Design, realisation and performance evaluation of a high accuracywake drag measurement device for CIRA transonic wind tunnel

摘要

A new wake rake for drag measurement in the CIRA transonic windtunnel PT-1 has been designed and realised for 2D airfoilcharacterisation. Accuracy requirement was indicated as ±1 countin transonic regime, to be satisfied at all angle of attack conditionswithout needs for repositioning the device, and to be achieved with nomore than 64 total pressure measurement position; this last requirementstemmed from the very high cost of the data acquisition systemelectronic pressure scanners. Besides, blockage minimisation, ability tomeasure wave drag, possibility to measure wake losses at differentdistances from profile trailing edge were required. The selectedinterface with wind tunnel test section was the arc sector model supportsystem, already equipped with passages for tubes routing to the plenum,and an easy and quick installation was required to enhance productivity.This work presents the process leading to technical specifications, aswell as system design and some design details. Some test results arepresented, that show how requirements have been fulfilled