Article Per Year (5 Year)
p-Index From 2021 - 2026
0.61
P-Index
This Author published in this journals
All Journal Journal of Engineering and Technological Sciences Dental Journal (Majalah Kedokteran Gigi) Jurnal Teknologi Dirgantara Indonesian Journal of Aerospace
Lavi Rizki Zuhal
Faculty Of Mechanical And Aerospace Engineering, Institut Teknologi Bandung, Bandung, Indonesia
Aerospace Engineering Astronomy Chemical Engineering, Chemistry & Bioengineering Computer Science & IT Dentistry Engineering Mechanical Engineering Physics

Published : 7 Documents Claim Missing Document
Claim Missing Document
Check
Articles

Found 7 Documents
Search

 1 
Core Spreading Vortex Method for Simulating 3D Flows Around Bluff Bodies Zuhal, Lavi Rizki; Dung, Duong V.; Sepnov, Alex J.; Muhammad, Hari
Journal of Engineering and Technological Sciences Vol 46, No 4 (2014)
Publisher : ITB Journal Publisher, LPPM ITB

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1641.249 KB) | DOI: 10.5614/j.eng.technol.sci.2014.46.4.7

Abstract

This paper presents the development of core spreading vortex element method, which is a mesh-free method, for simulating 3D viscous flow over bluff bodies. The developed method simulates external flow around complex geometry by tracking local velocities and vorticities of particles introduced within the fluid domain. The viscous effect is modeled using core spreading method coupled with the splitting spatial adaption scheme, and a smoothing interpolation scheme for overlapping issue and population control, respectively. The particle’s velocity is calculated using Biot-Savart formulation. To accelerate computation, Fast Multipole Method (FMM) is employed. The solver is validated, for both unbounded and bounded flows at low Reynolds numbers, using a number of benchmark problems. For unbounded case, simulation of the collision of two vortex rings was performed. To test the performance of the method in simulating bounded flow problem, simulation of flow around a sphere was carried out. The results are found to be in good agreement with those reported in literatures and also simulations using other diffusion model.
Core Spreading Vortex Method for Simulating 3D Flows Around Bluff Bodies Lavi Rizki Zuhal; Duong V. Dung; Alex J. Sepnov; Hari Muhammad
Journal of Engineering and Technological Sciences Vol. 46 No. 4 (2014)
Publisher : Institute for Research and Community Services, Institut Teknologi Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.5614/j.eng.technol.sci.2014.46.4.7

Abstract

This paper presents the development of core spreading vortex element method, which is a mesh-free method, for simulating 3D viscous flow over bluff bodies. The developed method simulates external flow around complex geometry by tracking local velocities and vorticities of particles introduced within the fluid domain. The viscous effect is modeled using core spreading method coupled with the splitting spatial adaption scheme, and a smoothing interpolation scheme for overlapping issue and population control, respectively. The particle's velocity is calculated using Biot-Savart formulation. To accelerate computation, Fast Multipole Method (FMM) is employed. The solver is validated, for both unbounded and bounded flows at low Reynolds numbers, using a number of benchmark problems. For unbounded case, simulation of the collision of two vortex rings was performed. To test the performance of the method in simulating bounded flow problem, simulation of flow around a sphere was carried out. The results are found to be in good agreement with those reported in literatures and also simulations using other diffusion model.
SIMULASI ALIRAN FLUIDA DUA DIMENSI TANPA MEMBUTUHKAN KISI-KISI DENGAN MENGGUNAKAN METODE VORTEKS. STUDI KASUS ALIRAN DI SEKITAR SILINDER DAN PELAT DATAR YANG BERGERAK TRANSLASI (MESHLESS SIMULATION AROUND TWO DIMENSIONAL FLOW USING VORTEX METHOD. CASES STUDY: FLOW AROUND CYLINDER AND MOVING FLAT PLATE WITH TRANSLATIONAL MOTION) Akhmad Farid Widodo; Lavi Rizki Zuhal; Hari Muhammad
Jurnal Teknologi Dirgantara Vol.11 No.1 Juni 2013
Publisher : National Institute of Aeronautics and Space - LAPAN

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Makalah ini membahas algoritma metode vorteks yang merupakan metode numerik simulasi dinamika fluida tanpa membutuhkan kisi-kisi. Metode vorteks memodelkan aliran fluida dengan pendekatan Lagrangian dimana elemen fluida didiskritisasi menjadi bola-bola partikel yang bergerak mengikuti aliran fluida. Untuk menguji hasil simulasi metode vorteks, dilakukan simulasi aliran yang bergerak secara tiba-tiba disekitar silinder dan aliran disekitar pelat datar yang bergerak secara translasi. Hasil simulasi memberikan hasil yang cukup baik dibandingkan dengan pengukuran eksperimental yang ditunjukkan dengan perbandingan pola distribusi vortisitas.Kata Kunci: Metode vorteks, Simulasi tanpa kisi-kisi, Aliran di sekitar pelat datar, Aliran di sekitar silinder
METODA COROTATIONAL BEAM 2D UNTUK ANALISIS STATIK STRUKTUR NONLINIER GEOMETRIK Novi Andria; Lavi Rizki Zuhal; Leonardo Gunawan; Hari Muhammad
Jurnal Teknologi Dirgantara Vol. 17 No. 1 Juni 2019
Publisher : National Institute of Aeronautics and Space - LAPAN

