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Flood Rescue Boat as One of the Alternatives in Indonesia Waterways Meitha Soetardjo; Ede Mehta Wardhana; Ahmad Bisri
Journal of Ocean, Mechanical and Aerospace -science and engineering- Vol 63 No 3 (2019): Journal of Ocean, Mechanical and Aerospace -science and engineering- (JOMAse)
Publisher : International Society of Ocean, Mechanical and Aerospace -scientists and engineers- (ISOMAse)

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1127.456 KB) | DOI: 10.36842/jomase.v63i3.127

Abstract

Flooding is the most frequent disaster that hit Indonesia, especially in big cities with poor urban planning. Infrastructure damage has occurred, the fatalities which are likely to occur, both during floods and after floods. So far, the fatalities caused by floods are very difficult to control and even tend to increase. This condition is getting worse with the lack of facilities that support the evacuation process of flood victims. The aim of the study was to design a lifeboat that was able to evacuate flood victims and be able to overcome other problems that might arise when the evacuation process runs more efficiently. By collecting data from several agencies related to flood mitigation problems, interviews with experts, as well as several other references, it is hoped that relevant data can be collected, which can provide solutions to the problems faced. The stages of the research included the creation of concepts and the design of a hull shape that was adjusted for a flood rescue boat, a boat with high stability. By using of the Maxsurf V.8.5 and Hydromax V.8.5 program, it is expected that the design process and calculation of boat stability can be done more quickly and accurately. The results of research for several areas affected by floods, the existence of a rescue boat as a means to evacuate victims is urgently needed. So that the provision of a multifunctional flood rescue boat is the perfect solution to overcome this problem. To carry out this function, the stability of the rescue boat flood is one of the factors that must be considered so that the evacuation process can be carried out safely
Optimizing Ocean Energy Harvesting: The Significance of Natural Frequency in Piezoelectric Generator Device Electrical Output Ede Mehta Wardhana; Meitha Soetardjo; Semin Semin; Agoes Santoso; Sutopo Purwono Fitri
International Journal of Marine Engineering Innovation and Research Vol 8, No 4 (2023)
Publisher : Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j25481479.v8i4.19258

Abstract

This study explores the significance of the natural frequency parameter in enhancing the electrical performance of a piezoelectric generator device, mainly when deployed in ocean energy harvesting. While natural energy harvesting aims to establish affordable and sustainable renewable energy sources, piezoelectric devices capitalize on the inherent piezoelectric effect derived from natural movements. Despite the abundance of constant natural movements in the Earth's environment, the application of piezoelectric devices in ocean energy remains relatively understudied. The experimental setup involves a cantilever-designed piezoelectric device made from polyvinylidene fluoride (PVDF). The study investigates the relationships between vibration frequency, initial distance, and electrical output. Findings indicate that higher setup parameters may lead to increased electrical output, but the relationship is not linear. Notably, the resonance between the vibration frequency and the device's natural frequency emerges as a critical factor in optimizing electrical performance. Detailed experimentation, visualized through figures and graphs, demonstrates the nuanced interplay of setup parameters and electrical output. The study emphasizes that the initial distance, while important, does not singularly determine the device's electrical performance. It challenges conventional beliefs by showcasing that piezoelectric devices can operate efficiently in tight spaces. Furthermore, the study delves into the non-linear relationship between vibration frequency and electrical output. Examining natural and resonant frequencies reveals that resonance occurs most prominently at the device's natural frequency, emphasizing the importance of precise tuning for optimal performance. The findings offer valuable insights for the strategic deployment of piezoelectric technology in ocean energy harvesting, paving the way for more efficient and effective devices in real-world conditions
Critical Chain Project Management and Buffer Planning: Study Case at Security Accommodation Vessel Construction Bella Puji Darma Samodra; Agoes Santoso; Ede Mehta Wardhana
International Journal of Marine Engineering Innovation and Research Vol. 10 No. 1 (2025)
Publisher : Department of Marine Engineering, Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j25481479.v10i1.4748

