High Sensitive Micro Flexible Thermal Sensor for Flow Separation Measurements on Airfoil

A high sensitive micro flexible thermal sensor was developed to investigate the boundary layer separation and transition over NACA 0012 airfoil. The temperature coefficient of resistance (TCR) of 5100ppm/K was achieved after thermal annealing. The transition location and separation angle of attack (AOA) were identified successfully by the thermal sensors. Wind tunnel tests indicated that the transition region propagated upward to the leading edge as the increased AOA and Reynolds number. The static stall angle was decreased from 13° at Re
_c
=0.87×10
⁶
to 12° at Re
_c
=1.67×10
⁶
. Surface pressure distributions and lift coefficient curves were also obtained to validate the thermal sensors measurements.