Optimization of Airblast Injectors Arrangement for Uniform Temperature Distribution in Gas Turbine Combustion Chamber: An Experimental Study

Chenarani, Hamid; Sajadmanesh, Seyed Morteza; Agahi, Amir; Moradkhani, Afshin; Shahnazari, Mohammad Reza

doi:10.22075/jhmtr.2025.37134.1691

Optimization of Airblast Injectors Arrangement for Uniform Temperature Distribution in Gas Turbine Combustion Chamber: An Experimental Study

Articles in Press

Document Type : Full Length Research Article

Authors

Hamid Chenarani ¹

Seyed Morteza Sajadmanesh ²

Amir Agahi ³

Afshin Moradkhani ⁴

Mohammad Reza Shahnazari ¹

¹ Department of Mechanical Engineering, K. N. Toosi University of Technology, Mollasadra Ave., Pardis, Tehran, 1991943344, Iran

² b Faculty of Mechanical and Energy Engineering, Shahid Beheshti University, Bahar Blvd., Hakimieh, Tehran, 16589-53571, Iran

³ Department of Mechanical Engineering, Amirkabir University of Technology, No. 350, Hafez Ave, Valiasr Square, Tehran, 1591634311, Iran

⁴ Faculty of Material Science and Engineering, Islamic Azad University, Moazen Blvd., Karaj, 3149968111, Iran

10.22075/jhmtr.2025.37134.1691

Abstract

An experimental investigation was conducted to enhance gas turbine combustion chamber efficiency by eliminating hot spots, stabilizing operation, and achieving uniform temperature distribution. The effects of gas-to-liquid ratio (GLR) on spray characteristics of an industrial airblast injector were studied using the Particle Droplet Image Analysis (PDIA) technique. At GLR = 3.8, the minimum Sauter Mean Diameter (SMD) reached 235 µm at 4 cm from the injector tip centerline. Axial and radial distributions of SMD revealed that higher GLRs result in finer atomization, with a reduction of up to 22% in average droplet size compared to low GLR cases. The spray cone angle varied between 92° and 96°, influencing particle dispersion and chamber coverage. Injector rearrangement based on spray pattern, SMD, and cone angle achieved a 3% reduction in average turbine outlet temperature and significantly improved temperature uniformity, as confirmed by six thermocouple measurements. These results demonstrate that optimized injector configuration enhances combustion performance and thermal efficiency in gas turbines.

Keywords

Sauter mean diameter

Industrial injector

Air-blast atomizer

Particle droplet image analysis

Gas turbine

Subjects