Abstract

Shipbuilding projects frequently encounter delays and cost overruns as a result of unpredictability in the construction process. This paper aims to explore the potential of Critical Chain Project Management (CCPM) and buffer planning to enhance scheduling in complex shipbuilding project. The research approach involves a case study of a Security Accommodation Vessel (SAV) construction project, complemented by expert interviews which were conducted to assess the risks and uncertainties affecting activity durations. The buffer sizes were then calculated using the Root Square Error Method (RSEM). Qualitative data was gathered through interviews with the expert to identify and assess potential risks and uncertainties impacting activity durations. This qualitative insight informed the application of the RSEM to determine appropriate buffer sizes. The planned project duration was reduced from 790 days to 678 days, representing a 14,5% improvement. The study focuses on the planning phase of CCPM and demonstrates the potential of combining CCPM, buffer planning, and expert input to create more reliable schedules for complex shipbuilding projects like SAV construction.
Optimization of The Slope Angle of a Submerged Piezoelectric on a Laboratory Scale Ede Mehta Wardhana; Danang Jawara Ditya; Farhan Ilyasa
International Journal of Marine Engineering Innovation and Research Vol. 9 No. 4 (2024)
Publisher : Department of Marine Engineering, Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j25481479.v9i4.4896

Abstract

Piezoelectrics are materials that can produce electrical voltage when subjected to mechanical stress. This unique property makes piezoelectrics widely used in various applications, such as sensors, actuators, and transducers. One important factor that can influence piezoelectric performance is the tilt angle. The tilt angle is defined as the angle between the piezoelectric surface and the direction of the applied force. This research aims to optimize the tilt angle of immersed piezoelectrics on a laboratory scale. Using the experimental method, this research was carried out using piezoelectric PVDF. Piezoelectric PVDF was chosen because it has good piezoelectric properties and is easy to obtain. Experiments were carried out by applying mechanical force to the piezoelectric PVDF with various tilt angles. Experimental results show that the optimal tilt angle for submerged piezoelectric PVDF is 90 degrees with a value of 7.46196 milliVolts at a flow speed of 1.2m/s. At this tilt angle, the piezoelectric PVDF produces the highest electrical voltage. The results of this study indicate that the optimal tilt angle for sunken piezoelectrics is 90 degrees. This could provide a basis for the development of more efficient and high-performance piezoelectric designs.
Analysis of Output Voltage in Contact Separation Triboelectric Nanogenerator with Frequency Variation and its Suitability in Ships: A Numerical Calculation-Based Study Ede Mehta Wardhana; Agoes Ahmad Masroeri; Brivo Rafanki
International Journal of Marine Engineering Innovation and Research Vol. 9 No. 3 (2024)
Publisher : Department of Marine Engineering, Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j25481479.v9i3.4925

Abstract

Triboelectric Nanogenerator (TENG) is an innovative technology that harnesses the triboelectrification phenomenon to generate electricity through the Contact Separation mode, where two materials with triboelectric properties interact. TENG can generate electricity at low frequencies. In the context of ship engine vibrations, the application of TENG with the Contact Separation mode can convert mechanical vibration energy from vibrations generated in the ship engine room into additional electrical power sources. The principle of TENG operation focuses on changes in triboelectric charge during the contact, separation, and compression processes. This study uses parameters commonly encountered in ships, namely low-frequency vibrations, as well as limitations imposed by classifications and regulations on these vibrations. Parameters used to analyze suitable modes for application in ships vary, namely frequencies ranging from 1 to 30 Hz and displacement distances ranging from 0.5 to 2 mm with intervals of 0.5 mm, resulting in voltages ranging from 0.01 to 1.55 V. After obtaining suitable modes, this study will match the modes for application on ships with a frequency of 50 Hz and displacement distances varied from 7 to 25 mm using FEP and Silicone materials, resulting in voltages ranging from 13.20 to 249.20 V. The results of this research can provide guidance for the development of TENG technology on ship engines to enhance energy efficiency and sustainability in the maritime sector.
Optimizing Ocean Energy Harvesting: The Significance of Natural Frequency in Piezoelectric Generator Device Electrical Output Ede Mehta Wardhana; Meitha Soetardjo; Semin; Agoes Santoso; Sutopo Purwono Fitri
International Journal of Marine Engineering Innovation and Research Vol. 8 No. 4 (2023)
Publisher : Department of Marine Engineering, Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j25481479.v8i4.5090

