Mangroves have been proven for their role as a natural barrier to various environmental risks such abrasion and erosion. It helped improve water quality, reducing storms providing habitat marine species. Not only playing an essential in maintaining the surface, crucial several aspects ecology, economy, socio-culture. This study aims understand effects of arrangement length mangrove trees wave transmission. The present is performed on mesh-free CFD method, i.e., smoothed particle...

Abstract The rising demand for liquefied natural gas (LNG) has made membrane-type LNG tanks popular due to their effectiveness in reducing sloshing effects. However, incidents involving free surface effects during voyages still occur. This study examines the impact of floating baffles on waves under force oscillation conditions, including coupled motions (sway and rolling) represent actual ship tank scenarios. Tanks were filled 25% ratios assess baffle height was adjusted based previous...

Along with developing high-speed craft technology, the planing hull is growing modifications for better performance. One such technology stepped hull, both single and double. Planing steps allows boat to run at a relatively low drag-lift ratio lower frictional resistance due reduced wetted area. In this study, was modified variations in position of double steps, which aimed determine effect first second step positions on total resistance, dynamic trim, sinkage generated by computational...

Abstract In this study, the study of water waves was carried out using one major mesh-free CFD i.e. Smoothed Particle Hydrodynamics (SPH). DualSPHysics ver 5.0 which is an open-source SPH solver based on Weakly Compressible (WCSPH) used to reproduce three dimension in large and medium numerical wave tanks (NWT). This analyses profiles accuracy for regular with period 1.15 second two NWT were used, i.e., 35 15 m. addition, advanced post-processing VisualSPHysics mimic real conditions. Single...

This study aimed to validate the single-phase and two-phase smoothed particle hydrodynamics (SPH) on sloshing in a tank. There have been many studies tanks based meshless methods, but few researchers used large number of particles because there is limitation total when using only CPUs. Additionally, investigated influence air phase tank SPH. In this study, dedicated experiment was conducted at National Research Institute Fishing Engineering prismatic with four-degrees-of-freedom forced...

The demand for liquid carriers, such as liquefied natural gas (LNG), has increased in recent years. One of the most common types LNG carriers is membrane type, which often built by a shipyard with prismatic tank shape. This carrier commonly known its effective ways to mitigate sloshing using baffle. Therefore, this study was performed evaluate vertical and T-shape baffles. conducted 25% 50% filling ratios because it deals nonlinear free-surface flow. Furthermore, smoothed particle...

Spray strips are deflectors added to the hull reduce Wetted Surface Area (WSA). The reduced WSA will decrease total ship drag caused by deflection of spray strip installation. research aimed predict function improve performance using Computational Fluid Dynamics (CFD). numerical approach in this study used Finite Volume Method (FVM) with RANS (Reynolds-averaged Navier–Stokes) equation solve fluid dynamics problems. VOF (Volume Fluid) was model water and air phases. results indicated that...

Abstract Shipping industries, one of the efficient modes freight transport for global trade, are now being forced to demonstrate environmental commitment reduce greenhouse gas emissions progressively. Stakeholders in maritime community have proposed various countermeasures and action plans, including applying new energy resources future development ship powers. This paper introduces a comprehensive review categorize pathways highlight core technological concepts, technical issues, current...

The patrol boat is one of the critical aspects for archipelago countries, such as Indonesia, to supervise and maintain sea border. Due rough conditions, could lose its stability due loss a self-righting roll moment in severe waves. One most challenging ensure sufficient during conditions. Another challenge design that has rolling extreme This paper examines an anti-capsize ship by improving with different deck houses height. condition described when experiences angle 170°. principal...

This paper is aimed to validate smoothed particle hydrodynamics (SPH) on the generation and propagation of water waves. It a classical problem in marine engineering but still important because there strong demand generate intended nonlinear waves predict complicated interactions between fixed/floating bodies, which indispensable for further ocean utilization development. A dedicated experiment was conducted large wave basin Kobe University equipped with piston-type wavemaker, at three depths...

Sloshing is one of challenging problem in the free surface flow, because dealing with large deformation fluid. The present paper was carried out numerical sloshing prismatic tank that resemble LNG membrane type carrier. Pressure sensor used to validate dynamic pressure low filling ratio tank. Forced oscillation motion sway f = 1.08 Hz and amplitude 6.52 mm. A single, double vertical baffles are reduce hydrodynamic force. baffle heigh water depth 0.9. meshless computational fluid dynamics...

Abstract Pitting corrosion is the most common, dangerous, and destructive type in marine offshore structures. This of can reduce strength ship plate, so investigating it using several numerical grounding scenarios needed to determine significant degradation structural plate. In this study, a finite element study was used evaluate influence pitting location on bottom plate simulation. simulated 14 different positions Finite explicit dynamic simulation LS Dyna software employed ship. The...

