OVERVIEW

Computational Fluid Dynamics (CFD) is becoming more and more attractive in the marine industry, as a complementary tool to usual model and full scale measurements. A deep knowledge of the theoretical basis of each approach, their limitations, the applicability fields and the quality of the results is, consequently, fundamentaal for the successfull application of these approaches to the design and analysis problems typical of naval architecture.

AIMS AND CONTENT

LEARNING OUTCOMES

Introduction to the approaches (theoretical basis and numerical implementations) for the numerical solution of the typical problems related to the Naval Architecture (propulsion, hull resistance, cavitation). Development of simple numerical tools and application of high-fidelity solvers (RANSE) in order to identify their applicability to design problems, possible limitations and fields of applicability.

AIMS AND LEARNING OUTCOMES

The aim of the course is to provide a theoretical and practical knowledge of the principal aspects related to the application of numerical techniques to hydrodynamic (and in particular to Naval Architecture) in order to:

• Have an overview of the most important approaches (and of their limitations), like BEM and RANSE, for the solution of problems of interest in Naval Architecture (Propeller performance, Free surafce flows, Hull resistance), with a brief introduction on their fundamental equations and the most suitable discretization strategies;
• Understand the application limits of the available numerical approaches and critically be able to discuss them;

By:

• Development of simple numerical codes based on the potential flow theories illustrated during the course (2D potential flow solvers for thin profile theory, BEM using Hess&Smith for hydrofoil, 3D lifting line) using Matlab (or C++, FORTRAN, depending on the experience of the students);
• Training with StarCCM+ for the solution of the viscous flow using the RANSE approximation of the continuity and momentum equations around geometries of interest (simple 2D problems, like hydrofoils, 3D wings and rudders, Propellers, multiphase fluids)

In order to:

• Understand the main hydrodynamic phenomena that determine the performance of hydrodynamic bodies (rudders, fins, propellers, hulls) relevant to naval engineering;

• Critically assess the applicability limits of various numerical methods dedicated to computational hydrodynamics;

• Apply the appropriate computational fluid dynamics (CFD) tools;

• Develop simple numerical analysis models.

TEACHING METHODS

Oral lessons (abt. 35 hours) and computer lab (25-30 hours).

Students with valid certifications for Specific Learning Disorders (SLDs), disabilities or other educational needs are invited to contact the teacher and the School's contact person for disability at the beginning of teaching to agree on possible teaching arrangements that, while respecting the teaching objectives, take into account individual learning patterns. Contacts of the School's disability contact person can be found at the following link Comitato di Ateneo per l’inclusione delle studentesse e degli studenti con disabilità o con DSA | UniGe | Università di Genova

SYLLABUS/CONTENT

• Brief overview of Fluid Mechanics Equations;
• Potential flow approaches, theoretical basis and numerical implementation using Matlab, or FORTRAN or C++ of:
  • Thin profile theory
  • 3D Lifting line
  • 3D Lifting Surface
  • BEM usig Hess & Smith for 2d Hydrofoils
• RANSE approaches, including the relevant theory, discretization apporaches, meshes, single and multiphase problems by training with StarCCM+ for the solution of:
  • Hydrofoil in steady and unsteady conditions; Stall;
  • von Karman Vortexes;
  • Mesh motions
  • Free Surface Flows (2D roll motion, free fall of a wedge on a free surface, hydrofoil under the free surface)
  • 3D wings and rudders, tip vortex
  • Propellers in steady flow

RECOMMENDED READING/BIBLIOGRAPHY

J. Katz & A. Plotkin, "Low Speed Aerodynamics - From wing theory to panel method", McGraw-Hill

J.H. Ferziger & M. Peric, "Computational Methods for Fluid Dynamics", Springer

Siemens PLC "StarCCM+ users' guide" (software licence distributed durig classes)

TEACHERS AND EXAM BOARD

LESSONS

LESSONS START

https://corsi.unige.it/8738/p/studenti-orario

EXAMS

EXAM DESCRIPTION

The exam consists of an oral assessment (regardless of the dates indicated in the calendar, to be scheduled based on mutual availability), primarily based on a presentation of the project work (development of a computational code for a specific fluid dynamics problem, application of the RANSE solver, analysis and discussion of the results) carried out by the student during the semester. The discussion of the project and the achieved results is followed by an in-depth examination of the models/tools used for the (theoretical and numerical) solution of the assigned problem.

ASSESSMENT METHODS

The exam, structured as an oral interview and discussion of the project work, aims to assess the student’s ability to critically analyze the results and methodologies adopted (including limitations, potential developments, and alternative implementations). Mastery of the topics covered in class, the ability to contextualize them within the assigned project, critical discussion of the results in light of the methodologies used, understanding of concepts and issues, along with the ability to argue effectively, are key elements in the evaluation of the work carried out during the semester and the oral exam. The student’s assessment is based on their ability to independently describe the topics presented in class and developed during the exercises with coherence, appropriate terminology, and clarity.

FURTHER INFORMATION

For other/additional information not included/addressed, please ask the professor