A Computational Fluid Dynamics Analysis of an Ideal Anguilliform Swimming Motion

AbstractResearchers have been studying swimming motions of various fishes for numerous years. The scope of the current work is to validate the results of an ideal anguilliform swimming motion developed by Vorus and Taravella (2011) by modeling the motion in a commercially available Computational Fluid Dynamics (CFD) code. The ideal swimming motion developed by Vorus and Taravella (2011) shows that thrust can be generated by an anguilliform swimmer without producing wake-induced drag. In the current work, ANSYS Fluent was used to discretize and solve Euler's equation and the continuity conservation. The results for fluid velocity on the body of the anguilliform show an average agreement within ±3% to the potential flow slender body formulation of Vorus and Taravella (2011). There is also no induced circulation in the wake of the anguilliform in the CFD solution, which confirms the absence of wake-induced drag. The results suggest that it is plausible for an undulating body to produce thrust that is purely inertial and is produced by body accelerations acting through hydrodynamic added mass.

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Hydrodynamical effect of parallelly swimming fish using computational fluid dynamics method

PLoS ONE ◽

10.1371/journal.pone.0250837 ◽

2021 ◽

Vol 16 (5) ◽

pp. e0250837

Author(s):

Keisuke Doi ◽

Tsutomu Takagi ◽

Yasushi Mitsunaga ◽

Shinsuke Torisawa

Keyword(s):

Fluid Dynamics ◽

Computational Fluid Dynamics ◽

Flow Field ◽

Flow Speed ◽

The Body ◽

Fluid Force ◽

Fish Model ◽

Swimming Motion ◽

Computational Fluid Dynamics Analysis ◽

Swimming Efficiency

Fish form schools because of many possible reasons. However, the hydrodynamic mechanism whereby the energy efficiency of fish schools is improved still remains unclear. There are limited examples of fish models based on actual swimming movements using simulation, and the movements in existing models are simple. Therefore, in this study, we analyzed the swimming behavior of Biwa salmon (Oncorhynchus sp., a salmonid fish) using image analyses and formulated its swimming motion. Moreover, computational fluid dynamics analysis was carried out using the formulated swimming motion to determine the fluid force acting on the fish body model with real fish swimming motion. The swimming efficiency of the fish model under parallel swimming was obtained from the calculated surrounding fluid force and compared for different neighboring distances. The flow field around the fish model was also examined. The swimming efficiency of two fish models swimming parallelly was improved by approximately 10% when they were separated by a distance of 0.4L, where L is the total length of the model. In addition, the flow field behind the fish body was examined under both inphase and antiphase conditions and at inter-individual distances of 0.8L and 1.2L. The apparent flow speed in the distance range of 0.5–2.0L from the midpoint of the snouts of the two individuals was lower than the swimming speed. The pressure distribution on the fish model showed an elevated pressure at the caudal fin. Interestingly, we obtained an isopleth map similar to that of a caudal peduncle. To avoid a negative thrust, the aft part of the body must be thin, as shown in the isopleth map obtained in this study.

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Computational fluid dynamics analysis of a modified Savonius rotor and optimization using response surface methodology

Wind Engineering ◽

10.1177/0309524x17709732 ◽

2017 ◽

Vol 41 (5) ◽

pp. 285-296 ◽

Cited By ~ 2

Author(s):

Haris Moazam Sheikh ◽

Zeeshan Shabbir ◽

Hassan Ahmed ◽

Muhammad Hamza Waseem ◽

Muhammad Zubair Sheikh

Keyword(s):

Fluid Dynamics ◽

Computational Fluid Dynamics ◽

Response Surface Methodology ◽

Response Surface ◽

Design Of Experiment ◽

Coefficient Of Performance ◽

Speed Ratio ◽

Ansys Fluent ◽

Computational Fluid Dynamics Analysis ◽

Parametric Effects

This article aims to present a two-dimensional parametric analysis of a modified Savonius wind turbine using computational fluid dynamics. The effects of three independent parameters of the rotor, namely, shape factor, overlap ratio, and tip speed ratio on turbine performance were studied and then optimized for maximum coefficient of performance using response surface methodology. The rotor performance was analyzed over specific domains of the parameters under study, and three-variable Box-Behnken design was used for design of experiment. The specific parametric combinations as per design of experiment were simulated using ANSYS Fluent®, and the response variable, coefficient of performance (Cp), was calculated. The sliding mesh model was utilized, and the flow was simulated using Shear Stress Transport (SST) k − ω model. The model was validated using past experimental results and found to predict parametric effects accurately. Minitab® and ReliaSoft DOE++® were used to develop regression equation and find the optimum combination of parameters for coefficient of performance over the specified parametric domains using response surface methodology.

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Flow Characteristics of Disk Bypass Pipeline Inspection Gauge (PIG) in Natural Gas Pipelines using Computational Fluid Dynamics

CFD letters ◽

10.37934/cfdl.13.4.1137 ◽

2021 ◽

Vol 13 (4) ◽

pp. 11-37

Author(s):

Md Insiat Islam Rabby ◽

Siti Ujila Masuri ◽

Ahmad Syakir Fariz Samsul Kamal ◽

Zulkiflle Leman ◽

Abdul Aziz Hairuddin ◽

...

