Dilution Holes

Dilution holes are strategically positioned apertures in combustion chamber liners designed to introduce secondary air into the primary combustion zone. These holes control flame temperature, reduce thermal gradients, prevent overheating of liner walls, and minimize NOx emissions by creating a more uniform temperature profile. They are critical for maintaining optimal combustion efficiency, extending component lifespan, and meeting environmental regulations in gas turbines, industrial furnaces, and aerospace propulsion systems.

Dilution holes operate on the principle of staged combustion and thermal management. During operation, high-temperature combustion gases flow through the liner. Secondary air is injected through these holes at specific angles and velocities, mixing with hot gases to lower local temperatures, dilute fuel-rich zones, and create controlled recirculation patterns. This process stabilizes the flame, reduces peak temperatures that cause thermal stress, and ensures complete fuel oxidation while preventing flame impingement on liner surfaces.