domesticvortex flow meterThe experimental research on dry calibration began in the late 1980s. At that time, some domestic flow experts analyzed the characteristics of vortex flowmeters and the research and production status of instruments in China. At the "Seventh Five Year Plan" development conference for flow meters, they proposed the possibility of dry calibration of vortex flowmeters and suggested conducting research on dry calibration. These two proposals have received national support, and the research on dry calibration of vortex flowmeters has been included as a technical foundation research project in the "Seventh Five Year Plan" National Science and Technology Research Program, led by Chongqing Industrial Automation Instrument Research Institute.

In 1987, China began to formulate industry standards and national metrological verification regulations for "vortex flow sensors". Combining the standards and regulations, two experimental verifications were conducted on the basic errors and installation effects of vortex flow sensors. The experimental results of these two works provide a basis for the formulation of standards and regulations.

The research and experimental work on dry calibration of vortex flowmeter includes the following contents:

1) Selection test of different shaped generators;

2) Experimental study on the influence of geometric parameters on flow characteristics;

3) The machining tolerance of the body and the assembly impact test;

4) Establishment and prediction of mathematical model for Strouhal number SR (instrument coefficient K);

5) Applying the principle of similarity to predict and verify the SR values of vortex street flowmeters with different diameters.

By the end of 1990, this work had basically completed the above five aspects and achieved preliminary results. However, there is still a lot of work to be done to achieve true dry calibration. Due to various reasons, this work has not been further carried out, and it is believed that someone will continue to carry out this work at some point in the future. Based on the suggestions of experts, we will introduce the previous work and provide its experimental methods for future reference in this field.