Objective of the project task is numerical study of the underwater body motion near the free water surface in a limited depth water volume. The task has an innovative character due to complex consideration of phenomena that affect the hydrodynamics of the object. The manoeuverability of completely submerged bodies is similar to that of surface vessels. The main difference between them is the possibility of submerged bodies to manoeuver with all 6 degrees of freedom (6 DOF): three linear and three rotating motions. The surface ships manoeuverability usually is investigated only in the horizontal plane, i.e., longitudinal and transverse force and moment of yaw (around the vertical axis). In a submerged position manoeuverability of the object in the vertical plane of crucial importance in which the influence of the free water surface and the shallow water on controllability and in particular on the course stability is particularly significant.

Project team members

Person 2

Alexandrina Vasileva

PhD Student

Person 3

Georgi Tomov

PhD Student


Completed stages

Pic 01

Problem formulation and numerical simulations of the flow around underwater bodies

This stage includes: formulation of the task of flow around body under free surface near the bottom; selection of two suitable test cases for numerical simulations - elongated body flow and wing with symmetrical profile flow; development of models for numerical simulations and calculations.

Pic 02

Development a method for measuring the hydrodynamic load of underwater bodies

This stage includes: choosing a suitable test setup for model tests of underwater bodies, preparation of working documentation, fabrication and installation of equipment related to the modernization of existing facility and experimental verification of the performance of the system.


Validation model tests of underwater bodies by experimental data

This stage includes: Preparation of the experimental system PMM and models of elongated body and wing for the tests in BSHC basin; Model tests computing: depth, distance from the bottom, speed towing, angle of drift; Measurement of forces and moments and kinematic motion parameters.