Analysis of propulsion performance of wave-propelled mechanism based on fluid-rigid body coupled model

2021 ◽  
pp. 147509022110620
Author(s):  
Zongyu Chang ◽  
Zhanxia Feng ◽  
Chao Deng ◽  
Lin Zhao ◽  
Jiakun Zhang ◽  
...  
Keyword(s):  
Rigid Body ◽  
Dynamic Model ◽  
Coupled Model ◽  
Rigid Body Dynamics ◽  
Design And Optimization ◽  
Marine Vehicles ◽  
Propulsion Performance ◽  
Operation Conditions ◽  
Propulsion Force ◽  
Cfd Method

Wave-propelled mechanisms are applied to propel unmanned marine vehicles such as Wave Glider and wave-powered boats, which can convert wave energy directly into propulsion. In this paper, a fluid-rigid body coupled dynamic model is utilized to investigate the propulsion performance of the wave-propelled mechanism. Firstly, the coupled dynamic model of the wave-propelled mechanism is developed based on relative motion principle by combining rigid body dynamics model and CFD method. Then, the motion responses of wave-propelled mechanism are calculated. The relationship between the propulsion force, heave and pitch motion of hydrofoil are analyzed by using phase diagrams and the actual operation conditions of propulsion mechanism are obtained. Besides, the effects of restoring spring stiffness and wave heights on the propulsion performance are also investigated, and the vortex evolution is illustrated at different moments of movement and different restoring stiffness. These works can be helpful for the design and optimization of different kinds of wave-propelled vehicles.

scholarly journals Effects of Nonlinearity of Restoring Springs on Propulsion Performance of Wave Glider

2021 ◽  
Author(s):  
Zhanxia Feng ◽  
Zongyu Chang ◽  
Chao Deng ◽  
Lin Zhao ◽  
Jia Chen ◽  
...  
Keyword(s):  
Rigid Body ◽  
Excitation Frequency ◽  
Coupled Model ◽  
Rigid Body Dynamics ◽  
Dynamic Responses ◽  
Nonlinear Characteristics ◽  
Time Frequency ◽  
Propulsion Performance ◽  
Propulsion Mechanism ◽  
Wave Glider

Abstract Wave glider is an unmanned surface vehicle which can directly convert wave energy into forward propulsion and fulfill long-term marine monitoring. Previous study suggested that the wave motion and stiffness of restoring springs mounted on the hydrofoil are main factors affecting the propulsion performance of wave glider. In this paper, the dynamic responses and nonlinear characteristics of underwater propulsion mechanism considering the nonlinear stiffness of restoring springs are investigated based on a fluid-rigid body coupled model. Firstly, the models of propulsion mechanism with different kind of restoring spring are proposed, and the linear and nonlinear characteristics of restoring spring are considered. Then, a fluid-rigid body coupled model of wave glider is developed by coupling the rigid body dynamics model and hydrodynamic model. Dynamic responses are simulated by numerical analysis method and the nonlinear characteristics with different restoring springs are illustrated by time/frequency domain motion response and phase diagram analysis. The effects of wave excitation frequency and wave heights on the propulsion performance of wave glider are analyzed. The results show that, multi-frequency responses occurred in propulsion system. And the study suggests that the nonlinear restoring spring on the hydrofoil can be suitable for different sea condition and better propulsion performance can obtained than linear stiffness spring, which provides a reference for developing propulsion mechanism with high performance in complex marine environment.

Dynamics Analysis and Simulation of the 6-UPS Parallel Stabilizing Platform

2014 ◽  
Vol 556-562 ◽  
pp. 4297-4302 ◽  
Author(s):  
Yong Jun Liu ◽  
Hong Sheng Ding ◽  
Tie Fu ◽  
Qiang Jia ◽  
Meng Wang
Keyword(s):  
Rigid Body ◽  
Dynamic Model ◽  
Optimization Design ◽  
Rigid Body Dynamics ◽  
Response Analysis ◽  
Dynamics Analysis ◽  
Dynamics Modeling ◽  
Theoretical Derivation ◽  
Rigid Body Dynamic ◽  
Collaborative Modeling

Taking the parallel stabilizing platform based on 6-UPS structure as the research object, we deduced the multi-rigid-body dynamics modeling process by using the Lagrange method, and finished the dynamic response analysis of the platform. Then we conducted the collaborative modeling and simulation of the coupled dynamics analysis of the platform with ProE, ANSYS and ADAMS. The results indicate the correctness of the theoretical derivation of the multi-rigid-body dynamic model and the feasibility and necessity of collaborative simulation of the coupled dynamic model, which lay a foundation for further optimization design and practical application of the parallel platform.

