Garuda - Garba Rujukan Digital

Gorlov Water Turbine Application in Ambon, Kepulauan Maluku; A Hypothetical Project Wardhana, Wisnu; Rahayu, Zahra Aisyiyah; Rahmawati, Shade; Satrio, Dendy
International Journal of Offshore and Coastal Engineering (IJOCE) Vol 6, No 1 (2022)
Publisher : Pusat Publikasi Ilmiah Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j25800914.v6i1.14556

As energy demand increases, it must be balanced with sufficient energy sources to support the growth of Indonesia's electrification ratio. No exception with the development of energy demand and supply on Ambon, Maluku Islands. This study uses a Renewable Energy Power Plant, a water turbine that uses ocean currents from the flow path of an artificial canal plan in Ambon, Maluku Islands. The shape of the area is interesting things to make an artificial canal as a flow path for ocean currents from the different height at that location. Due to the height difference cannot be determined with certainty, in this study, the authors vary the height difference between the sea in the east and west, it's 1m to 5m. Current modelling uses a numerical approach using the Surface-Water Modeling System (SMS) 8.1 software simulation. Then the average current velocity in the canal in each height variation obtained. The experimental data from journal references are used in calculating the turbine torque for a full-scale afterwards adjusted to the current speed generated in each variation. The turbine with the greatest torque is selected, owned by the 4-blades Gorlov NACA0012 with 25% efficiency and 9.5m turbine diameter totalling 1 unit

Effect of Preheating Process and V Groove Type on the Tensile and Metallography Test of ASTM A53 with A36 Weld Joint Using FCAW Method Pratikno, Herman; Baredwan, Abdullah Husin; Dhanista, Wimala Lalitya
International Journal of Offshore and Coastal Engineering (IJOCE) Vol 6, No 2 (2022)
Publisher : Pusat Publikasi Ilmiah Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j25800914.v6i2.14769

Steel is a metal material that is often used in the maritime industry due to its availability and weldability. ASTM A53 steel is a low carbon steel commonly used for piping applications. ASTM A36 steel is a low carbon steel commonly used for offshore buildings. This study aims to determine the influence of preheat temperature and V groove type on bend resistance of A53 and A36 weld joint using FCAW (Flux Cored Arc Welding) method. The preheat temperature used are 100°C and 150°C with groove type variations used were single V groove and double V groove. The type of protective gas used is 100% CO2. The results of tensile strength test showed that in the welding process in this study, specimen with preheat temperature of 150°C and double V-Groove shape has the strongest tensile strength, with HAZ width of 3.91 mm, ferrite phase percentage of 58.08%, and pearlite phase percentage of 41.92%.

Tension Leg Rectangular Fish Cage Motion Analysis in Regular and Random Waves Riyanto, Raditya Danu; Wibowo, Yuni Ari; Ramzi, Mochammad
International Journal of Offshore and Coastal Engineering (IJOCE) Vol 6, No 2 (2022)
Publisher : Pusat Publikasi Ilmiah Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j25800914.v6i2.14774

This paper uses an analytical method to examine the motion of a Tension Leg Fish Cage (TLFC) in regular and random waves. TLFC is a conceptual design of a fish cage based on the Tension Leg Platform (TLP) working principle that is usually used in deep water offshore oil and gas exploration. The idea of providing a safe environment to combine ecotourism and fish farming in a single platform led us to perform an analytical calculation to assess the possibility of using the TLP concept in fish farming. A preliminary conceptual design of TLFC using an HDPE floater with steel cable tendon is presented. The analytical calculation of the response amplitude operator for surge and heave motion is presented using linear airy wave theory with head seas encountering angle. This paper also presents the calculation of TLFC surge and heave motion under random wave loads. The random wave spectra used in this paper are JONSWAP and ISSC spectra. The result shows that the surge and heave motion response of TLFC is relatively smalland, therefore, can be analyzed further with more detailed consideration. It is admitted that HDPE is a brittle material that cannot sustain any long period of constant tension. Hence the optimum tendon-floater connection for the structure is subject to further research.

Micro Wave Energy Farming on Slender Pile Structure Husna, Faliha; Rahmawati, Shade; Armono, Haryo Dwito
International Journal of Offshore and Coastal Engineering (IJOCE) Vol 6, No 2 (2022)
Publisher : Pusat Publikasi Ilmiah Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j25800914.v6i2.14770

The development of renewable energy technology has mostly beenfocused on macro-sized farming models. Recent studies have explored the benefits of micro wave energy to support offshore sensor networks. This paper discusses the viability of micro ocean energy farming of wave energy on slender pile structure through piezoelectric converters. Case study was obtained using Tuban environmental data from the year 2004-2009. Significant wave height and period were used to generate wave forces on slender pile and converted to electrical energy using simple piezoelectric converter equations. The resulting wave force on a 0.03m thick piezoelectric plate generates voltage of 0.6 Volt.

