Experimental hydrodynamics and simulation of manoeuvring of an axisymmetric underwater vehicle (original) (raw)
Related papers
Effects of Hull Length on the Hydrodynamic Loads on a Slender Underwater Vehicle during Manoeuvres
OCEANS 2006, 2006
Williams, C. D.; Curtis, T.; Doucet, J. M.; Issac, M. T.; Azarsina, F. Contact us / Contactez nous: nparc.cisti@nrc-cnrc.gc.ca. http://nparc.cisti-icist.nrc-cnrc.gc.ca/npsi/jsp/nparc\_cp.jsp?lang=fr L'accès à ce site Web et l'utilisation de son contenu sont assujettis aux conditions présentées dans le site Web page / page Web http://nparc.cisti-icist.nrc-cnrc.gc.ca/npsi/ctrl?action=rtdoc&an=8896092&lang=en http://nparc.cisti-icist.nrc-cnrc.gc.ca/npsi/ctrl?action=rtdoc&an=8896092&lang=fr
Applied Ocean Research, 2010
Straight-ahead resistance tests and static-yaw runs up to 20°yaw angle for the axi-symmetric bare hull configurations of the ''Phoenix'' underwater vehicle that were performed in the 90 m towing tank at the Institute for Ocean Technology, National Research Council, Canada, provided empirical formulae for the drag force, lift force and turning moment that are exerted on such axi-symmetric torpedo-shaped hull forms. The empirical formulae were then embedded in a numerical code to simulate the constant-depth planar manoeuvres of the MUN Explorer autonomous underwater vehicle (AUV). The simulation model was first calibrated using the sea-trial data, and then was used to study the turning manoeuvres and to compare the simulation results with those from theoretical formulae based on the linearized equations of motion. The simulation results show non-linear changes in the hydrodynamic coefficients as the turning manoeuvre becomes tighter.
OCEANS 2008, 2008
Modelling the hydrodynamic sway force exerted on the bare-hull of an Axi-symmetric Underwater Vehicle in lateral acceleration manoeuvres Azarsina, F.; Williams, C. D.; Issac, M. Contact us / Contactez nous: nparc.cisti@nrc-cnrc.gc.ca. http://nparc.cisti-icist.nrc-cnrc.gc.ca/npsi/jsp/nparc\_cp.jsp?lang=fr L'accès à ce site Web et l'utilisation de son contenu sont assujettis aux conditions présentées dans le site Web page / page Web http://nparc.cisti-icist.nrc-cnrc.gc.ca/npsi/ctrl?action=rtdoc&an=8895157&lang=en http://nparc.cisti-icist.nrc-cnrc.gc.ca/npsi/ctrl?action=rtdoc&an=8895157&lang=fr
Optimization and Analysis of the Hydrodynamic Coefficients for an Underwater Vehicle (UV)
2020
The present paper achieves a numerical study to improve the performance of an optimal hull of an underwater vehicle using iso-geometrics equations of the model SUBMARIN hull and ANSYS CFX software package for Computational Fluid Dynamics. The study is twofold. First, evaluate and calibrate the CFD model for the underwater vehicle, second, the previous concept are transferred in order to obtain numerical results for AUV optimization and analysis. Optimization results for compliance criterions which allow controlling the shape such as drag coefficient is presented. The numerical results show a good agreement with those of the experimental one. Thus, an analysis of the coefficients of the added masses coefficients and the damping force are carried to help to understand the AUV acceleration behavior at sea. Key-Words: Underwater vehicle hydrodynamic added mass optimization CFD boundary conditions
A Physics-Based Means of Computing the Flow Around a Maneuvering Underwater Vehicle
have developed a physics-based method that will lead to a means of accurately predicting the forces and moments acting on a maneuvering, self-propelled, appended, underwater vehicle and the resulting vehicle motion. This methodology has been developed in order to supplement and, eventually, replace the traditional correlation-based means of "predicting" the maneuvering characteristics of a submerged vehicle. One primary difference exists between this new physics-based method and traditional correlation-based methods. While the traditional methods use empirical correlations from model-scale experiments to determine the hydrodynamic forces and moments acting on a vehicle during a manevuer, this new method numerically solves for the fluid dynamics using the three-dimensional, time-dependent Reynolds-averaged Navier-Stokes equations on time-dependent curvilinear coordinates. Considering that large-scale simulations of a maneuvering vehicle at high Reynolds number will require large amounts of floating-point arithmetic and considerable storage capacity, the research team also investigated the use of high-performance parallel computing for making these types of large computations. In addition, while the hagpiinp cndp used 14. SUBJECT TERMS Vehicle, Maneuvering, Computational Fluid Dynamics 17. SEOURTTY CLASSIFICATION OP REPORT
A theoretical methodology to determine the open-loop directional stability of a near-surface underwater vehicle is presented. It involves a solution of coupled sway and yaw equations of motion in a manner similar to that carried out for surface ships. The stability derivatives are obtained numerically through simulation of motions corresponding to planar motion mechanism (PMM) model tests. For the numerical simulation, a boundary-integral method based on the mixed Lagrangian-Eulerian formulation is developed. The free-surface effect on the vehicle stability is determined by comparing the results with that obtained for vehicle motion in infinite fluid. The methodology was used to determine the stability of the Florida Atlantic University's Ocean EXplorer (OEX) AUV. The presence of the free surface, through radiation damping, is found to suppress unsteady oscillations and thereby enhance the directional stability of the vehicle. With effects of free surface, forward speed, location and geometry of rudders, location of the center of gravity etc. all being significant factors affecting stability, a general conclusion cannot be drawn on their combined effect on the vehicle stability. The present computational methodology is therefore a useful tool to determine an underwater vehicle's stability for a given configuration and thus the viability of an intended mission a priori.
