We have built an experimental apparatus for the investigation of thermal-fatigue occurring in stagnant branch-lines departing from main coolant lines of nuclear power plants. 

Particle Image Velocimetry (PIV) and other high-resolution instrumentation is used to gather high-fidelity data.

A complex flow structure appears in the stagnant branch line as a consequence of the main pipe flow.


Particle Image Velocimetry (PIV) and Laser Doppler Velocimetry (LDV) is used to perform high-resolution measurements of the flow field in the isolated branch line. As expected, increasing penetration depth with increasing main line flow-rate is observed. A cork-screw flow structure upstream of the penetration boundary is also seen.