Taking into consideration the main assumption regarding operation of the top foil, i.e., its ability to measure both temperature and strain fields, adequate shapes of the three bump foils are assured. Multifunctional top foil is a measuring component that requires a number of wires allowing for electrical connections. Hence, considerable material removals are made in the bump foil, also to provide the space for thermocouple spots and strain gauges. It was however confirmed during design process that the adapted geometry of the bump foils still provided demanded stiffness.
Temperature and strain measurement points are localized circumferentially in three rows. Various localization patterns are used for thermocouples and strain gauges to prevent from their overlap. Detailed angular positions of these sensors are presented below.
