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The theoretical basis for flow measurement using vortex flow meters is the well-known \"Kármán vortex street\" principle in fluid mechanics; a non-streamlined cylindrical body with an axis perpendicular to the flow direction is placed within the flowing fluid, and this is known as a vortex generator. When a fluid flows around a vortex generator, two rows of asymmetric yet regularly alternating vortices are generated downstream of the vortex generator; this is what is known as the Karman vortex street. Regarding the installation of vortex flowmeters, the following aspects should be taken into consideration. Flow meter: yunrun.com.cn/product/list_86.html 1. Choose the installation location and environment for vortex flow meters carefully. Stay away from high-power equipment, high-frequency equipment, and high-voltage switching equipment ； Avoid areas affected by high temperatures and radiation sources, as well as locations with severe vibrations and highly corrosive environments; at the same time, consider the convenience of installation and maintenance. 2. There must be sufficient straight pipe sections upstream and downstream of the vortex flow meter. If there are two 90 degrees on the same plane upstream of the sensor installation point. For elbows: the upstream straight pipe section should be ≥ 25D, and the downstream straight pipe section should be ≥ 5D. If there are two 90 degrees on different planes upstream of the sensor installation point. For elbows: the upstream straight pipe section should be ≥ 40D, and the downstream straight pipe section should be ≥ 5D. The control valve should be installed at a distance of 5D downstream of the sensor; if it must be installed upstream of the sensor, the straight pipe section upstream of the sensor should be at least 50D long, and the section downstream should be at least 5D long. 3. Installing a vortex flow meter in a horizontal pipe is the most common installation method for flow sensors. When measuring gas flow, if the gas under measurement contains a small amount of liquid, the sensor should be installed at a higher position in the pipeline. When measuring liquid flow, if the liquid being measured contains a small amount of gas, the sensor should be installed at a lower position in the pipeline. 4. Installation of vortex flowmeter sensors in vertical pipes. When measuring gas flow, the sensor can be installed on a vertical pipe, with no restriction on the flow direction. If the gas to be measured contains a small amount of liquid, the gas flow should be from bottom to top. When measuring liquid flow, the flow direction of the liquid should be from bottom to top: this prevents the weight of the liquid from being added additionally to the probe. 5. Vibration reduction measures shall be taken for the pipeline of the vortex flow meter. Sensors should be installed as far as possible away from pipes with high vibration levels, especially lateral vibration. If installation is unavoidable, vibration reduction measures must be taken: pipe fastening devices should be installed at 2D positions upstream and downstream of the sensor, along with vibration damping pads. 6. Inverted installation of the vortex flowmeter sensor in a horizontal pipeline. This installation method is generally not recommended. This installation method is not suitable for measuring ordinary gases or superheated steam. It can be used to measure saturated steam, and is suitable for measuring high-temperature liquids or in situations where the pipes need to be cleaned frequently. 7. Installation of vortex flowmeter sensors on insulated pipes. When measuring high-temperature steam, the insulation layer shall not exceed one-third of the height of the support. 8. Selection of pressure and temperature measurement points for vortex flowmeters. Depending on the measurement requirements, when it is necessary to measure pressure and temperature near the sensor, the pressure measurement point should be located 3–5D downstream of the sensor, while the temperature measurement point should be located 6–8D downstream of the sensor. 9. The vortex flowmeter sensor is installed on the side of a horizontal pipeline. Regardless of the fluid being measured, the sensor can be installed on the upper side of horizontal pipes, especially when measuring superheated steam, saturated steam, and low-temperature liquids. If conditions permit, side installation is preferred, as this reduces the impact of the fluid temperature on the amplifier. Vortex flowmeters are suitable for measuring liquids, gases, steam, low-temperature media, as well as various corrosive and radioactive media. They are instruments with high measurement accuracy and are currently widely used.