Akurasi dalam memprediksi hambatan kapal adalah salah satu aspek penting mendesain lambung kapal. Secara umum, dengan type planing lebih rumit daripada displacement. Planing hull memiliki karakteristik unik seperti trim, heave, hard-chine, Froude number tinggi dan dead-rise angle. Gaya hidrodinamik pada dominan gaya hidrostatik. Analisis numerik menggunakan Finite Volume Method (FVM) dipilih untuk menyelesaikan masalah hidrodinamik. Dalam penelitian ini, persamaan (RANS Reynolds-Averaged...

Computational Fluid Dynamics (CFD) is a numerical analysis used in solving problems related to water flow. Many methods have been created the application of CFD, one which Smoothed Particle Hydrodynamics (SPH). SPH meshless method where each fluid represented by particle. In this study, 3D simulation was carried out for phenomenon sloshing with roll motion prismatic, square, cylindrical and spherical tanks duration 28 seconds. The filling ratio at 25% addition vertical baffles horizontal...

The present study is to carry out a numerical sloshing using smoothed particle hydrodynamics (SPH) in the prismatic tank. Sloshing violent flow caused by resonance of fluid tank external oscillation. was used resemble membrane LNG type carrier. experiment carried three pressure sensors, camera high resolution, and four degrees freedom forced oscillation machine. In this study, filling ratio 25% reproduce low ratio. Only roll motion simulation. Roll directly imposing from displacement,...

Abstract The propeller was one of the main propulsors in ships that consumed a lot fuel due to viscous force acting ship. Therefore many studies have been carried out increase performance ship propellers. One ways is using Energy Saving Device (ESD) improve performance. ESD Propeller Boss Cap Fins (PBCF). PBCF used by reducing hub vortex during rotation. In this study, we compare before and after installation without changing dimensions. variations fins were made 0,1D, 0,2D, 0,3D with...

The sloshing phenomenon is one of the free surface flow that can endanger liquid cargo carriers such as ships. Sloshing defined resonance fluid inside a tank caused by external oscillation. When close to natural frequency it could Particle method has advantages be applied because dealing with surface. One particle methods Smoothed Hydrodynamics (SPH). In this study, compressible SPH was used result pressure oscillation, which exists effect density fluctuation nature weakly SPH. To reduce...

Sloshing is a phenomenon where the tank experiences an external oscillating motion due to interaction of fluid with tank. The most appropriate way prevent instability from sloshing movement add baffles or anti-sloshing. This paper was conducted 3D simulation roll on prismatic time 28 seconds. Vertical and Horizontal were used mitigate in ratio baffle height water depth 0.7, 0.8 0.9. Moreover, horizontal position 0.1, 0.2, 0.3, 0.4 respectively, filling 25%. numerical study carried out using...

Abstract Water wave propagation is one of the classical problems in free surface flow that involved water and air. There are a lot studies have been conducted on both experimental numerical methods. One method computational fluid dynamics (CFD), which divided into two major i.e. CFD mesh-based meshfree. In this paper, smoothed particle hydrodynamics (SPH) used to carry out study propagation. SPH mesh-free Lagrangian approach suitable for such as waves. Two-phase was reproduce long-distance...

This study discusses the inverted bow design on combatant hull form. Changes in shape of stem angle and flare are used as analytical parameters to investigate ship's performance. Ship resistance motion will be predicted using Computational Fluid Dynamics (CFD) approach Reynolds Averaged Navier Stokes (RANS) equation k-ε turbulence model. The volume fluid (VOF) method is applied simulate change free surface between water air an overset mesh technique. movement limited sinkage trim motions, so...

Kabupaten Batang terletak di pantai utara Jawa Tengah dimana wilayah pesisir kabupaten ini terdapat potensi yang dapat dikembangkan menjadi aset berharga bagi bangsa yaitu para pembuat kapal tradisional. Sebagian besar pengrajin kayu tradisional dalam pembangunan konstruksi tanpa melalui proses rancang bangun secara modern. Dalam pelaksanaannya, baik tipe ataupun bentuk dibangun, berdasarkan pengalaman kapal-kapal pernah dibuat sebelumnya dan perhitungan penggambaran terlebih dahulu,...

Batang which is located on the north coast of Central Java with an area 788.642 km 2 position district put economy a path island Java. Coastal region this district, make there potential that can be developed into valuable asset to nation i.e traditional shipbuilders. Karangasem one districts have for ship production In terms productivity shipyard,one shipbuilder CV. Laksana Abadi as shipyard in year 2000 capable producing ships totaling 18 units within period 12 months. not only but also...

AbstrakKapal Patroli merupakan kapal yang memiliki ukuran relatif kecil, namun kecepatan cukup tinggi. Bentuk kecil akan berpengaruh terhadap gerakan rolling kapal, sehingga menarik untuk dibahas secara mendalam pengaruh pemasangan bilge keel kapal. Penelitian ini menganalisis ditambah jumlahnya menjadi 2 pasang dan 3 efek agar dapat memperbaiki performa lebih baik. Model patroli telah didesain dianalisis menggunakan metode BEM (Boundary Element Method) terintegrasi mendapatkan nilai pada...