Analysis of a kite anemometer

Equations of motion for a rigid, tailless kite and tether system are derived from free body diagrams. A direct, analytical solution of these equations provides tether tension in a steady wind. Numerical solutions of linearized equations of motion provide the kite tether tension in a transient, turbulent wind field. A similar analysis is applied to a kite-tail-tether system. The results of these analyses show that line tension at the ground anchor is within a few percent of tether tension at the kite. Wind shear does not significantly affect line tension. Thus the tethered kite anemometer can measure height-dependent wind fields based on steady-state, uniform wind calibrations. Unsteady winds also have an insignificant effect on the tether if gust amplitude and frequency are such that tether accelerations are below 9.8m/s(2). In a variable wind, tether tension is in phase with wind variations. Tension amplitude is dependent on the magnitude and frequency of wind variations.