Hydrodynamic Performance Analysis of Vertical Axis Water Turbine (VAWT) Gorlov Type With Hydrofoil Thickness and Inclination Angle Variables using Computational Fluid Dynamics (CFD) Approaches Wardhana, Wisnu; Rahmawati, Shade; Satrio, Dendy; Nurliana, Annisa
International Journal of Offshore and Coastal Engineering (IJOCE) Vol 6, No 2 (2022)
Publisher : Pusat Publikasi Ilmiah Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j25800914.v6i2.14771

The issue of renewable and eco-friendly energy has become the focus of research in several countries to encourage eco-friendly alternative energy. One of them is by using turbines to produce electrical energy. Vertical Axis Water Turbine (VAWT) can be an exciting research object because it has various advantages. VAWT has a simpler structure, can move at relatively slow currents and is famous for its tendency to move regardless of the water flowdirections. In this study, the experimental turbine from secondary data numerically simulates using the Computational Fluid Dynamics (CFD) method with the help of ANSYS V18.1 software. The Gorlov turbine model is manufactured in 3 dimensions under steady-state flow conditions. Validation is carried out after obtained numerical results with the mean error rate being less than 10%. The variables in this research are the thickness of hydrofoil using NACA 0010, NACA 0016, NACA 0020, and variations in inclination angle of the blade for 25. After comparing the simulation results in the form of torque values is done, it is shown that the best turbine performance is given by water turbine using NACA 0016 with 60 and 60 of inclination angle.

Saddle Strength Analysis on Jacket Structure During Roll Up Procedures in Fabrication Phase Defriana, Nabila; Handayanu, Handayanu; Syahroni, Nur
International Journal of Offshore and Coastal Engineering (IJOCE) Vol 6, No 2 (2022)
Publisher : Pusat Publikasi Ilmiah Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j25800914.v6i2.14772

Offshore platform is a structure that serves as a well drilling facility to explore, extract, store and process petroleum and gas located under the seabed. There are several phases in theconstruction of offshore structures (fixed jacket platform) from preparation to construction. Fabrication phase is the earliest stage in the manufacture of a fixed offshore platform (jacketstructure) which is carried out by the fabricator. One of the procedures at the fabrication phase is roll up procedure. In this final project research, an analysis will be carried out regarding the configuration of the rigging, crane, and sadle support used in the jacket structure during roll up procedure. After the analysis of jacket structure modeling using the SACS software, the results of rigging configuration can be obtained, which were the slingsspesifications used to connect the structure with cranes, with sling diameter of 2.75 inch and SWL value of 64 MT. As for the sling used to connect the jacket with winch has a diameter of 1.5 inch snd SWL value of 18 MT. Furthermore, the cranes used have a capacity of 75 and 78 MT, respectively. In the load analysis of the jacket structure, it was found that saddle support received the largest reaction when the jacket was at an 80-degree slope with the largest reaction value of 102.74 MT. In the saddle support local analysis, the result of maximum equivalent von-mises stress obtained was 43,486 MPa, with the saddle allowable stress of 345 Mpa, therefore the UC value of 0.24 can be obtained.

Experimental Study of Electrode Variation Effect on Connection Strength for Underwater Welding Wicaksono, Benedictus Arif; Syahroni, Nur; Mulyadi, Yeyes
International Journal of Offshore and Coastal Engineering (IJOCE) Vol 6, No 2 (2022)
Publisher : Pusat Publikasi Ilmiah Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j25800914.v6i2.14773

SMAW welding has various electrodes that can be used in underwater welding. This study will analyze the influence of electrode type on mechanical properties and the influence ofwelding position on the mechanical properties of joints for underwater welding. This experiment results show that the E7016 electrode pull test has a superior value than the E6013 and E7018 electrodes; when compared between E6013 and E7016, it is reasonable if the E7016 is stronger than E6013 and the frequency level is higher than E6013 even if it already uses a different amper. However, if the E7016 electrode compared to the E7018 is still superior to the E7016 electrode using the same voltage and amper. In addition, the results of macro test observations show that welding using the E7018 electrode has lower porosity levels than E7016 electrodes, while with the same experiment results, the tensile strength of the E7016 is superior to the E7018. So that the power value of E7016 electrodes can be superior to E7018 in this experiment is not only based on porosity that occurs but also slag and imperfect penetration also determines the strength of welding results by using E7016 electrodes.

