OPTO-ELECTRONIC METHOD FOR WIND TUNNEL MODEL ALIGNMENT.

IN THE PAST, VERTICAL ALIGNMENT HAS BEEN ACCOMPLISHED USINGA SPRING-LOADED MECHANICAL TOUCHWIRE. THIS APPROACH PROVIDED A PARTIAL SOLUTION TO THE ALIGNMENT PROBLEM BUT HAD THE FOLLOWING SHORTCOMINGS: LOADING OF THE STORE BALANCE AT CONTACT, DISTURBANCE OF THE AIRFLOW IN THE VICINITY OF THE TOUCHWIRE, AND THE INABILITY TO PROVIDE POSITION INFORMATION IN THREE DIMENSIONS. THE DEVELOPMENT OF A NUMBER OF SMALL NONCONTACTING ALIGNMENT SENSORS OFFERS ATTRACTIVE SOLUTIONS TO THE MODEL ALIGNMENT PROBLEM, AND THE APPLICATION OF SEVERAL OF THESE SENSORS HAS BEEN EXPLORED. THE SENSORS CONSIDERED ARE OPTICAL SENSORS, CAPACITANCE PROBES, EDDY CURRENT AND MAGNETICRELUCTANCE PROBES, MAGNETICALLY COUPLED SENSORS, AND POSITION-SENSING DIODES. THIS PAPER DESCRIBES THE APPLICATION OF OPTICAL SENSORS AND FIBER OPTICS INCLUDING DESCRIPTIONS AND RESULTS OF LABORATORY TESTS.