Prasanta Sahoo

• PhD
• Visiting Faculty at UNSW Canberra

An attempt has been made to validate the frequency-domain seakeeping code presented in this paper. Two-dimensional hydrodynamic added mass and damping coefficients are calculated by using Ursell [1] and Tasai's [2], [3] multipole expansion theory and conformal mapping. Lewis conformal mapping technique is used to obtain the hydrodynamic coefficient...

In this paper, an attempt has been made to predict the performance of a planing catamaran using a mathematical model. Catamarans subjected to a common hydrodynamic lift, have an extra lift between the two asymmetric half bodies. In order to develop a mathematical model for performance prediction of planing catamarans, existing formulas for hydrodyn...

In this study, an attempt has been made to investigate the water-entry characteristics of the high-speed parallel projectile numerically. The shear stress transport k-ω turbulence model and the Zwart-Gerber-Belamri cavitation model based on the Reynolds-Averaged Navier–Stokes method were used. The grid independent inspection and grid convergence in...

In this paper an attempt has been made to assess the capability of numerical algorithm based on Reynolds Averaged Navier Stokes (RANS) for predicting the motion characteristics of the planing hull in calm water and regular waves. The focus of the present study is the impact of interceptors on the sea keeping quality of a planing vessel investigated...

This paper presents CFD (Computational Fluid Dynamics) simulations of the performance of a planing hull in a calm-water condition, aiming to evaluate similarities and differences between results of different CFD models. The key differences between these models are the ways they use to compute the turbulent flow and simulate the motion of the vessel...

The Floating Production Storage and Offloading Unit (FPSO) is an offshore vessel that produces and stores crude oil prior to tanker transport. Robust prediction of extreme hawser tensions during Floating Production Storage and Offloading (FPSO) operation is an important safety concern. Excessive hawser tension may occur during offloading operations...

Computational fluid dynamics (CFD) techniques are becoming increasingly popular in analyzing fluid flow problems in almost all branches of engineering, especially in resistance prediction of ships where complex fluid flow exists, although absolute accuracy is still limited. Application of CFD techniques in resistance prediction of ships is no longe...

This study was built upon previous works conducted by the authors in a series of numerical studies on submarine hydrodynamics and is aimed at enhancing the accuracy of computational fluid dynamics (CFD) application processes, which estimate the hydrodynamic performance of underwater vehicles for steady translation conditions in the horizontal and v...

Planing hulls are quite well known for their wide application in coastal seas. These vessels can reach high-speeds using the hydrodynamic pressure acting on the wetted area, which tends to raise the bow of the vessel thereby decreasing wave-making resistance. However, operation at super high-speeds necessitates accurate performance prediction of th...

As a vital key part of the modern offshore wind energy industry, floating offshore wind turbines (FOWT) are built to generate green renewable energy. Robust prediction of extreme loads during FOWT operation is an important safety concern. In this paper, the FAST code has been used to analyse offshore wind turbine internal bending moments due to env...

computational fluid dynamics (CFD) as an estimation tool for the hydrodynamic performance of submarines. The Defense Advanced Research Projects Agency (DARPA) SUBOFF model is adopted as a benchmark owing to the availability of experimental data for validation. The computational modeling is based on the Reynolds-averaged Navier–Stokes equations solv...

This paper presents a numerical study on the self-propulsive performance of the DARPA SUBOFF submarine fitted with the INSEAN E1619 propeller using computational fluid dynamics (CFD). The present study has been undertaken as part of a series of computational analyses aiming to improve future hull forms and propeller designs. The commercial CFD pack...

In this paper, an attempt has been made to predict the performance of a planing catamaran using a mathematical model. Catamarans subjected to a common hydrodynamic lift, have an extra lift between the two asymmetric half bodies. In order to develop a mathematical model for performance prediction of planing catamarans, existing formulas for hydrodyn...

This paper presents a rapid resistance estimation method (RREM) for trimarans in early design stages. The method considers the total resistance as the combination of the viscous and wave-making resistance. The viscous resistance is the product of the form factor (1+k) and the frictional resistance calculated by ITTC-1957 equation. The wave-making r...

