Article Per Year (5 Year)
p-Index From 2021 - 2026
3.993
P-Index
This Author published in this journals
All Journal Jurnal Pendidikan Vokasi Jurnal Pendidikan Teknologi dan Kejuruan VOLT : Jurnal Ilmiah Pendidikan Teknik Elektro Jurnal Sains dan Teknologi: Jurnal Keilmuan dan Aplikasi Teknologi Industri JURNAL PENDIDIKAN TAMBUSAI MOTIVECTION : Journal of Mechanical, Electrical and Industrial Engineering Suluah Bendang: Jurnal Ilmiah Pengabdian Kepada Masyarakat Teknomekanik Jurnal Aerasi Jurnal Vokasi Mekanika Journal of Engineering Researcher and Lecturer Venus: Jurnal Publikasi Rumpun Ilmu Teknik
Nabawi, Rahmat Azis
Department Of Mecahnical Engineering, Universitas Negeri Padang, INDONESIA
Humanities Automotive Engineering Chemical Engineering, Chemistry & Bioengineering Civil Engineering, Building, Construction & Architecture Computer Science & IT Control & Systems Engineering Education Electrical & Electronics Engineering Engineering Industrial & Manufacturing Engineering Mechanical Engineering Social Sciences Other

Published : 39 Documents Claim Missing Document
Claim Missing Document
Check
Articles

Found 3 Documents
Search
Journal : Teknomekanik

 1 
Stability Study of Flat Hull Ship for Fishing Tourism Nabawi, Rahmat Azis; Syahril, Syahril; Salmat, Salmat
Teknomekanik Vol. 3 No. 2 (2020): Regular Issue
Publisher : Universitas Negeri Padang

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (205.328 KB) | DOI: 10.24036/teknomekanik.v3i2.9272

Abstract

The availability of boats is needed to develop fishing tourism. Most of the boats used so far generally use fishing boats made of woodcut in the forest, so this can damage the environment and cause natural disasters. Ships using a flat plate hull made of steel can be a substitute for wooden ships. This study aims to test the stability of a flat plate vessel designed for fishing boats. The ship stability test was carried out using a computer simulation method using Maxsurf Stability software. The ship stability criteria refer to the International Maritime Organization code A.749 (18), Ch 3-design criteria applicable to all ships. The ship stability analysis was carried out on two variations of the load case. The value of GZ at A h 300, A h 400 and A h 300 - A h 400 for load case 1 and 2 are greater than the minimum standards determined by IMO. The maximum GZ value at load case 1 occurs at an angle of 400 and at load case 2 at an angle of 60.90. The GM value in load case 1 is 0.609 meters and in load case 2 is 0.485 meters. Based on the results of the tests that have been carried out, it can be denied that the flatboat design model for fishing tourism meets the criteria set by the International Maritime Organization.
Loading-dependent mechanical performance of alkali-treated areca nut husk fiber reinforced polyester composites modified with Uncaria gambir extract Nabawi, Rahmat Azis; Syahril, Syahril; Abral, Hairul
Teknomekanik Vol. 8 No. 2 (2025): Regular Issue
Publisher : Universitas Negeri Padang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24036/teknomekanik.v8i2.52472

Abstract

Natural fiber-reinforced polymer composites often experience mechanical performance limitations due to weak interfacial bonds between hydrophilic fibers and hydrophobic matrices. This study experimentally examined the effect of alkali treatment and modification using Uncaria gambir extract (UGE) on the mechanical properties and interface morphology of polyester composites reinforced with areca nut husk fiber (ANHF). Four composite configurations were prepared with a constant fiber weight fraction of 40 wt.% after alkali treatment using 6% NaOH for 24 hours, while the remaining 2 wt.% UGE was selectively applied as a fiber surface treatment, matrix additive, or a combination of both. Tensile and flexural properties were evaluated in accordance with ASTM standards, while interface morphology was examined using scanning electron microscopy (SEM). The results showed that alkali-treated composites without UGE addition had the highest tensile strength, which was attributed to increased fiber surface roughness and mechanical interlocking mechanisms. Conversely, fiber surface modification using UGE significantly increased flexural strength, indicating better stress distribution under flexural loading due to increased interface continuity. However, the addition of UGE to the matrix caused a decrease in tensile strength, which was thought to be related to a reduction in matrix stiffness. SEM observations confirm the presence of distinct interface morphology differences according to the treatment applied. These findings indicate that UGE serves primarily as a bio-based interfacial modifier, enhancing flexural performance, while its effectiveness is strongly governed by the mechanical loading mode.
Hydrodynamic optimization of a Sweptback Stern Foil for resistance reduction in flat-hull ships: A CFD-based extension of the Hull Vane concept Nabawi, Rahmat Azis; Syahri, Budi; Alfana, Yogi Dian; Fernandez, Donny
Teknomekanik Vol. 9 No. 1 (2026): Regular Issue
Publisher : Universitas Negeri Padang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24036/teknomekanik.v9i1.54872

