Volume 2012, Issue 1 714627
Research Article
Open Access

Computation of the Added Masses of an Unconventional Airship

Naoufel Azouz

Corresponding Author

Naoufel Azouz

Laboratoire IBISC, Université d′Evry Val d′Essonne, 40 Rue du Pelvoux, 91025 Evry, France univ%2Devry.fr

Search for more papers by this author
Said Chaabani

Said Chaabani

Laboratoire IBISC, Université d′Evry Val d′Essonne, 40 Rue du Pelvoux, 91025 Evry, France univ%2Devry.fr

Search for more papers by this author
Jean Lerbet

Jean Lerbet

Laboratoire IBISC, Université d′Evry Val d′Essonne, 40 Rue du Pelvoux, 91025 Evry, France univ%2Devry.fr

Search for more papers by this author
Azgal Abichou

Azgal Abichou

Lab of Mathematical Engineering, Polytechnic School, 2078 La Marsa, Tunisia rnu.tn

Search for more papers by this author
First published: 14 October 2012
Citations: 13
Academic Editor: Zhiwei Gao

Abstract

This paper presents a modelling of an unmanned airship. We are studying a quadrotor flying wing. The modelling of this airship includes an aerodynamic study. A special focus is done on the computation of the added masses. Considering that the velocity potential of the air surrounding the airship obeys the Laplace′s equation, the added masses matrix will be determined by means of the velocity potential flow theory. Typically, when the shape of the careen is quite different from that of an ellipsoid, designers in preprocessing prefer to avoid complications arising from mathematical analysis of the velocity potential. They use either complete numerical studies, or geometric approximation methods, although these methods can give relatively large differences compared to experimental measurements performed on the airship at the time of its completion. We tried to develop here as far as possible the mathematical analysis of the velocity potential flow of this unconventional shape using certain assumptions. The shape of the careen is assumed to be an elliptic cone. To retrieve the velocity potential shapes, we use the spheroconal coordinates. This leads to the Lamé′s equations. The whole system of equations governing the interaction air-structure, including the boundary conditions, is solved in an analytical setting.

The full text of this article hosted at iucr.org is unavailable due to technical difficulties.