How might the spectrum change if the pumping system is affected by turbulence?

When a pumping system experiences turbulence, it generates a more complex flow within the pump. This turbulence can lead to the modulation of the vibration signal. As a result, the frequency spectrum may exhibit a "hump" of noise in areas below the running speed. This noise is typically caused by the irregular and fluctuating flow patterns created by turbulence, which can introduce a spectrum of lower frequency components.

These lower frequency components appear as increased amplitudes or a "hump" on the spectrum, indicating that the turbulence is influencing the overall vibration characteristics at these frequencies. The turbulence disrupts the smooth operation of the pump, causing variations in pressure and giving rise to noise that might not be present under normal operating conditions. Therefore, this change in spectrum indicates that the system is experiencing non-ideal conditions due to turbulence.