Optimasi Desain Trailing Edge Splitter untuk Mengurangi Turbulensi dan Pressure Drop pada Exhaust Silencer Turbin Gas Menggunakan Metode CFD dan Bayesian Optimization

Authors

  • Ibrahim Basalamah Program Studi Teknik Mesin, Fakultas Teknik, Universitas Negeri Malang, Indonesia
  • Ahmad Atif Fikri Program Studi Teknik Mesin, Fakultas Teknik, Universitas Negeri Malang, Indonesia
  • Willyanto Anggono Program Studi Teknik Mesin, Fakultas Teknologi Industri, Universitas Kristen Petra, Indonesia
  • Dani Harmanto School of Engineering and Sustainable Development, De Montfort University, United Kingdom

DOI:

https://doi.org/10.9744/jtm.23.2.102-113

Keywords:

gas turbine, exhaust silencer, trailing edge optimization, computational fluid dynamics, Bayesian Optimization

Abstract

Gas turbines are widely used in modern power generation due to their high efficiency and flexibility. However, using exhaust silencers in exhaust gas systems can increase back pressure, reducing overall turbine performance. The aerodynamic behavior of the splitter inside the exhaust silencer, especially at the trailing edge, significantly affects pressure drop and turbulence intensity. This study aims to optimize the trailing edge geometry of a GE Frame 6FA exhaust silencer splitter using a combination of computational fluid dynamics (CFD) and Bayesian optimization (BO). CFD simulations were conducted in ANSYS Fluent using a poly-hexcore mesh, while the optimization employed a Gaussian process (GP) surrogate model with an expected improvement (EI) acquisition function. Seven trailing edge angles (5°–20°) were evaluated to observe the aerodynamic trade-off between pressure drop and turbulent kinetic energy (TKE). The optimal configuration was found at 13.9°, yielding a TKE of 0.43 J/kg and a pressure drop of 18.38 Pa, well below the industrial allowable pressure drop limit of 34 Pa. The results confirm that the BO-GP framework effectively reduces computational cost while achieving a more aerodynamically balanced silencer design.

Author Biographies

  • Ibrahim Basalamah, Program Studi Teknik Mesin, Fakultas Teknik, Universitas Negeri Malang, Indonesia

    Undergraduate Mechanical Engineering Student at Universitas Negeri Malang

  • Ahmad Atif Fikri, Program Studi Teknik Mesin, Fakultas Teknik, Universitas Negeri Malang, Indonesia

    Lecturer at the Department of Mechanical Engineering, Faculty of Engineering, Universitas Negeri Malang. 

  • Willyanto Anggono, Program Studi Teknik Mesin, Fakultas Teknologi Industri, Universitas Kristen Petra, Indonesia

    Professor at the Department of Mechanical Engineering, Faculty of Industrial Technology, Petra Christian University. Research interests include combustion engineering, product design, finite element methods, and materials engineering.

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Published

2026-10-29

Issue

Vol. 23 No. 2 (2026): OCTOBER 2026 (SINTA 3)

Section

Articles

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Copyright (c) 2026 Ibrahim Basalamah, Ahmad Atif Fikri, Willyanto Anggono, Dani Harmanto

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Jurnal Teknik Mesin is publihed by the Mechanical Engineering Department, Petra Christian University, Indonesia


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