Experimental investigation of hydrodynamic force coefficients over AUV hull form
Ocean Engineering, 2009
Extensive use of autonomous underwater vehicles (AUVs) in oceanographic applications necessitates investigation into the hydrodynamic forces acting over an AUV hull form operating under deeply submerged condition. This paper presents a towing tank-based experimental study on forces and moment on AUV hull form in the vertical plane. The AUV hull form considered in the present program is a 1:2 model of the standard hull form Afterbody1. The present measurements were carried out at typical speeds of autonomous underwater vehicles (0.4-1.4 m/s) by varying pitch angles (0-151). The hydrodynamic forces and moment are measured by an internally mounted multi-component strain gauge type balance. The measurements were used to study variation of axial, normal, drag, lift and pitching moment coefficients with Reynolds number (Re) and angle of attack. The measurements have also been used to validate results obtained from a CFD code that uses Reynolds Average Navier-Stokes equations (ANSYS TM Fluent). The axial and normal force coefficients are increased by 18% and 195%; drag, lift and pitching moment coefficients are increased by 90%, 182% and 297% on AUV hull form at a ¼ 151 and Re v ¼ 3.65 Â 10 5 . These results can give better idea for the efficient design of guidance and control systems for AUV.
SIMULATION MODEL OF HYDRODYNAMICS OF UNTETHERED SUBMERSIBLE
2004
The summary: In the report questions of designing of autonomous underwater vehicles with usage simulation models are considered. The hydrodynamic model of dynamics of an autonomous underwater vehicle basing on theoretical and experimental definition of positional, rotational and inertial characteristics is designed. The program simulator of vertical maneuvering autonomous underwater under action of mid-flight propellers, bow and stern taxiing up devices and systems of change of a buoyancy and a trim is designed.
An initial evaluation of the free surface effect on the maneuverability of underwater vehicles
Ocean Engineering, 2020
The present study aims to evaluate the free surface effect on the maneuverability of an axisymmetric underwater vehicle (UV) in the horizontal plane. Therefore, the hydrodynamic captive tests, including the straight-ahead resistance, drift and rotating arm tests, are performed over various submergence depths by using URANS equations with a Reynolds stress turbulence model available in the commercial code STARCCM+. To assess the maneuverability, the forces and moments generated by the velocity components, which are obtained from captive tests, are implemented in the maneuvering equations. Moreover, analytical equations are used to calculate the loads arising from the UV accelerations, thrust and rudder, which are all assumed to remain constant with respect to depth. The results show that the behavior of the lateral force and yaw moment generated by the UV stern region reduces significantly the UV stability over the entire range of depths. The results further show that, as the UV approaches the free surface, the behavior of the lateral force and yaw moment induced by the region between the UV midlength and aft shoulder increases the UV stability, which consequently decreases the maneuverability.
Six-DOF simulations of an underwater vehicle undergoing straight line and steady turning manoeuvres
Ocean Engineering, 2018
This paper reports on numerical simulations conducted on an underwater vehicle for six-degrees of freedom (6-DOF) free running manoeuvres using Computational Fluid Dynamics (CFD). The CFD manoeuvring trials (straight line and steady turning manoeuvres) were conducted using a model-scaled BB2 submarine with movable control planes and a body force propeller represented by an actuator disk incorporating predetermined propulsion properties. The propulsion properties were obtained from captive self-propulsion simulation adopting the actual BB2 propeller. The free running simulations were validated against experimental data. The results showed that the 6-DOF CFD simulations are capable of predicting the BB2 manoeuvring characteristics with good agreement against the experimental data. The 6-DOF manoeuvring simulations carried out allow for the unsteady viscosity effects, which is usually a limitation of the traditional coefficient-based prediction method. The simulations will enable accurate determination of the vehicle's manoeuvring characteristics, which are essential for the control system design and its safe operating envelope.