The dynamic characteristics of the pressure and velocity fields unsteady incompressible laminar turbulent wakes behind a circular cylinder are investigated numerically analyzed physically. governing equations, written in formulation solved using 2-D finite volume method. initial mechanism for vortex shedding is demonstrated body forces evaluated. flow Re = 1000 & 3900 simulated k-? standard, Realizable SST turbulence models. capabilities these models to compute lift drag coefficients...

Shipbuilding industry is one of the hardest metal industries with several chemical and hazardous material exposures.Most traditional production processes such as welding, painting, blasting fiberglass have direct impacts on workers' health safety well adverse effects environment.A huge volume wastes pollutants being released during shipbuilding repairing which poses major risk human environmental quality.Thus, this article highlights current issues challenges green recycling also encompasses...

Energy Efficiency Design Index (EEDI) [1] was introduced by the International Maritime organization (IMO) to stimulate innovation and technical development of all elements that increase level energy efficiency a ship at design stage. Sea going ships over 400 gross tonnage are considered in current regulation EEDI. Inland not covered EEDI regulations IMO. As inland vessels share 0.6% global CO2 emission [2], reduction attempt will have bigger impact. But from commercial point view country...

The wave generated by flow around cambered hydrofoil NACA 4412 near free surface is predicted numerically in this study. To solve Reynolds Averaged Navier-Stokes (RANS) equation, two-dimensional implicit Finite Volume Method (FVM) applied. Realizable turbulence model has been implemented at different submergence depth to chord ratios (h/c) ranging from 1 5 for capturing the zone. Of Fluid (VOF) method applied determine effect of water an angle attack 50 hydrofoil. Firstly, computed result...

Though inland ships account for a small portion of the total global CO2 emissions from shipping, individual country’s economic and environmental perspective, this is very important. To reduce sea-going by increasing energy efficiency, International Maritime Organization (IMO) adopted generalized Energy Efficiency Design Index (EEDI) in 2011. However, due to variation environmental, geographic conditions, EEDI cannot be established similar fashion that IMO. Shallow restricted water effects,...

This paper numerically investigated the influence of falling height on behavior skid-launching free-fall lifeboat (FFLB) in regular waves.The boat has been treated as a rigid body when differential equations motion for four phases, i.e., sliding or ramp phase, rotation phase and water entry were solved time domain.The hydrodynamic characteristics studied different heights such H = 1.5m, 1.75m 2.00m.Horizontal vertical excursions axis have computed at along with its horizontal...

A generalized CO 2 emission benchmark (energy efficiency design index) cannot be established for inland ships in a similar fashion like the one by International Maritime Organization seagoing vessels. Difference environmental, geographical and economic conditions, example, shallow restricted water effects, different fuel quality (to reduce operational cost), reduction speed, increase engine power, carrying capacity cargo availability, forbids direct use of energy index as formulated...

In the present paper, a marine propeller design method has been presented based on lifting line theory and surface correction factors. The developed applied for whose blade outline is symmetrical about mid- chord mean chosen parabolic which also mid-chord. So no pitch necessary. Only camber required. symmetric to avoid cavitation. determined by requirement that designed load distribution be obtained. used wake adapted with an adaptation of vortex lattice method. Assumption loading...

The current problem studies the mixed convective heat transport by heatlines in lid‐driven cavity having wavy heated walls with two diamond‐shaped obstacles. left and right vertical are both cold, whereas top wall is adiabatic, bottom heated. relevant governing equation has been calculated through using finite element method as well Galerkin weighted residual approach. implications of Reynolds number (10 ≤ Re 500), Richardson (0.01 Ri 10), Hartman (0 Ha 100), Prandtl (0.015 Pr Undulations (1...

Axisymmetric turbulent viscous flow around sphere is computed using finite volume method based on Reynolds-averaged Navier-Stokes (RANS) equations. Two-dimensional axisymmetric solver has been used to analyze at Reynolds number of 5×106. Spalart-Allmaras (S-A) and shear stress transport (SST) k-ω turbulence models are capture flow. The numerical results in terms the skin friction coefficient, pressure coefficient drag for different numbers have shown either graphically or tabular form....

This paper presents results from the application of genetic algorithm (GA) technique to design optimization hydrofoil and marine propeller incorporating potential based boundary element method (BEM). Although, larger population size as implemented by simple (SGA) could find optimal individual after a fewer number generations than smaller size, it is penalized longer amount time evaluate fitness in every generation. An investigation is, therefore, conducted this research implement micro...

This paper presents a numerical study with pressure-based finite volume method for prediction of non-cavitating and time dependent cavitating flow on hydrofoil. The phenomenon cavitation is modeled through mixture model. For the simulation flow, bubble dynamics model used to investigate unsteady behavior describe generation evaporation vapor phase. focuses choosing mesh size influence turbulence Three models such as Spalart-Allmaras, Shear Stress Turbulence (SST) k-ω Re-Normalization Group...

In this study the wave generated by flow around a shallowly submerged cambered hydrofoil near free surface is simulated numerically. The standard NACA 4412 section used for ease of comparison with available experimental data. A commercial computational fluid dynamics (CFD) code FLUENT based on finite volume technique analysis two dimensional section. k-ɛ turbulence model has been implemented to simulate turbulent past foil in zone at different submergence ratios (h/c). To get elevation,...

The objective of this paper is to investigate the hydrodynamic characteristics high speed catamaran and trimaran ships at different speeds finite depths using Computational Fluid Dynamics (CFD) techniques. Three dimensional Rankine Source Panel Method with non-linear free-surface boundary condition used capture potential flow around ship hull. Wave pattern, wave resistance, sinkage trim for varying lateral longitudinal separation hull water are determined compared each other spacing depth...

This paper investigates various hydrodynamic characteristics of two conventional ships namely Wigley hull and Series 60 ship by commercial CFD software named Shipflow.Zonal approach is applied to incorporate 'potential flow solver' in the region outside boundary layer wake, 'boundary thin near 'Navier Stokes wake successively.Finally free-surface wave pattern, elevation, pressure coefficient on hull, streamline different resistance components at speeds are computed validated comparing with...

Flow field around different modern benchmark ship hull with self propulsion characteristics at varying longitudinal positions of rudder is computed using Computation Fluid Dynamics (CFD) technique. Numerical study performed bare first to determine free surface wave elevation and resistance components. Zonal approach applied incorporate 'potential flow solver' in the region outside boundary layer & wake, 'boundary thin near 'Navier Stokes wake successively. Lifting Line method coupled RANS...

This paper presents a numerical study of the non-cavitating and cavitating flow around CAV 2003 hydrofoil. The phenomenon cavitation is modeled through mixture model. For solution bubble dynamics model used to describe generation evaporation vapor phase. focuses on influence turbulence different mesh sizes in computation. Three models such as Spalart-Allmaras, Shear Stress Turbulence (SST) k-? model, RNG with enhanced wall treatment are capture turbulent boundary layer along hydrofoil...