Thermo-mechanical finite element analysis and design of tail section for a ballistic missile

Download
2012
Güler, Togan Kemal
During the flight of missiles, depending on the flight conditions, rotation of missiles around its centerline can cause instabilities. To override this issue, missile generally is designed in 2 sections. In the missile, the rear tail section and the front section are to rotate freely by means of bearings. Tail section on which bearings are mounted is designed according to thermal loads due to flow of hot gasses through the nozzle and mechanical loads due to inertial load, interference fit and thread preload which appear during flight of missile. The purpose of this thesis is to determine the most suitable structural parameters according to the flight conditions of missile. The geometrical and load parameters which have effect on the results were determined. Finite element model is formed by using FEA software. After that, transient nonlinear thermo-mechanical analyses are performed and the most effective parameter on VM (Von-Mises) stress and force is determined. DOE (Design of Experiments) method was used to determine the most suitable values for the structural parameters. Totally 27 different configurations are studied to achieve to the most suitable values for variable set. It is observed that VM stress and force results for all configurations are within the ±%5 ranges. So this means parameters don’t affect the systems response very much. By taking manufacturing processes into consideration, configuration with the highest bearing inner/outer ring interference is taken. From the comparison of the results, the most suitable configuration is obtained after checking forces and VM stress on the bearings.

Suggestions

Aeroelastic Modelling and Testing of a Thin Laminated Composite Missile Fin/Wing
Aslan, Göktuğ; Kırımlıoğlu, Serdar; Kurtuluş, Dilek Funda (null; 2017-06-09)
Missile fins or wings exposed to different coupled aerodynamic loads during the mission or flight at subsonic and supersonic velocity profile. Aerodynamic loads varying with the angle of attack and the velocity profile may cause some structural fatigue and failure problems. In order to achieve such problems, high strength materials such as composites are required. In this work, a laminated composite missile fin was investigated in terms of the strength varying with the aerodynamic profile. The fiber orienta...
Experimental and analytical determination of friction torque of a double row roller slewing bearing
Dindar, Ahmet; Çalışkan, Mehmet; Akkök, Metin; Department of Mechanical Engineering (2015)
Friction at low speeds is accepted as the most dominant destabilizing factor in gun turrets, since precise aiming to the target is conducted at low speeds. So, the causes and mechanisms of friction in gun turrets should be investigated. The friction is mainly caused by the bearings in the rotation axes. In this thesis, investigation on the friction torque of a double row roller slewing bearing which is operated in the azimuth axis of a gun turret is performed. For this purpose, a friction measurement test s...
Varying mass missile dynamics, guidance & control
Günbatar, Yakup; Leblebicioğlu, Mehmet Kemal; Department of Electrical and Electronics Engineering (2007)
The focus of this study is to be able to control the air-to-surface missile throughout the entire flight, with emphasis on the propulsion phase to increase the impact range of the missile. A major difficulty in controlling the missile during the propulsion phase is the important change in mass of the missile. This results in sliding the center of gravity (cg) point and changing inertias. Moreover, aerodynamic coefficients and stability derivatives are not assumed to be constant at predetermined ranges; conv...
Load analysis of an aircraft using simplified aerodynamic and structural models
Ünay, Emre; Kayran, Altan; Department of Aerospace Engineering (2015)
Aircraft must be light enough to fly but also strong enough to endure the loads they experience during flight. Designing such a structure is one of the most demanding works in an aircraft design project. In order to design such a structure, accurate evaluation of loads is important. Once the loads applied to the structure are calculated precisely, then the deflections and stresses can be calculated and sizing of the structures can be performed accordingly. Therefore, in aircraft design projects, loads group...
Experimental Investigation of Optimal Gap Distance between Rotors of a Quadrotor UAV
Kaya, Dilber Derya; Kutay, Ali Türker; Tekinalp, Ozan (2017-06-09)
The effect of spacing between the rotors of a quadrotor Unmanned Aerial Vehicle (UAV) in hovering flight is investigated. Experiments are conducted to obtain a mathematical relation between the diameter of the rotor and gap distance between each rotor. Constraints such as the maximum thrust force and minimum energy consumption are imposed. Several rotors having different sizes are tested at various RPMs with a changing gap distances, and total thrust produced by four rotors is measured. The results are give...
Citation Formats
T. K. Güler, “Thermo-mechanical finite element analysis and design of tail section for a ballistic missile,” M.S. - Master of Science, Middle East Technical University, 2012.