The Effect of Addition of Mangrove Avicennia Marina Extract on The Biofouling Activity to Epoxy Coating Aisyah, Dwi Maharani; Pratikno, Herman; Titah, Harmin Sulistiyaning
International Journal of Offshore and Coastal Engineering (IJOCE) Vol 6, No 2 (2022)
Publisher : Pusat Publikasi Ilmiah Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j25800914.v6i2.15609

Biofouling is one of the problems related to construction maintenance in industrial developments in the maritime construction sector because biofouling adhesion can affect construction productivity. This problem can be overcome by coating using natural-based paints to reduce the ecological impact that will occur. This study aims to determine the effect of the addition of Avicennia marina mangrove extract as an anti-fouling compound mixed with epoxy paint. This research was conducted by mixing Avicennia marina mangrove extract with epoxy paint. Then the alloy is applied as a coating on the ASTM A36 steel specimen. Furthermore, the test was carried out by immersing the specimen in a solution containing Littorina littorea as a biofouling biota. The average results of the biofouling affixing activity test with the addition of mangrove extract concentrations of 0%, 10%, 20%, and 30% were respectively 24.0 gr, 20.5 gr, 13.5 gr, and 6 gr. This test shows that the more the addition of mangrove extracts, the smaller the adhering activity of biofouling to the specimen.

Design Unmanned Minesweeper Catamaran as a Tool to Make a Safer Marine Environmental Using Analytical Methods Kusuma, Cahya; Mulyono, Radityo Dimas; Kusdiana, Wawan; Syaifi, Muhammad; indiaryanto, Mahendra
International Journal of Offshore and Coastal Engineering (IJOCE) Vol 7, No 1 (2023)
Publisher : Pusat Publikasi Ilmiah Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j25800914.v7i1.15527

After the war is over, the sea mine layer must be neutralized because if the mine explodes, it will cause environmental damage and the death of marine life. Minefields with very shallow water are difficult to clear using a minehunter. Mining in shallow sediment-covered areas is still hazardous, especially if the area is bridges, shore dredging, ports, or shipping lanes. This study designed the hull of the Unmanned Mines Sweeper (UMS) Catamaran, which towing side scan sonar so that it could double function as a mine-like detection and a survey vessel for seabed environmental conditions in very shallow areas. UMS design with analysis method using Maxsurf Modeler Advanced V21.13 software. Line plan design and general settings using AutoCAD software with data obtained from models designed using Maxsurf software. Total resistance value using Maxsurf Resistance Advanced V21.13 software. UMS uses a Catamaran design with an LoA of 4.823 meters, LwL of 4.177 m, and a width of 2.24 m. The ship has a high draft of 0.498 with a displacement of 1.557 tons. The results of the resistance analysis obtained Rt of 404.94 N. The drive system uses an electric motor that can provide endurance for 6 hours.

Experience in Oceanographic Surveys for Designing 100 kW Tidal Current Energy Conversion Systems Mukhtasor, Mukhtasor; Rasgianti, Rasgianti; Junianto, S; Lestari, S; Rahmawati, S; Erwandi, Erwandi; Ikhwani, H; Pratikto, W A; Nugraha, A D; Simaremare, A A; Ruly, Ruly
International Journal of Offshore and Coastal Engineering (IJOCE) Vol 7, No 1 (2023)
Publisher : Pusat Publikasi Ilmiah Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j25800914.v7i1.16913

Nowadays tidal current energy conversion system (TCECS) is being developed with a capacity of 100 kW for Indonesian waters. The design process is based on the results of field measurements, i.e., ocean currents, tides, ocean waves, and bathymetry. This paper aims to explain the experiences when collecting oceanography data in a potential site for TCECS. The survey method is that the equipment placed on the seabed will emit signals that can record flow and wave data according to the desired time and depth. The survey process, especially for the tidal current energy application, requires good preparation so as not to fail. The results of this paper explain the challenges and highlight the steps. These are technical, environmental, and survey permits. The technical aspects are tool stability, buoyancy effects, visualization tools with an underwater camera system, seawater brightness, and sedimentation. Environmental aspects are big waves, strong currents, and weather. The survey permit aspects are destruction and conservation area. Therefore, before the survey, safety procedures or documents must be made in the form of HIRA (Hazard Identification and Risk Analysis). The experiences of this survey are a novelty consideration for other surveyors in the tidal current energy aspect.

Home Page

OAI Link

Editorial Team

Contact

Reviewer

Google Scholar

Contact Name
-

Contact Email
-

Phone
-

Journal Mail Official
-

Editorial Address
-

Location
Kota surabaya,

Jawa timur

INDONESIA

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Home Page

OAI Link

Editorial Team

Contact

Reviewer

Google Scholar

Contact Name -

Contact Email -

Phone -

Journal Mail Official -

Editorial Address -

Location Kota surabaya, Jawa timur INDONESIA

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Contact Name
-

Contact Email
-

Phone
-

Journal Mail Official
-

Editorial Address
-

Location
Kota surabaya,

Jawa timur

INDONESIA