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30536/j.jtd.2019.v17.a3117

Abstract

Makalah ini membahas sebuah metoda corotational beam dua dimensi (CBM 2D) yang dapat digunakan untuk analisis statik struktur yang nonlinier secara geometri. Kombinasi antara formulasi corotational beam dan Euler-Bernouli beam Theory (EBT) membuat implementasi numerik metoda ini menjadi sangat sederhana dengan beban komputasi yang rendah sehingga sangat praktis untuk diaplikasikan. Akurasi dan efisiensi metoda ini terverifikasi melalui beberapa uji numerik yang dilakukan pada beberapa model uji yang terdapat pada literatur. Metoda ini pun mampu memberikan hasil yang akurat untuk kasus extensible beam dan struktur beam yang dibebani follower load. Hasil penelitian ini memverifikasi validitas, efisiensi, dan kepraktisan dari metoda yang dikembangkan.
Discretization Corrected Particle Strength Exchange for Steady State Linear Elasticity Christopher Adnel; Lavi Rizki Zuhal
Journal of Engineering and Technological Sciences Vol. 54 No. 4 (2022)
Publisher : Institute for Research and Community Services, Institut Teknologi Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.5614/j.eng.technol.sci.2022.54.4.3

Abstract

Discretization corrected particle strength exchange (DC PSE) is a particle based spatial differential operator designed to solve meshless continuum mechanics problems. DC PSE is a spatial gradient operator that can discretize a computational domain with randomly distributed particles, provided that each particle has enough neighboring particles. In contrast, conventional methods such as the standard finite difference method require the computational domain to be discretized into a Cartesian grid. In linear elasticity simulations, especially steady state cases, this domain is mostly discretized using mesh-based methods such as finite element. However, while particle methods such as smoothed particle hydrodynamics (SPH) have been widely applied to solve dynamic elasticity problems, they have rarely been used in steady state simulations. In this study, a DC PSE operator was used to solve steady linear elasticity problems in a two-dimensional domain. The result of the DC PSE numerical simulation was compared to numerical results, empirical formula results, and results from conventional commercial finite element software, respectively.
Visualizing the velocity fields and fluid behavior of a solution using artificial intelligence during EndoActivator activation Harry Huiz Peeters; Elvira Theola Judith; Faber Yosua Silitonga; Lavi Rizki Zuhal
Dental Journal Vol. 55 No. 3 (2022): September 2022
Publisher : Faculty of Dental Medicine, Universitas Airlangga https://fkg.unair.ac.id/en

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20473/j.djmkg.v55.i3.p125-129

Abstract

Background: Electrical devices driven sonically have been found in several studies to be effective to clean root canals but the effect of the EndoActivator irrigant activation flow behavior on cleaning efficacy is not completely understood. Purpose: The study aimed to provide an initial understanding of flow behavior and velocity field generation during the irrigant activation process by EndoActivator using artificial intelligence (AI). Methods: A straight glass model was filled with a solution containing 17% EDTA. Meanwhile, a medium activator tip with 22-mm polymer noncutting #25, 0.04 file driven by an electrical sonic hand-piece at 190 Hz (highest level) was used to induce velocity field to produce micro-bubbles. The physical mechanisms involved were recorded using a Miro 320S highspeed imaging system, the hydrodynamic responses were recorded, and analyzed using a motion estimation program supported by LiteFlowNet (AI). Results: The rapid fluid flow was visualized clearly in the model when it was activated by an EndoActivator tip. It was also observed that the distal end of the EndoActivator tip generated a near-wall high gradient velocity apically in all directions of the oscillation. Conclusion: The analysis showed that the proposed motion estimation program, supported by LiteFlowNet (AI), was able to capture velocity magnitude estimation of a non-PIV experiment and visualize the bubbles generated in the solution.
A Corotational Formulation For Geometrically Nonlinear Dynamics of 2D Flexible Beams Andria, Novi; Zuhal, Lavi Rizki; Muhammad, Hari; Gunawan, Leonardo
Indonesian Journal of Aerospace Vol. 22 No. 2 (2024): Indonesian Journal Of Aerospace
Publisher : BRIN Publishing

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.55981/ijoa.2024.8949

Abstract

A simple and efficient 2D corotational formulation for dynamic analysis of geometrically nonlinear flexible beam is presented in this paper. The corotational approach can easily facilitate the evaluation of internal elactic forces by introducing an element frame to separate rigid body motion and the deformational part. In the present study, the Euler-Bernoulli beam models with simple geometric stiffness matrix is employed and Newmark’s implicit time-stepping scheme with iterative predictor-corrector algorithm is adopted. The validity and efficiency of the present corotational formulation are verified by simulating three numerical examples. Despite its simple numerical implementation, simulation results confirms that the proposed formulation is highly accurate and efficient in simulating flexible beams undergoing large deformation.
Co-Authors Akhmad Farid Widodo Alex J. Sepnov Alex J. Sepnov Christopher Adnel Duong V. Dung Duong V. Dung Elvira Theola Judith Faber Yosua Silitonga Hari Muhammad Harry Huiz Peeters Leonardo Gunawan Leonardo Gunawan, Leonardo Novi Andria Novi Andria, Novi