Hydraulic Performance and Energy Dissipation Mechanism Analysis of the Tesla-Shaped Emitter

In this paper, a tesla-shaped emitter is proposed based on the structure of the tesla valve as the source of inspiration, so that the water flow in the channel would produce a variety of energy dissipation phenomena, such as diversion, hedging, and mixing, to explore the hydraulic performance and energy dissipation mechanism of the tesla-shaped emitter. The channel structure parameters were taken as factors, and 16 groups of orthogonal tests were arranged. Based on CFD technology, the pressure-flow relationship curve slope, flow ratio between the main channel and secondary channel, flow field, and head loss of the emitter were calculated and analyzed for different combinations of structural parameters. Based on a significance level & alpha; = 0.05 test, the main channel inlet section length (L-3) had a significant impact on the curve slope, and the secondary channel length (L-1) and main channel inlet section length (L-3) had a significant impact on the flow. The multiple linear regression mathematical models between the channel structure parameters and the curve slope and the flow were constructed. The larger the ratio between the main channel and the secondary channel flow, the better the hydraulic performance of the emitter. The channel unit loss coefficient increased linearly with the increase of the emitter inlet pressure, and its value ranged from 4.5769 to 8.1716, with an excellent energy dissipation effect. The hedge mixing of the water flow was the core of the energy dissipation of the tesla-shaped emitter. By appropriately increasing the inlet size of the main channel and other elements to increase the main channel flow and optimize the flow ratio between the main channel and the secondary channel, the mixing was improved, which consequently improved the hydraulic performance of the emitter.

Automated summary

In this study, a tesla-shaped emitter based on the structure of the tesla valve was proposed to explore its hydraulic performance and energy dissipation mechanism. Computational fluid dynamics (CFD) technology was used to analyze the pressure-flow relationship, flow field, and head loss under different structural parameters. The main channel inlet section length and the secondary channel length were found to have significant impacts on the curve slope and flow. Regression models were established to predict the curve slope and flow based on the channel structure parameters. It was found that a larger flow ratio between the main channel and the secondary channel resulted in better hydraulic performance, and the unit loss coefficient showed excellent energy dissipation. The hedge mixing of the water flow was identified as the core of energy dissipation for the tesla-shaped emitter.