Glossary

What are transonic airfoils, and what is the active clearance control? Check out our technical dictionary and find out more about engine technology terms – from active clearance control to velocity triangle.

Thermal barrier coatings Thermal efficiency Thermal spraying Thrust class Thrust-to-weight ratio Total stage efficiency Transonic airfoils Turbine Turbine engine Turbofan engine Turbojet engine Turboprop engine Turboshaft engine

Transonic airfoils

Transonic airfoils feature areas where the medium flows at supersonic velocity. With transonic compressor cascades this applies to the outlet flow. The pressure is increased not only by deceleration and deflection but also by a gas-dynamic shock in the duct between the airfoils. With turbines the flow towards the transonic airfoils is slower than the velocity of sound but the medium leaves the cascade at supersonic velocity. Transonic airfoils are indispensable for engine components with high power density. Calculation and manufacture of such airfoils is complicated as a high degree of accuracy is required.