Influence of the Obliquity of Fin Ray on Propulsion Performance for Biorobotic Underwater Undulating Propulsor

2011 ◽  
Vol 52-54 ◽  
pp. 267-272 ◽  
Author(s):  
Yong Hua Zhang ◽  
Jian Hui He ◽  
Guo Qing Zhang
Keyword(s):  
Three Dimensional ◽  
Navier Stokes ◽  
Environment Friendly ◽  
Contour Maps ◽  
Propulsion Performance ◽  
Fin Ray ◽  
Propulsion Force ◽  
Computational Fluid Dynamics Cfd ◽  
Motion Performance ◽  
Cfd Method

This paper aims to understand influence of the obliquity of fin ray on its motion performance. An environment-friendly propulsion system mimicking undulating fins of stingray had been built. Investigations were presented by using three-dimensional unsteady Computational Fluid Dynamics (CFD) method. An unstructured, grid-based, unsteady Navier-Stokes solver with automatic adaptive remeshing was used to compute the unsteady flow around the fin through twenty complete cycles. The pressure distribution on fin surface was computed and integrated to provide fin forces which were decomposed into lift and thrust. Vortex contour maps of the fin with different obliquity of fin ray were displayed and compared. Finally, we draw a conclusion that the generated propulsion force of the biomimetic propulsor is gradually increase with the obliquity of the fin ray from 0 degree till a certain angle and then gradually decrease with the obliquity of the fin ray from the certain angle till 90 degree. The results provide valuable information for the optimization of robotic underwater undulating propulsor design.

scholarly journals Slipping–rolling transitions of a body with two contact points

2021 ◽  
Author(s):  
Mate Antali ◽  
Gabor Stepan
Keyword(s):  
Rigid Body ◽  
Contact Point ◽  
Static Friction ◽  
Rigid Body Dynamics ◽  
Contact Forces ◽  
Friction Forces ◽  
Contact Points ◽  
Body Dynamics ◽  
Coulomb Model ◽  
Rigid Surfaces

AbstractIn this paper, the general kinematics and dynamics of a rigid body is analysed, which is in contact with two rigid surfaces in the presence of dry friction. Due to the rolling or slipping state at each contact point, four kinematic scenarios occur. In the two-point rolling case, the contact forces are undetermined; consequently, the condition of the static friction forces cannot be checked from the Coulomb model to decide whether two-point rolling is possible. However, this issue can be resolved within the scope of rigid body dynamics by analysing the nonsmooth vector field of the system at the possible transitions between slipping and rolling. Based on the concept of limit directions of codimension-2 discontinuities, a method is presented to determine the conditions when the two-point rolling is realizable without slipping.

scholarly journals Numerical Investigation on Hydrodynamic Performance of a Portable AUV

2021 ◽  
Vol 9 (8) ◽  
pp. 812
Author(s):  
Lin Hong ◽  
Renjie Fang ◽  
Xiaotian Cai ◽  
Xin Wang
Keyword(s):  
Numerical Investigation ◽  
Dynamic Model ◽  
Autonomous Underwater Vehicle ◽  
Dynamic Performance ◽  
Plane Motion ◽  
Hydrodynamic Performance ◽  
Wave Forces ◽  
Modeling And Control ◽  
Experiment Platform ◽  
Cfd Method

This paper conducts a numerical investigation on the hydrodynamic performance of a portable autonomous underwater vehicle (AUV). The portable AUV is designed to cruise and perform some tasks autonomously in the underwater world. However, its dynamic performance is strongly affected by hydrodynamic effects. Therefore, it is crucial to investigate the hydrodynamic performance of the portable AUV for its accurate dynamic modeling and control. In this work, based on the designed portable AUV, a comprehensive hydrodynamic performance investigation was conducted by adopting the computational fluid dynamics (CFD) method. Firstly, the mechanical structure of the portable AUV was briefly introduced, and the dynamic model of the AUV, including the hydrodynamic term, was established. Then, the unknown hydrodynamic coefficients in the dynamic model were estimated through the towing experiment and the plane-motion-mechanism (PMM) experiment simulation. In addition, considering that the portable AUV was affected by wave forces when cruising near the water surface, the influence of surface waves on the hydrodynamic performance of the AUV under different wave conditions and submerged depths was analyzed. Finally, the effectiveness of our method was verified by experiments on the standard models, and a physical experiment platform was built in this work to facilitate hydrodynamic performance investigations of some portable small-size AUVs.

New solutions of classical problems in rigid body dynamics

2015 ◽  
Vol 69 ◽  
pp. 40-44
Author(s):  
H.M. Yehia ◽  
E. Saleh ◽  
S.F. Megahid
Keyword(s):  
Rigid Body ◽  
Rigid Body Dynamics ◽  
Body Dynamics

scholarly journals In Silico Single-Molecule Manipulation of DNA with Rigid Body Dynamics

2014 ◽  
Vol 10 (2) ◽  
pp. e1003456 ◽  
Author(s):  
Pascal Carrivain ◽  
Maria Barbi ◽  
Jean-Marc Victor
Keyword(s):  
Rigid Body ◽  
Single Molecule ◽  
In Silico ◽  
Rigid Body Dynamics ◽  
Body Dynamics ◽  
Single Molecule Manipulation
Sign in / Sign up

Export Citation Format

Share Document