Traction kite testing and aerodynamics
Thesis DisciplineMechanical Engineering
Degree GrantorUniversity of Canterbury
Degree NameDoctor of Philosophy
A Traction kite is a controllable high performance kite used to pull other objects in a desired direction. In recent years Traction kites have been used for Kite Surfing and Kite Buggying, generating significant sales revenue. In conjunction with Peter Lynn Kites Ltd, this aim of this project was to develop testing methods to determine Traction kite performance. An additional aim was to lay the fundamental groundwork of kite theory to enable further research on kites. The original testing method used a car-based test rig, in which kites were flown from the roof of the car while driving down a beach. By measuring each kite's line angle and tension under various conditions, the performance of each kite could be determined. Despite extensive development this method was only moderately successful. In particular, the tangent relationship between a kite's line angle and Lift to Drag ratio caused large experimental errors. In light of the difficulties, a circular testing method was developed for testing Traction kites. It was found that if a kite was flown indoors, in a horizontal circle around the flyer, the performance of the kite was related to the geometry of the test setup. This method was far less sensitive to measurement error and provided very good kite performance results. Unfortunately, this method is limited by the size of the required test site. Investigations of kite theory determined that the stable flying location of a kite could be predicted and this led to other key flight characteristics. In particular, the structural requirements of a kite can be addressed and the initial turning properties of a kite can be determined.