Abstract: The measurement of a flowmeter needs to be in a relatively stable environment, and flow fluctuation produced by a pipeline in actual measurement has an impact on measurement results of the flowmeter. In order to investigate the influence of different flow fluctuations on the measurement results of the pipeline, a blade-type flow fluctuation generator is designed in this paper, which drives a butterfly valve to swing back and forth through a motor to form the flow fluctuation in the pipeline. The generator can change the oscillation frequency and swing angle of the motor to produce different flow fluctuations and imitate the flow fluctuations that may occur in a water flow system. Our experiments have demonstrated that the flow fluctuation generated by the blade-type flow fluctuation generator can propagate along upstream and downstream of the pipeline, and the flow fluctuation will also varies as the oscillation frequency and swing angle of the generator are changed simultaneously or individually.

Key words: flow fluctuation generator, pressure characteristic, frequency conversion, amplitude of variation