The Floating Production Storage and Offloading (FPSO) unit are one of the most popular approaches to exploiting petroleum and natural gas. During the offloading operation, the responses of FPSO and shuttle tanker become complicated because of the hydrodynamic interactions. This paper presents a comprehensive study on the coupling effects on hydrody...

Designing a suitable propeller to meet the desired thrust and torque and minimizing cavitation occurrence for a marine vessel at a given speed has been explored over the years by various researchers. In a conventional design process, either propeller charts or regression equations have been used. However, computational fluid dynamics (CFD) has been...

The Floating Production Storage and Offloading (FPSO) unit are one of the most popular approaches to exploiting petroleum and natural gas. Tandem offloading and side-by-side offloading are two basic methods used in transporting oil or gas from FPSO to shuttle tanker. During the offloading operation, the responses of FPSO and shuttle tanker become c...

There has been widespread use of 2A12 aluminum alloys in marine industry applications with exposure to harsh and complex environments. Ceramic oxide coatings were carried out on the surface of 2A12 aluminum alloys by a micro-arc oxidation (MAO) process. The microstructure, phase composition, wear resistance, and corrosion behavior of the MAO coatin...

This paper attempts to present a mathematical model to predict hydrodynamic coefficients of a heeled planing hull in vertical plane. This model has been developed by using 2D+T theory and theoretical solution of the water entry of wedge section bodies. Sectional hydrodynamic force acting on the vessel is determined and then extended over the entire...

Structural optimization is one of the important aspects of the overall ship design process. A number of advanced optimization tools are available. As these tools require large computational resources, they are not suitable for use in the preliminary design stages, when many important aspects of the design, such as overall dimensions and hull config...

A self-blending method has been developed and applied to the modification of a bulbous bow. The method is capable of transforming ship hulls automatically. In this method, few representative number of cross sections (the key points of the cross sections) of the baseline geometry are selected. New cross sections are generated through merging the two...

Determination of forces acting on planing hulls in maneuvering has been turned into an interesting problem during the last decade. Different methods, based on mathematical or empirical approaches, are elicited to compute hydrodynamic forces and moments acting on the boat in different simplified conditions, such as steady yawed or heeled conditions....

The present paper attempts to addresses the roll motion of high-speed planing hulls in oblique waves. A mathe¬¬matical model is developed by using added mass theory and asymmetric water entry of wedge section bodies. Equations for added mass terms in roll direction are presented and are used to find the final hydrodynamic moment acting on the boat....

In order to enhance the corrosion resistance of mooring chain, the composite coatings are carried out on the surface of 22MnCrNiMo steel for mooring chain by double-pulsed electrodeposition technology using centrifugal force in the rotating device. The microstructure and anti-corrosion performance of the composite coatings have been investigated ex...

In this paper, an attempt has been made to investigate the effects of propeller load changes against its performance in open water conditions. Load change of different propellers in a multi-propulsion vessel varies and there is scarce research in this area. The authors have made an endeavor to get a better understanding of the factors causing the l...

In order to enhance the corrosion resistance of a drill pipe for an offshore platform, micro-arc oxidation (MAO) coatings were deposited on the surface of an aluminum alloy drill pipe by MAO technology. The microstructure and anticorrosion performance of the MAO coatings were investigated experimentally. This paper mainly focuses on the experimenta...

Marine fouling on the hull of surface vessels is a topic of increasing importance in the maritime field for its environmental and financial impacts. Recent research developments have introduced mathematical models dealing with the frictional resistance associated with fouling. Herein, an implementation of these models in a numerical code to predict...

In a creative design process of planing craft, stepped hulls could fill a gap in the planing craft industries in response to low drag and high speed demands. However, there exists a need for new computational tools for performance prediction of such hulls. Therefore, in the current work, an attempt has been made to develop a mathematical model for...