Abstract

This study explores the significance of the natural frequency parameter in enhancing the electrical performance of a piezoelectric generator device, mainly when deployed in ocean energy harvesting. While natural energy harvesting aims to establish affordable and sustainable renewable energy sources, piezoelectric devices capitalize on the inherent piezoelectric effect derived from natural movements. Despite the abundance of constant natural movements in the Earth's environment, the application of piezoelectric devices in ocean energy remains relatively understudied. The experimental setup involves a cantilever-designed piezoelectric device made from polyvinylidene fluoride (PVDF). The study investigates the relationships between vibration frequency, initial distance, and electrical output. Findings indicate that higher setup parameters may lead to increased electrical output, but the relationship is not linear. Notably, the resonance between the vibration frequency and the device's natural frequency emerges as a critical factor in optimizing electrical performance. Detailed experimentation, visualized through figures and graphs, demonstrates the nuanced interplay of setup parameters and electrical output. The study emphasizes that the initial distance, while important, does not singularly determine the device's electrical performance. It challenges conventional beliefs by showcasing that piezoelectric devices can operate efficiently in tight spaces. Furthermore, the study delves into the non-linear relationship between vibration frequency and electrical output. Examining natural and resonant frequencies reveals that resonance occurs most prominently at the device's natural frequency, emphasizing the importance of precise tuning for optimal performance. The findings offer valuable insights for the strategic deployment of piezoelectric technology in ocean energy harvesting, paving the way for more efficient and effective devices in real-world conditions.
Flashpoint and Flame Spread Analysis of Material Coconut Fiber (Cocus Nucifera) Using Chemical Treatment of Alkali NaOH as a Sound Absorber Material in Ship Alam Baheramsyah; Ede Mehta Wardhana; Nasa Dityas Fariz Pradani
International Journal of Marine Engineering Innovation and Research Vol. 6 No. 1 (2021)
Publisher : Department of Marine Engineering, Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j25481479.v6i1.5855

Abstract

The use of sound absorbers on many ships made from glass wool. Glass wool has a negative impact on health, which can irritate the skin and disrupt the respiratory system. Therefore, it is necessary to have an alternative sound insulation material that is eco-friendly which has capabilities comparable to glass wool, and can also be used as heat insulation on ships. These alternative ingredients are materials from natural fiber. This research made sound absorbers using coconut fiber by soaking fiber into an alkali NaOH solution. Materials are selected based on density, economic value, and ease in the manufacturing process. The sound absorbers are modified using coconut fiber which is given a soaking treatment of alkaline NaOH solution and distilled water with a percentage of 15%. Soaking aims to remove lignin content and improve the mechanical properties of coconut fiber. In this research, 9 variations were made with different compositions. Tests are based on ASTM E84 to determine the flashpoint value and the safe flame spread on the ship. From the test results, it was found that coconut coir material was given a soaking treatment of alkaline NaOH solution with a percentage of 15% for 2 hours with a density of 0.3 gr/cm3 and thickness 30 mm and using a polyurethane adhesive. The time to reach the flashpoint is 20.45 seconds and the average temperature of flame spread is low when compared to other specimens including glass wool. The conclusion obtained is that the sound absorbers are safe when used on a ship.
Coolbox Design Modification for Traditional Fishing Vessel Using Sengon Wood Sawdust and Potassium Hydroxide-Soaked Coconut Coir Ede Mehta Wardhana; Alam Baheramsyah; Hilmy Yassar
International Journal of Marine Engineering Innovation and Research Vol. 5 No. 1 (2020)
Publisher : Department of Marine Engineering, Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j25481479.v5i1.6020

