wing flight. This 'steady state' analysis involves simplifications such as small angle approximations and constant angle of attack. As such this turns out to be a greatly simplified case of the broader unsteady regime seen in ornithopters, thus classical aerodynamics cannot be used to analyze these more general cases.
The current project focuses on understanding the motion of the aerodynamic center of pressure in general flight. The center of pressure is the point along an airfoil at which the sum of all pressure forces along the airfoil act. In classical aerodynamics this is typically taken to lie at the quarter chord for simplification, which is an approximation for small angles. However, it is known that this point in general moves along the airfoil chord with changing angle of attack, but how this functions and its dependence on other parameters is not well understood.
A basic understanding of the dynamic motion of the center of pressure with changing angle of attack, as well as the effects of various parameters such as Reynolds number and chord length are the primary focus.