Keyword(s):

Fluid Dynamics ◽

Computational Fluid Dynamics ◽

Control Volume ◽

Fluid Velocity ◽

Flow Characteristics ◽

Differential Pressure ◽

Ansys Fluent ◽

Pipeline Inspection ◽

Natural Gas Pipelines ◽

Opening Section

Disk bypass pipeline inspection gauge (PIG) is considered as an efficient device for pigging operations including cleaning, maintaining and inspecting pipelines. The PIG performance is influenced by the fluid flow characteristics as PIG moves forward due to differential pressure of fluid around the PIG. This study focuses on flow characterization of fluid around disk bypass PIG for natural gases pipelines including methane, ethane, and butane using computational fluid dynamics approach. The control volume method with steady state Turbulent k-? model was applied for simulation purposes using ANSYS Fluent 19 software. Fluid velocities at different sections around PIG and differential pressure were investigated for various bypass opening percentages. The results showed that by increasing bypass opening percentages from 5% to 15%, fluid velocity at bypass opening section has reduced 28.28%, 40.43%, and 21.21% for ethane, butane, and methane, respectively, while differential pressure reduced 88%, 86% and 89%. This indicated that 15% bypass opening percentage provided the best flow characteristics among all cases considered. At 15% bypass opening percentage, methane resulted in the lowest fluid velocity at bypass opening section and lowest differential pressure compared to others. Additionally, a correlation of differential pressure of these gases as a function of bypass opening percentage and other parameters was also developed for first time. All results are important for design selection of PIG parameters for efficient pigging operation.

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Optimization on submarine stern design

Proceedings of the Institution of Mechanical Engineers Part M Journal of Engineering for the Maritime Environment ◽

10.1177/1475090215625673 ◽

2016 ◽

Vol 231 (1) ◽

pp. 109-119 ◽

Cited By ~ 1

Author(s):

Mohammad Moonesun ◽

Yuri Mikhailovich Korol ◽

Hosein Dalayeli ◽

Davood Tahvildarzade ◽

Mehran Javadi ◽

...

Keyword(s):

Fluid Dynamics ◽

Computational Fluid Dynamics ◽

Body Shape ◽

Fluid Velocity ◽

Point Of View ◽

Field Variation ◽

Wake Field ◽

Computational Fluid Dynamics Analysis ◽

The Status ◽

Minimum Resistance

This article discusses the optimum hydrodynamic shape of the submarine stern based on the minimum resistance. Submarines consist of two major categories of hydrodynamic shape: the teardrop shape and the cylindrical middle-body shape. Due to the parallel middle-body shape in most of the naval submarines, those with cylindrical middle-body are studied here. The bare hull has three main parts: bow, cylinder and stern. This article proposes an optimum stern shape by the computational fluid dynamics method via Flow Vision software. In the hydrodynamic design point of view, the major parameters of the stern included the wake field (variation in fluid velocity) and resistance. The focus of this article is on the resistance at fully submerged mode without any regard for free surface effects. First, all the available equations for the stern shape of submarine are presented. Second, a computational fluid dynamics analysis has been performed according to the shape equations. For all the status, the following parameters are assumed to be constant: velocity, dimensions of domain, diameter, bow shape and total length (bow, middle and stern length).

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Computational Fluid Dynamics Analysis of the Stall Characteristics of a Wing Designed Based on Prandtl’s Minimum Induced Drag

2018 Applied Aerodynamics Conference ◽

10.2514/6.2018-3009 ◽

2018 ◽

Cited By ~ 2

Author(s):

Seung Yoo

Keyword(s):

Fluid Dynamics ◽

Computational Fluid Dynamics ◽

Dynamics Analysis ◽

Induced Drag ◽

Computational Fluid Dynamics Analysis

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Computational Fluid Dynamics Analysis of Compressible Flow Through a Converging-Diverging Nozzle using the k-ε Turbulence Model

Engineering, Technology & Applied Science Research ◽

10.48084/etasr.3140 ◽

2020 ◽

Vol 10 (1) ◽

pp. 5180-5185 ◽

Cited By ~ 1

Author(s):

M. W. Khalid ◽

M. Ahsan

Keyword(s):

Fluid Dynamics ◽

Computational Fluid Dynamics ◽

Combustion Chamber ◽

Turbulence Model ◽

High Velocity ◽

Chemical Potential ◽

Low Velocity ◽

Ansys Fluent ◽

Computational Fluid Dynamics Analysis ◽

Flow Through

The thrust produced by a rocket motor is mainly dependent upon the expansion of the product gases through a nozzle. The nozzle is used to accelerate the gases produced in the combustion chamber and convert the chemical-potential energy into kinetic energy so that the gases exit the nozzle at very high velocity. It converts the high pressure, high temperature, and low-velocity gas in the combustion chamber into high-velocity gas of lower pressure and low temperature. The design of a nozzle has particular importance in determining the thrust and performance of a rocket. In recent years, it has received considerable attention as it directly impacts the overall performance of the rocket. This paper aims to analyze the variation of flow parameters like pressure, Mach number, and velocity using Finite Volume Method (FVM) solver with the standard k-ε turbulence model in Computational Fluid Dynamics (CFD). The simulation of shockwave inside the divergent nozzle section through CFD is also investigated. In this regard, a nozzle has been designed using Design Modeler, and CFD analysis of flow through the nozzle has been carried out using ANSYS Fluent. The model results are compared with theoretically calculated results, and the difference is negligible.

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