It can be considered from five aspects, which are flow meter performance, fluid characteristics, installation conditions, environmental conditions and economic factors. The detailed factors of the five aspects are as follows:
- Instrument performance: accuracy, repeatability, linearity, range, flow range, signal output characteristics, response time, pressure loss, etc.
- Fluid characteristics: temperature, pressure, density, viscosity, chemical corrosion, abrasion, scaling, miscibility, phase change, electrical conductivity, sound velocity, thermal conductivity, specific heat capacity, isentropic index;
- Installation conditions: pipeline layout direction, flow direction, length of straight pipe section on upstream and downstream side of detection parts, pipe diameter, maintenance space, power supply, grounding, auxiliary equipment (filter, deaerator), installation, etc.
- Environmental conditions: ambient temperature, humidity, electromagnetic interference, safety, explosion-proof, pipeline vibration, etc.
- Economic factors: instrument purchase cost, installation cost, operation cost, calibration cost, maintenance cost, instrument service life, spare parts, etc.