In order to improve the high temperature oxidation resistance of exhaust pipes, the nanocomposite coatings are carried out on the surface of exhaust pipe by pulsed current electrodeposition technology, and the microstructure and oxidation behavior of the nanocomposite coatings are investigated experimentally. This paper mainly focuses on the experi...

During the last 5 years, there have been some major advances in roll motion modeling of planing boats. In this article, previous studies have been reviewed, and an attempt has been made to propose a relatively straightforward method for computing roll motion coefficients and thus predicting the roll response of a planing vessel in calm water on a s...

Heading In the recent past, developments of computational fluid dynamics (CFD) tool in analyzing the hydrodynamic behavior of hull forms has undergone significant changes. Hydrodynamic analyses have been increasingly dependent on commercial software , such as ANSYS FLUENT, ABAQUS, STAR CCM+ etc., to solve fluid-structure interactions. However, in t...

In a creative design process of high-speed craft stepped planing hulls could fill a gap in the high-speed craft industries in response to low drag and high-speed speed demands. In this regards, there exists a need for new computational tools for performance prediction of such hulls. Therefore, in the current work, an attempt has been made to develo...

In order to improve the corrosion resistance of the drill pipe, the alumina ceramic membrane is coated on the surface of aluminum alloy drill pipe of offshore platform by micro arc oxidation technology. This paper mainly focuses on the experimental work to determine the effect of the nano-MoS2 content in the solution on the micro morphology, elemen...

Determination of forces acting on planing hulls in maneuvering has been turned into an interesting problem during the last decade. Different methods, based on mathematical or empirical approaches, are elicited in order to compute hydrodynamic forces and moments acting on the boat in different simplified conditions such as steady yawed or heeled con...

In this study an attempt has been made to study the hydrodynamic performance of pumpjet propulsor. Numerical investigation based on the Reynolds Averaged Navier–Stokes (RANS) computational fluid dynamics (CFD) method has been carried out. The structured grid and SST k–ω turbulence model have been applied. The numerical simulations of open water per...

This paper attempts to undertake a comparative analysis of resistance characteristics between newly developed asymmetrical catamaran hull forms which were derived from existing conventional NPL series of round bilge catamaran hull forms by Molland, Wellicome and Couser (1994). A set of asymmetrical catamaran hull forms with waterline length of 1.6...

Observations by crew of high-speed planing boats and sea trial tests have indicated that high-speed planing hulls suffer poor longitudinal and transverse instabilities, and boat may experience unfavorable motions due to any small environmental excitation. In this regard, dynamic motions of planing boats have been investigated over the last thirty y...

In this paper an attempt has been made to investigate the resistance characteristics of high-speed round bilge hull forms fitted with a vane in the stern region of the vessel. The Hull Vane ® is a fixed foil located below the waterline, aft of the stern of the vessel. The Hull Vane® reduces the generation of waves and the vessel’s motions in waves....

This paper attempts to carry out a CFD analysis on total resistance for trimaran hull forms based on established NPL systematic series which are high-speed round bilge hull forms. The resistance of high-speed trimaran hull forms have been determined using ANSYS FLUENT, a CFD software package. A systematic series of round bilge demi-hulls were gener...

In this paper, an attempt has been made to numerically model the responses of mooring lines on large floating structures (LFS) deployed in South China Sea. In this paper, a preliminary study has been undertaken to locate the mooring form and determine the mooring hydrodynamic response characteristics when LFS are deployed in water depths of under 1...

In this study, an attempt has been made to study the cavitating flows of a pumpjet propulsor. A numerical study based on the unsteady Reynolds-averaged Navier-Stokes computational fluid dynamics method of homogeneous multiphase using structured grids and the shear stress transport (SST) k-ω turbulence model has been carried out. Considering the eff...

The paper deals with the numerical modeling of sway, roll and yaw motions of a ship for flared up conditions with zero or nonzero forward speeds in sinusoidal waterway. To compute hydrodynamic forces, we employ nonlinear roll restoring characteristics and speed dependent strip theory that are obtained from the Frank's close-fit method. The governin...

