The vortex flowmeter
is based on the Karman vortex principle. It is mainly manifested as a non-streamline vortex generator (bluff body) is set in the flowing fluid, and two rows of regular vortices are alternately generated from both sides of the vortex generator. It is widely used in petroleum, chemical, metallurgical, thermal, textile, paper and other industries for superheated steam, saturated steam, compressed air and general gases (oxygen, nitrogen, hydrogen, natural gas, coal gas, etc.), water and liquids (such as water, gasoline, etc.) , Alcohol, benzene, etc.) measurement and control.
Generally, the flow rate of biogas pipeline is small, and it is generally measured by reducing diameter. We can choose two types of structure, flange card type and flange type. When selecting the type, we must choose to understand the small flow rate, common flow rate and large flow rate of biogas. Most biogas measurement sites do not have a power source, so we can choose battery-powered vortex flowmeters. If the user needs to introduce the display of the meter indoors, an integrated vortex flowmeter can be used, and the output signal is led to the flow totalizer installed in the room through a cable. The vortex flowmeter can display the instantaneous flow and cumulative flow of biogas .
When installing a vortex flowmeter to measure biogas, if a valve is installed near the upstream of the installation point, and the valve is constantly opened and closed, it will have a great impact on the service life of the sensor. It is very easy to cause permanent damage to the sensor. Avoid installing on very long overhead pipelines. After a long period of time, the sagging of the sensor will easily cause the sealing leakage between the sensor and the flange. If you have to install it, you must install the pipeline at the upstream and downstream 2D of the sensor. Fastening device.
To ensure complete functionality, the flow pattern at the entrance should not be disturbed. The length of the upstream straight pipe section should be approximately 15 times the flowmeter diameter (D), and the length of the downstream straight pipe section should be approximately 5 times the flowmeter diameter (D). When a non-streamline vortex sounder is set in the fluid, two rows of regular vortices are alternately generated from both sides of the vortex. This vortex is called the Karman vortex street. In a certain flow range, the vortex separation frequency is proportional to the average flow velocity in the pipeline. The capacitance probe or piezoelectric probe (detector) is installed in the vortex generator and the corresponding circuit is configured to form a capacitance detection vortex flowmeter
or Piezoelectric detection type vortex flow sensor.