Computer aided engineering of an unmanned underwater vehicle

Download
2009
Cevheri, Necmettin
Hydrodynamic and thermal analyses performed during the conceptual design of an unmanned underwater vehicle are presented in this study. The hull shape is determined by considering alternative shapes and the dimensions are determined from the internal arrangement of components. Preliminary thermal analyses of the watertight section are performed with a commercial software called FLUENT to check the risk of over-heating due to the heat dissipation of devices. Performance of the proposed hull design is analyzed by FLUENT. Before simulations of the vehicle, validation studies are performed. Models 4159, 4158 and 4154 of Series 58 are chosen as the experimental reference. Their total resistance coefficients are compared with the results of the validations analyses. Mesh densities, turbulence models, near wall modeling approaches and inlet turbulence intensities are varied to understand their effects on the accuracy of predictions. A suitable turbulence modeling approach is chosen to analyze forward and vertical motions of the vehicle to check whether speed requirements are fulfilled. Hull configurations with and without appendages are used to observe their effects on total drag. It is observed that the proposed design satisfies speed requirements of the vehicle and no overheating is expected in the watertight section.

Suggestions

Analysis of regenerative cooling ın liquid propellant rocket engines
Boysan, Mustafa Emre; Ulaş, Abdullah; Department of Mechanical Engineering (2008)
High combustion temperatures and long operation durations require the use of cooling techniques in liquid propellant rocket engines. For high-pressure and high-thrust rocket engines, regenerative cooling is the most preferred cooling method. In regenerative cooling, a coolant flows through passages formed either by constructing the chamber liner from tubes or by milling channels in a solid liner. Traditionally, approximately square cross sectional channels have been used. However, recent studies have shown ...
Experimental investigation and modeling of dropwise condensation on a horizontal gold coated tube /
Serdar, Orhan; Yamalı, Cemil; Department of Mechanical Engineering (2004)
The phenomenon dropwise condensation on a horizontal gold coated tube is investigated by both analytical and experimental methods in this study. A computer program is prepared to calculate the dropwise condensation heat transfer rate on the horizontal gold coated tube. An experimental setup was also manufactured to measure the dropwise condensation heat transfer rate. The effects of flow rate, temperature of cooling water and also steam to wall temperature difference have been analytically investigated by u...
Experimental Investigation of Aerodynamic Interactions of Vehicles in Close Folowing and Passing Situations
Gümüşlüol, Ünsal; Çetinkaya, Tahsin Ali; Department of Mechanical Engineering (2006)
In this Thesis study, aerodynamic interactions of vehicle models in close following and passing situations were investigated expeimentally. Effect of the inter-vehicle spacing and lateral distance on drag coefficients of two close-following vehicles were observed. Two different types of vehicle models were used in order to investigate the shape effect on aerodynamic vehicle interactions. Drag froces and surface pressures of the models at each situation were measured. Two different blockage correction method...
Computer aided design and structural analysis of pressure vessels
Kandaz, Murat; Parnas, Kemal Levend; Department of Mechanical Engineering (2006)
This study is conducted for the design and analysis of pressure vessels and associated pressurized equipment using various codes and methods. A computer software is developed as the main outcome of this study, which provides a quick and comprehensive analysis by using various methods utilized in codes and standards together with theoretical and empirical methods which are widely accepted throughout the world. Pressure vessels are analyzed using ASME Boiler and Pressure Vessel Code, whereas auxiliary codes, ...
Experimental study of solid propellant combustion instability
Çekiç, Ayça; Ulaş, Abdullah; Department of Mechanical Engineering (2005)
In this study, experimental investigation of solid propellant combustion instability using an end burning T-Burner setup is performed. For this purpose, a T-Burner setup is designed, analyzed, constructed and tested with all its sub components. T-Burner setup constructed is mainly composed of a base part, a control panel and the T-Burner itself. Combustion chamber, pressure stabilization mechanism, pressurization system, measurement instruments and data acquisition systems form the T-Burner. Pressure stabil...
Citation Formats
N. Cevheri, “Computer aided engineering of an unmanned underwater vehicle,” M.S. - Master of Science, Middle East Technical University, 2009.