unsteady heat transfer problems

Example: heating up of a hollow turbine blade

Background of the calculation was the question, what happens to turbine blades, if the temperature in the combustion chamber of a gas turbine increases for a short time. The calculations have been performed with the CFD-code TASCFLOW. First, a steady state solution was computed. The velocity of the flow was 500 m/s. The temperature of the fluid was 800°C. The temperature at the base of the blade was fixed at 350°C.

Starting from the steady-state solution a transient calculation was performed. At t=0, the flow temperature was set to 1000°C.

The picture shows the temperature on the surface of the blade for different times. It takes about 1.4 s to heat up the hottest part of the blade (see cross at the tip of the leading edge) from 800°C to 900°C.