Flow induced pulsation in piping are serious concern in refrigeration installations where noise and vibrations are critical factors. This report takes an insight look into the possible ways to minimise the noise and vibration due to pulsations. A modification of the discharge piping was done to reduce the noise produced by pressure pulsation in oil flooded screw compressor. It gets complex while trying to deduce the natural frequency of complicated piping with branches and bends. FEMLAB was used as simulation software. Reflection of waveform in piping masks the real amplitude of the pressure pulsation. A method based on signal processing was employed to decompose the incident and reflected wave.