• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 1
  • Tagged with
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Generation of a full-envelope hydrodynamic database for hydrobatic AUVs : Combining numerical, semi-empirical methods to calculate AUV hydrodynamic coefficients

Miao, Tianlei January 2019 (has links)
The next generation of Autonomous Underwater Vehicles (AUV) can impact our observation of the world. The flight simulation and full-envelope hydrodynamics modeling can improve the performance of AUVs in terms of control, navigation and positioning. In order to achieve agile maneuverability, a more accurate database of full-envelope hydrodynamic coefficients is supposed to be generated. Two semi-empirical methods, Jorgensen and DATCOM, and two numerical method, Computational Fluid Dynamics (CFD) and XFLR5 are used to push the boundaries of hydrodynamic coefficients: lift, drag and moment coefficients for flight-style AUVs at the Swedish Maritime Robotics Center (SMaRC). A comparison of different approaches and tools, and an analysis of the most appropriate approaches for different regions of a defined maneuver has been conducted in this thesis. A data confidence level was proposed as a way to estimate the accuracy of the data and a structured database was built in terms of data confidence level. Different components of the AUV such as the hull body and wings were analyzed separately. The new database is input to a 3DOF Simulink model and the 6DOF SMaRC hydrobatics simulator for flight dynamics simulations. Simulations show that the new database has a good applicability.

Page generated in 0.0443 seconds