Multivariable Vortex Flowmeter for nitrogen is a vortex air flowmeter. The Multivariable Vortex Flowmeter operates as follows: Under specific active conditions, a part of the kinetic energy of the fluid is transformed into fluid vibration, and its vibration frequency has a definite proportional relationship with the flow rate (flow ). Flowmeters based on this principle are called fluid vibration flowmeters. At present, there are three types of fluid vibration flowmeters: vortex flowmeter, precession (vortex precession) flowmeter and jet flowmeter. Fluid vibration flowmeter has the following characteristics: 1) The output is pulse frequency, and its frequency is proportional to the actual volume flow of the measured fluid, which is not affected by fluid composition, density, pressure and temperature; 2) Wide measuring range, the general range can reach more than 10:1; 3) The accuracy is above average level; 4) No moving parts, high reli…