Wavelength fixing mechanism

The data is collected to establish the wavelength fixing mechanism for short-pitch rail corrugation. Average wavelengths are measured on each of the heavily corrugated rail track curves using a ruler. Train speeds are downloaded from a few locomotive black boxes. The speeds data is extracted into an excel spreadsheet. The blackbox downloads data every minute and captures Global Positioning System (GPS) coordinates for the location where the train speeds were captured. Together with train speeds, corrugation wavelengths are used to calculate corrugation frequencies for each track curve. The average corrugation frequencies were saved for correlation to a locomotive traction wheelset natural frequencies. Experimental Modal Analysis was conducted to obtain the point Frequency Response Functions (FRF) of the class D39200 locomotive wheelset. The wheelset resonance modes were obtained and a fundamental resonance mode at 108 Hz is found have a more closer correlation to corrugation frequencies for each track curve. The GPS coordinates were used on Google Earth Pro to view the terrain and gradients of the track curves. The blackbox data downloaded also recorded whether the train was in traction or braking during recording of the data, together with that information, the gradient on Google Earth Pro was used to determine the direction of the train. The excel spreadsheets named with locomotive numbers contain the GPS data downloaded in decimal form, whilst the files with a CSV format shows the GPS data that has been converted to degrees, minutes and seconds. A Finite Element Model was developed to validate the resonance modes of the traction wheelset and also to investigate the mode shapes of the wheels and axle on vibrational excitation. The axle and wheel drawings for the D39200 wheelset used for the model are attached. Modala Analysis was conducted on the rail to capture the vibration phase midspan between two sleepers. The vibration phase was captured for rail on FY and PY-type concrete sleepers; and also on steel sleepers. This exercise was done to investigate the correlation of the vibration phase of the wheels to that of the rail on different types of sleepers. Two excel files named "Rail on steel sleeper vs PY or FY type concrete sleeper". This data also has the captured vibration phase data for the wheels.