STUDI KARAKTERISTIK REDAMAN PELAT PLEXIGLAS PERSEGI PANJANG DENGAN GETARAN HARMONIK

• Main Author: Sjahmanto (NIM :233, Mohammad
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/5368
• Institution: Institut Teknologi Bandung

<b>Abstract</b><p align=\"justify\">Experiment on the rectangular plate plexiglas of 400x40x5 mm using clamp and supporting system for obtaining a damping ratio ? and a loss factor ? was made. The system was vibrated by the excitation frequency from 20 to 180 Hz and measured from 3 different position with the different time. <br /> <p align=\"justify\">Measuring and data acquisition was applied recording method with computer program and manual method or direct reading from the Digital Multimeter. The method of calculation or analysis was used a logarithmic decrement, half power bandwidth and dynamic- magnification factor. <br /> <p align=\"justify\">Analysis result showed that with logarithmic decrement method, the damping ratio was decreasing from 10-13% to 4-6% and the maximum value appeared at a resonance. Calculated loss factor was obtained between 0.1 and 0.5 following the increasing frequency of excitation. When observation was made on the measuring point, it was obtained that the vrl^,- of damping ratio for measuring point closed to the clamp was higher than the value of that for other measuring points. <br /> <p align=\"justify\">With the based on half power bandwidth method and dynamic-magnification factor for the observation at a resonance range, the value of damping ratio was obtained about 25-40%, while analysis of loss factor was obtained about 0.5 up to 0.8. <br /> <p align=\"justify\">For observation with based on the measuring point, the value of damping ratio at the middle position was obtained higher then that was obtained at other positions.