AIRCRAFT TIRE/WHEEL INTERFACE-LOAD MEASUREMENT

IN LATE 1986, WRDC/FIEVA INITIATED AN IN-HOUSE PROGRAM TO INVESTIGATE EXPERIMENTAL AND ANALYTICAL METHODS FOR AIRCRAFT-WHEEL-LIFE ESTIMATION AND VERIFICATION. AS PARTIAL FULFILLMENT OF THIS PROGRAM, STRUCTURAL MODELS OF TIRES AND A NEW STOCHASTIC CRACK GROWTH MODEL FOR THE WHEEL FRACTURE BEHAVIOR ARE BEING DEVELOPED. TO COMPLEMENT THESE RESEARCH EFFORTS A TIRE-WHEEL INTERFACE MODEL THAT YIELDS A DESCRIPTION OF THE WHEEL FLANGE AND BEADSEAT LOADS IS REQUIRED. PRESENTLY, THE BOUNDARY CONDITIONS AT THE TIRE-WHEEL INTERFACE ARE UNKNOWN. THE OBJECTIVE OF THIS RESEARCH PROPOSAL IS TO INVESTIGATE THE FEASIBILITY OF DEVELOPING A METHODOLOGY FOR ACCURATELY MEASURING THE LOAD DISTRIBUTION AT THE TIRE/WHEEL INTERFACE. A VARIETY OF COMMERCIALLY AVAILABLE PRODUCTS INCLUDING CONDUCTIVE RUBBER, FERRITE FLUID, PIEZOELECTRIC CRYSTALS AND CAPACITIVE DEVICES WILL BE STUDIED FOR USE IN A TOTALLY NEW INSTRUMENTATION DEVICE. THE LOADS MEASURED WITH THE PROPOSED DEVICE WILL BE USED IN EXISTING FINITE-ELEMENT MODELS OF AIRCRAFT WHEELS TO EVALUATE THE WHEEL'S COMPLETE STRUCTURAL RESPONSE TO THESE LOADS.