Abstract

This research modified coolbox by mixing sengon wood sawdust and potassium hydroxide-soaked cocofiber. By considering its composition, potassium hydroxide content, and soaking duration, this research was done to find the optimum amount of those three variables to make the best insulator. The best insulator was chosen based on its thermal conductivity, density, and economic value, and the easiness in the making. From the experiment, the chosen composition consists of 30% sengon wood sawdust and 70% potassium hydroxide-soaked cocofiber with content of 15% and soaking duration of 2 hours. With thermal conductivity of 0,352W/mK, density of 0,303gram/cm3, and specimen production cost of Rp607,41, this material was used for composition reference in the making of the coolbox. The experiment of coolbox lasted for 35 hours with 71 temperature data retrievals. The coolbox experiment used 500 gram tuna fish and 2500 gram ice as cooler. The result showed that the lowest temperature for ice inside coolbox was 0,3°C, the lowest temperature of fish was 5°C, and the lowest temperature in coolbox chamber is 17°C. With the ratio of 1:5 for fish and ice, the coolbox insulation using sengon wood sawdust and potassium hydroxide-soaked cocofiber was able to maintain fish temperature below 20°C for 27,5 hours. Meanwhile, the styrofoam coolbox was able to maintain fish with the same condition for 35 hours.
Utilization of Mixture of Teak Wood Sawdust and Bagasse Fiber using Treatment of Fiber Variations and Alkali NaOH Immersion as A Refrigerator Insulation Material Alam aheramsyah; Ede Mehta Wardhana; Achmad Taufik Rendi Kisserah
International Journal of Marine Engineering Innovation and Research Vol. 4 No. 2 (2019)
Publisher : Department of Marine Engineering, Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j25481479.v4i2.6030

Abstract

This research modified the insulation of coolbox material by utilizing a mixture of teak wood sawdust (Tectona grandis L.f.) and previously immersed bagasse fiber (Saccharum officinarum) into an alkali NaOH solution to improve the mechanical properties of the fiber and reduce the value of material thermal conductivity. The most optimal test and analysis results were obtained by composing 50% teak wood sawdust with 50% of previously immersed bagasse fiber in an alkali NaOH solution at a level of 15%. The obtained conductivity value is 0.2907 W / mK, the density is 0.4901 gram / cm3. Experiments on changes in temperature of ice, fish, and coolbox chamber as well as experiments on the duration of fish preservation in the coolbox with variations in the composition of straight fibers have better performance compared to the variation of random fiber which is able to preserve fish for 34 hours with minimum temperature of 0, 2 ° C. For fishing duration of two days, coolbox with a variety of straight fiber has almost the same performance as coolbox made from styrofoam and has the potential to replace styrofoam because it is more environmentally friendly.
Analysis of Gottingen 428 Airfoil Turbine Propeller Design with Computational Fluid Dynamics Method on Gravitational Water Vortex Power Plant Ede Mehta Wardhana; Agoes Santoso; Asep Rahmat Ramdani
International Journal of Marine Engineering Innovation and Research Vol. 3 No. 3 (2019)
Publisher : Department of Marine Engineering, Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j25481479.v3i3.6055

Abstract

Along with technological development and the increase in human population, the electricity needs are increasing every year. However, 94% of power plant in Indonesia still using fossil fuels that are pollutant and non-renewable. In addition, NASA said that the earth's temperature had risen by 1°C since 1880 and the current carbon dioxide level was the highest in the last 650,000 years. Therefore, Indonesia need to improve, in fact Indonesia is one of the highest emission contributors in the world. Indonesia is not yet 100% electrified, there are still 2,519 villages without electricity. Gravitational Water Vortex Power Plant (GWVPP) which is a micro hydro-power plant may answer the problem, because it is an easy renewable energy to be made and utilized in the NIZ (not interconnected zones) region. This study will examine the changes in the number and shape of the blade, as well as the length of the chord, to know the effect on turbine power so that it can produce higher efficiency at GWVPP. Propeller turbine with a Gottingen 428 airfoil analyzed using Computational Fluid Dynamics (CFD) method. The results show that the number of blades and the length of the chord is inversely proportional to the efficiency of the turbine, and the shape of blade is more efficient when it’s twisted.