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Working principle of the intelligent helical vortex flowmeter: The helical vortex flowmeter operates on the principle of vortex precession. When fluid flows into a vortex flow meter, it is first forced to rotate after passing through a set of fixed spiral vanes, thereby forming a vortex flow. The center of the vortex is the \"vortex core\", a region where the fluid’s rotational speed is very high; surrounding this core is a circumferential flow. As the fluid passes through the constricting section, the vortex accelerates, and the diameter of the vortex core gradually decreases while its intensity increases. At this point, the vortex core is aligned with the axis of the flow meter. When entering the expanding section, the vortex slows down sharply, pressure rises, and the pressure in the central area is lower than that around it, resulting in local backflow. Due to this backflow, the vortex core deviates from the central axis and moves in a helical motion along the walls of the expanding section, always around the central axis. The frequency of this helical motion is proportional to the flow velocity of the fluid. Therefore, by measuring the frequency of the vortex flow, it is possible to determine both the flow velocity and the volumetric flow rate. Structural optimization scheme for the vortex swirl meter: To address issues such as high pressure loss and weak signal strength at low flow rates in existing vortex swirl meters, a plan for structural improvements and parameter optimization was proposed. The meter under improvement is a DN50 gas vortex swirl meter; its internal structure is shown in Figure 2. The length of the meter is 232 mm, the diameter of the inlet pipe is 50 mm, the length of the contraction section is 94.2 mm, the diameter of the expansion section is 36 mm with a length of 35.8 mm, and the length of the expansion portion is 12 mm, with an expansion angle of 60°. The specific improvements and parameter optimization studies are as follows: 1. The number of vanes on the swirl generator is increased. The original number of vanes was 6; one more vane is added, and to ensure that the flow area does not decrease, the thickness of the vanes is reduced from 2.5 mm to 1.5 mm. The helix angle remains unchanged at 30°. 2. Add guide vane sections at the inlet of the swirl generator. The original swirl generator blades did not have a flow-guiding section in the inlet section; the angle between the blades and the incoming flow was 60°, and the flow did not enter tangentially, which led to severe flow separation. Flow separation results in increased flow disturbances and flow resistance. Therefore, the improvement proposal considers lengthening and bending the original swirl generator blades so that the angle between the inlet and the incoming flow is 0°, meaning the flow enters tangentially, in order to improve the flow condition. 3. Regarding the parameters of the flow meter housing, the expansion angle and contraction ratio were studied. As mentioned earlier, as the vortex enters the expansion section, it slows down rapidly, resulting in local backflow. The vortex core deviates from the central axis and strikes the wall surface, causing pressure fluctuations. Therefore, the size of the expansion angle has a significant impact on the motion of the vortex core. This paper will conduct simulation calculations for the three cases of 30°, 60°, and 90°. The contraction ratio is also a relatively important parameter; the larger the contraction ratio, the greater the increase in the vortex rotation speed. However, this simultaneously leads to an increase in pressure loss, and it may reduce the impact of disturbances in the vortex core in the expansion section on the impact wall. This paper examines the two shrinkage ratios of 50∶36 and 50∶32. It should be noted that when studying the expansion angle and contraction ratio parameters, the swirl generator model considered was one equipped with guide vanes. For more information, please visit the company’s official website at http://www.yb1518.com/. Please retain this link when reproducing the content! http://www.yb1518.com/UploadFiles/20101022185438865.jpg