The paper investigates the motion response of a floating body under the action of small amplitude regular waves and determines the influence of uncoupled as well as coupled systems through an analytical approach. The governing equations of motion describing the overall balance between the wave-exciting force with the linear form of inertial, dampin...

This study attempts to extend the analysis of several resistance prediction procedures based on experimental work carried out by researchers and, subsequently, wave resistance estimation as illustrated in Part I of this study by Sahoo et al. (2007)4. Sahoo , P K , Salas , M and Schwetz , A . 2007 . Practical evaluation of resistance of high-speed c...

The article deals with the numerical modelling of sway, roll and yaw motions of a floating body in time domain and investigates motion instability primarily due to non-linear roll restoring characteristics in the absence of auto piloting mechanism. To compute hydrodynamic forces, we consider non-linear roll restoring characteristics and speed depen...

Although catamaran configuration has been around for a longtime, it is only in the recent past that such hull forms have seen unprecedented growth in the high-speed ferry industry. One of the design challenges faced by naval architects is accurate prediction of the hydrodynamic characteristics of such vessels primarily in the areas of resistance, p...

Vesselmotionisanaspectofdesignthatrequiresahighdegreeofconsiderationwithregardto passengercomfort. Withinthe lasttwodecades,extensiveresearchworkhasresultedin developmentof numericalandanalyticalmethodsforthepredictionofheaveandpitchmotionsofcatamaranhullforms. However, in the recent past, there appears to be a strong interest in the development of...

This paper deals with the mathematical modelling of the roll motion of a floating body in regular waves in beam seas for non-restrained conditions. The hydrodynamic forces are computed with the application of strip theory, and frequency dependent sectional added mass moment of inertia and damping are integrated over the length of the body by using...

The question of the wave generation by river vessels is one that has been studied at length by many researchers, particularly since the advent of the RiverCat, a catamaran designed specifically for operation on the Parramatta River, which leads into Sydney Harbour. There was good correlation between the measured height of the generated waves and th...

This paper establishes a regression equation to estimate the wave resistance of a systematic series of high-speed, hard-chine catamarans based on the data attained by using SHIPFLOW, a CFD software package. The primary aim of this investigation is to determine wave resistance characteristics of slender hard-chine configurations of catamaran hull fo...

The first part of the research presented was published in the proceedings of Sea Australia 2000 (Bojovic and Sahoo 2000), which presented the results of the tests of model #13 with stern wedges, with and without spray rails. The wedges were faired into the hull surface at the bilges and had 0°, 4°, 7° and 10° angles relative to the hull surface. Tw...

USNS "X-Craft" built as a catamaran with decreased water-plane area shows some practical advantages as multi-hull combatants. It comprises of a large deck area per tonne of displacement, wide (and free from superstructure) upper deck, high performance in terms of high-speed and enhanced seaworthiness. In this paper two alternatives have been propos...

Computational fluid dynamics (CFD) techniques are becoming increasingly popular in analysing flow problems in almost all branches of engineering, especially in resistance prediction of ships where complex fluid flow exists. While towing-tank tests provide better absolute accuracy, the knowledge of the importance of modifica tion to hull forms is li...

Although the catamaran configuration has been known for a long time, it is only in the recent past that such hull forms have enjoyed unprecedented usage in the high-speed ferry industry. One of the design challenges faced by naval architects is the accurate prediction of the hydrodynamic characteristics of such vessels, primarily in the areas of re...

Catamarans continue to increase in size and application, with proposals circulating within the shipbuilding industry for bigger and better designs than the present generation of catamarans. The present paper attempts to show a comparison of resistance calculation of a small fast catamaran carried out by experimental and CFD techniques. Experimental...

Although catamaran configuration has been around for a longtime, it is only in the recent past that such hull forms have seen unprecedented growth in the high-speed ferry industry. One of the design challenges faced by naval architects is accurate prediction of the hydrodynamic characteristics of such vessels primarily in the areas of resistance, p...