ICE ACCRETION AND PERSISTENCE AT UNMANNED SITES

THIS PROPOSAL CONCERNS THE DESIGN, FABRICATION AND TESTING OF A VERSATILE INSTRUMENT FOR THE CONTINUOUS COLLECTION AND WEIGHING OF ICE ACCRETION IN REMOTE REGIONS. THE INSTRUMENT USES A LOAD CELL THAT WILL MEASURE ICE LOAD ACCUMULATIONS ON A VERTICALLY ORIENTATED MAST ADAPTED TO IT. THE LOAD CELL BASE STRUCTURE IS PROTECTED FROM ICE ACCRETIONS THAT WOULD BRIDGE TO THE COLLECTION MAST AND FOUL MEASUREMENTS BY A ELASTOMERIC DE-ICER BOOT. THE DESIGN INCORPORATES A METHOD FOR MOMENTARILY LIFTING THE MAST LOAD FROM THE LOD CELL TO ESTABLISH A ZERO CALIBRATION BEFORE ICE WEIGHT MEASUREMENT. THIS WOULD OCCUR EACH TIME THE DE-ICER BOOT IS ACTUATED. CAPACITY SENSORS LOCATED UNDER THE DE-ICER BOOT ARE PROPOSED AS AN ICE DETECTOR TO MONITOR ICE ACCRETIONS ON THE LOAD CELL BASE. IF PROPERLY LOCATED THESE SENSORS MAY AUGMENT THE MAST WEIGHT MEASUREMENTS WITH THE AZIMUTHAL DIRECTION OF THE OCCURRING ACCRETIONS TO SAVE ENERGY, DETERMINE DE-ICER BOOT ACTUATION PERIODS. THE INSTRUMENT WILL EMPLOY ELECTRONICS AND COMPUTER HARDWARE, TOGETHER WITH SOFTWARE PROGRAMS TO MANAGE THE INSTRUMENT, STORE AND RELAY DATA.