Parametric Trend Study During Stability Analysis of a Tethered Aerostat

Abstract

The paper presents the longitudinal and lateral stability analysis of an aerostat tethered in a steady wind. The parametric trend study showing the effect of variation of different parameters on longitudinal stability boundaries of an aerostat has also been presented. In contrast with the conventional airplane, the equations of motion for the tethered aerostat included buoyancy forces, apparent mass terms and static forces resulting from the tether cable. The analysis consisted of mathematical modeling and its use to compute the stability characteristics for the longitudinal and lateral cases followed by the parametric trend study carried out by varying the dimensional, aerodynamic and other parameters of the aerostat for the longitudinal case. Graphical results show that the aerostat is stable for longitudinal as well as lateral case. The parametric trend study presented, thereafter, suggested that the judicious and feasible choice of various aerostat parameters could be utilized to design a new aerostat that can remain stable for wide range of wind velocities.