Abstract: With setting different gas pressure in pipe, the pressure loss coefficient of vortex street flowmeter is investigated in Fluid Lab, school of Electrical Engineering and Automation, Tianjin University, China. Results show that the change of gas pressure in pipe can affect the pressure loss coefficient by processing a mass of experimental data. When gas pressure in pipe is increased from 0.1 Mpa to 1.1 Mpa, the pressure loss coefficient will decrease with the increasing of the gas pressure and the amplitude of variation is 7%. This changing regularity is studied and the equation which expresses the relation between the pressure loss coefficient and gas pressure in pipe is given.

Key words: Differential pressure cell, Gas pressure, Pressure loss, Pressure loss coefficient, Vortex street flowmeter