Finite Element Analysis of Structural Integrity and Fatigue Life of Char Removal System in High-Temperature Gasification

Nina K. Supriatna (Research Center for Energy Conversion Technology, Badan Riset dan Inovasi Nasional)
Agung T. Kuncoro (Department of Mechanical Engineering, Universitas Pamulang)
Bayu A. Saputro (Department of Automotive and Mechanical Engineering, Universitas Muhammadiyah Magelang)
Muhammad Iksanudin (Department of Mechanical Engineering, Universitas Gajah Mada)
Silviana Simbolon (Department of Mechanical Engineering, Universitas Pamulang)
Muhammad Yunus (Research Center for Nuclear Reactor Technology, Badan Riset dan Inovasi Nasional)
Prima Zuldian (Research Center for Energy Conversion Technology, Badan Riset dan Inovasi Nasional)
Agus Kismanto (Research Center for Fuel Technology, Badan Riset dan Inovasi Nasional)
Maulana Arifin (Research Center for Energy Conversion Technology, Badan Riset dan Inovasi Nasional)
Raden I. Purawiardi (Research Center for Energy Conversion Technology, Badan Riset dan Inovasi Nasional)

Indonesian Journal of Energy
Vol. 9 No. 2 (2026): Indonesian Journal of Energy

Biomass gasification is a crucial technology for sustainable energy conversion; however, its continuous operation and overall efficiency are heavily dependent on the reliable extraction of solid by-products. This study investigates the structural integrity and fatigue life of a char removal system used in high-temperature biomass gasification. The system operates under severe thermo-mechanical conditions, including elevated temperatures and varying mechanical loads, which may lead to structural degradation and failure. A Finite Element Analysis (FEA) approach using ANSYS was employed to evaluate the performance of ASTM A36 steel under mechanical loads of 100 kg, 150 kg, and 200 kg, combined with thermal conditions of 800 °C, 1000 °C, and 1200 °C. Key parameters analyzed include equivalent stress, elastic strain, total deformation, safety factor, and fatigue life. The results indicate that while temperature variations have minimal influence on peak stress values, they significantly affect the distribution of strain and deformation due to material stiffness degradation. In contrast, mechanical loading has a dominant impact on structural performance, leading to increased stress, deformation, and reduced safety factors. Fatigue analysis reveals that while the structure maintains a theoretical infinite design life of 1 × 10? cycles across all loads, the minimum fatigue safety factor drops significantly from 2.92 at 100 kg to 1.46 at 200 kg. In conclusion, ASTM A36 steel is structurally adequate and can safely withstand the applied thermo-mechanical loads without premature fatigue failure. However, the reduced safety margins under elevated mechanical loads highlight the critical need for load control and targeted geometric reinforcements at structural joints to ensure long-term reliability. To ensure long-term reliability and operational safety in biomass gasification systems, it is imperative to implement targeted geometric reinforcements at connection points or substitute the standard carbon steel with high-temperature-resistant alloys.