Amirkabir University of Technology Amirkabir Journal of Mechanical Engineering 2008-6032 56 12 2025 02 19 Performance Analysis of Non-Reacting Flow of a Single and Double Swirler in a Microchamber Using Numerical Simulation Method Performance Analysis of Non-Reacting Flow of a Single and Double Swirler in a Microchamber Using Numerical Simulation Method 1663 1690 5723 10.22060/mej.2025.23813.7816 FA Esmaeil Yadollahi Afra Department of Aerospace, Faculty of New Sciences and Technologies, Semnan University, Semnan, Iran Elyas Lekzian Faculty of Aerospace Engineering,, Semnan University, Semnan, Iran 0000-0001-9287-5127 Journal Article 2025 01 06 Creating swirl flow in combustion chambers is a method to enhance combustion efficiency. One way to achieve this is through the use of a swirler, which generates swirling flow using angled vanes. This swirling flow leads to better mixing and subsequently improves the combustion process. Researchers have explored various methods to increase the mixing of the flow passing through the swirler, with one of the most challenging and significant methods being changes in swirler geometry. Using a double swirler is a novel approach in swirler design. This paper examines the interaction between inner and outer swirlers, identifies recirculation zones, and studies changes in swirl number. The comparison between single and double swirlers in this paper shows that a single swirler creates a larger recirculation zone and higher swirl intensity, contributing to flame stability. Additionally, four new recirculation zones are formed after the double swirler, which also enhances flame stability. The use of a double swirler increases turbulent kinetic energy by up to 75% and turbulence intensity by up to 60%, resulting in better fuel-air mixing and achieving a uniform axial velocity distribution in a shorter distance from the combustion chamber. Creating swirl flow in combustion chambers is a method to enhance combustion efficiency. One way to achieve this is through the use of a swirler, which generates swirling flow using angled vanes. This swirling flow leads to better mixing and subsequently improves the combustion process. Researchers have explored various methods to increase the mixing of the flow passing through the swirler, with one of the most challenging and significant methods being changes in swirler geometry. Using a double swirler is a novel approach in swirler design. This paper examines the interaction between inner and outer swirlers, identifies recirculation zones, and studies changes in swirl number. The comparison between single and double swirlers in this paper shows that a single swirler creates a larger recirculation zone and higher swirl intensity, contributing to flame stability. Additionally, four new recirculation zones are formed after the double swirler, which also enhances flame stability. The use of a double swirler increases turbulent kinetic energy by up to 75% and turbulence intensity by up to 60%, resulting in better fuel-air mixing and achieving a uniform axial velocity distribution in a shorter distance from the combustion chamber. https://mej.aut.ac.ir/article_5723_d94fd74dcde1aa553be72c1006578b23.pdf