Abstract

Flat-hull ships are known to have higher resistance than streamlined hulls. Although the Hull Vane® concept has been proven effective as a stern-mounted energy-saving device through pressure-field modification and stern-wave interaction, most previous studies have focused on straight-foil configurations (straight planform). The effect of planform shape optimization, particularly the sweptback configuration, on the hydrodynamic performance of flat-hull ships is limited in the literature. This study modifies the geometry of a Hull Vane® into a sweptback stern foil and evaluates its performance using Computational Fluid Dynamics simulations. The results show that a 15° sweptback angle yields the greatest reduction in total drag. Velocity contour analysis shows a narrower wake and a more uniform velocity-gradient distribution in the stern area for the 15° swept-back stern-foil configuration compared to other configurations. Meanwhile, the turbulence length distribution shows a tendency toward reduced intensity of large-scale turbulent structures behind the ship, indicating improved wake-flow characteristics. The identified drag reduction mechanism primarily stems from improved pressure recovery and modified pressure distribution in the stern area, which is consistent with the working principle of Hull Vane®. Optimizing the sweptback planform geometry yields more efficient flow interaction than the straight-foil configuration. These findings indicate that planform optimization is an important design parameter in the development of stern foils to improve the hydrodynamic efficiency of medium-to high-speed commercial vessels.
Co-Authors Abral, Hairul Aditia, Jefri Agung Pradana Putra Ahmad Sabirin Ahmad Sabirin Aldio, M. Fikhri Alwifari, M. Qari Ambiyar, Ambiyar Ambyar Ambyar Aminuyati Aprizal Saputra Arafat, Andril Arwizet Arwizet, Arwizet Arya Azis Zulhendrik Aulia, Ihsanul Budi Syahri Delima Yanti Sari Donny Fernandez Eko Indrawan Enjelita Enjelita Fadhil Naufan Fadillah, Egi Fahmi Rizal Fahrezi, Muhammad Shadiq Fauza, Anna Niska Febri Prasetya Fikriyyah Hilmy Ardana Fitra, Rizki Ganefri . Hendra Firdaus Hendra Irawan Hendri Nurdin Hendri Sawir, Hendri Husnul Fiqri Irzal Irzal Irzal Irzal Joko Suprianto Joko Suprianto Junil Adri Khairuni Delfi Anisa Muhamad Thaufiq Pinat Mulianti Mulyadi, Haris Shiddiq Musytari Rahmat Nasty, Aulia zulkarnaen Nelvi Erizon Nizwardi Jalinus Nofri Helmi Nurdin Hendri Permana, Kaesarion Rahman Preti, Agia Kulkarni Primawati Primawati, Primawati purwantono purwantono Purwantono, Purwantono Putra, Firza Fernanda Rahmat Rahmat Ravika Milya Refdinal Refdinal Rifelino Rifelino Rispendra, Rispendra Rodesri Mulyadi Salmat Salmat Salmat Salmat Salmat Salmat Salmat, Salmat Santika, Tiara Sasma Susanti Satria Sanurdi Sigit Dwi Lesmana Sukardi Sukardi Syahril Syahril Syahril Syahril Syahril Syahril Wahyu Ananda Putra Wahyudi Dwi Putra Wulansari, Rizky Ema Yaumal Arbi Yogi Dian Alfana Yufrizal A Zainal Abadi Zofa, Thifal Nefri Zuanda Maulana Nasution