Spelling suggestions: "subject:"steadystate behaviour"" "subject:"steadystate behaviour""
1 |
Contribution to the modelling of aircraft tyre-road interactionKiébré, Rimyalegdo 10 December 2010 (has links) (PDF)
This thesis is a part of the French national project called MACAO (Modélisation Avancée de Composants Aéronautiques et Outils associés). In collaboration with Messier-Dowty company (a landing gears manufacturer), the thesis has contributed to better understand the actual literature studies in the field of aircraft tyre-road interaction modelling and therefore, to help making an optimal choice of model for a specifie application. The objectives have been to propose models for representing the tyre behaviour on the ground with respect to the aircraft run types. Physical oriented models are preferred. To complete this study, a literature survey of the previous researches in tyre modelling for steadystate responses is first carried out. Then, based on the main factors playing an important role in tyre modelling, it is proposed a classification for the physical and the semi-empirical models, which are also investigated. Based on this classification, the study requirements and the measurement data constraints, an a priori choice of suitable models are studied. A further investigation of the tyre deformation at pure lateral slip is carried out. It has allowed to physically describe the mechanism of generation of the longitudinal component of the tyre force at pure lateral slip. This force is refened as induced longitudinal force. By taking this force into consideration, it has been possible to explain why the self-aligning moment can drop to zero before the tyre gets to full sliding at pure lateral slip. Besides, the sensitivity analysis is proposed as a means for determining the parameters that have most influence on the model output and thus, are responsible for the output uncertainty.
|
2 |
Contribution to the modelling of aircraft tyre-road interaction / Contribution à la modélisation de l'interface pneu-piste du train d'atterissage des avionsKiébré, Rimyalegdo 10 December 2010 (has links)
La présente thèse est une partie du projet national français dénommé MACAO (Modélisation Avancée de Composants Aéronautiques et Outils associés). En collaboration avec Messier-Dowty (constructeur d'atterrisseurs d'avion), cette thèse contribue à une meilleure compréhension du comportement du pneu sur piste dans le domaine de l'aéronautique. L'objectif est de mettre en place des modèles capables de représenter le torseur des efforts au niveau de l'interface pneu-piste lors des différentes manœuvres de l'avion au sol en régime établi. Une priorité est accordée aux modèles dont les paramètres sont physiquement interprétables. De ce fait, un état de l'art des modèles de pneu en régime établi est d'abord réalisé. Un classement de ces modèles selon leurs motivations et limitations est aussi proposé. A l'aide de cette classification et en prenant en compte les exigences de l'étude, un choix a priori de modèles a été analysé. Les limites de ces modèles sont soulignées et une amélioration est proposée. Par ailleurs, une étude exhaustive de la déformation du pneu en situation de virage a été menée. Elle a permis de décrire la génération de la composante longitudinale de la force totale au niveau de l'interface pneu-piste. Elle est dite force longitudinale induite. Puis, en prenant en compte cette force, il a été possible d'expliquer pourquoi le moment d'auto-alignement peut repasser par zéro sans que le pneu ne soit en glissement total. Enfin, l'analyse de sensibilité est proposée comme une méthode permettant de déterminer les paramètres les plus influents de chaque modèle. Ces paramètres doivent alors être déterminés avec précision afin de réduire l'incertitude sur le modèle. / This thesis is a part of the French national project called MACAO (Modélisation Avancée de Composants Aéronautiques et Outils associés). In collaboration with Messier-Dowty company (a landing gears manufacturer), the thesis has contributed to better understand the actual literature studies in the field of aircraft tyre-road interaction modelling and therefore, to help making an optimal choice of model for a specifie application. The objectives have been to propose models for representing the tyre behaviour on the ground with respect to the aircraft run types. Physical oriented models are preferred. To complete this study, a literature survey of the previous researches in tyre modelling for steadystate responses is first carried out. Then, based on the main factors playing an important role in tyre modelling, it is proposed a classification for the physical and the semi-empirical models, which are also investigated. Based on this classification, the study requirements and the measurement data constraints, an a priori choice of suitable models are studied. A further investigation of the tyre deformation at pure lateral slip is carried out. It has allowed to physically describe the mechanism of generation of the longitudinal component of the tyre force at pure lateral slip. This force is refened as induced longitudinal force. By taking this force into consideration, it has been possible to explain why the self-aligning moment can drop to zero before the tyre gets to full sliding at pure lateral slip. Besides, the sensitivity analysis is proposed as a means for determining the parameters that have most influence on the model output and thus, are responsible for the output uncertainty.
|
Page generated in 0.0713 seconds