Determination of static and dynamic stability characteristics of a sailplane based on CFD analysis. Part 1 static stability

Abstract

The purpose of this research is to evaluate static and dynamic stability characteristics of a sailplane in flight. In the current paper - part 1, the static stability is studied. Conventional ways of determining static stability characteristics of an airplane are based on semi-analytical models comprised of equations and formulas, which are not easily applicable in the design case of an aircraft type such as that of a sailplane, due to the relatively high aspect ratio, lack of thrust force, weight requirements and complex geometry. Instead a new method using CFD analysis is developed. A sequence of numerical analyses is executed in Ansys - Fluent. Steady state cases are used. Exact numerical results are obtained for all three longitudinal, directional and lateral stabilities. All of the data obtained from the CFD studies is used in the design process of a sailplane. All results from the proposed method are confirmed by analysing existing aircraft of the same type and mission.