This article investigates the effect of inlet shape, entrance length, and turbulence promoters on mass transfer by using 3D-printed electrolyzers. Our results show that the inlet design can promote turbulence and lead to an earlier transition to turbulent flow. The Reynolds number at which the transition occurs can be predicted by the ratio of the cross-sectional area of the inlet to the cross-sectional area of the electrolyzer channel. A longer entrance length results in more laminar behavior and a later transition to turbulent flow. With an entrance length of 550 mm, the inlet design did no longer affect the mass transfer performance significantly. The addition of gyroid type turbulence promoters resulted in a factor of 2 to 4 increase in mass transfer depending on inlet design, entrance length, and the type of promoter. From one configuration to another, there was a minimal variation in pressure drop (<1600 Pa).

中文翻译：

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3D打印电解器中的传质：入口效应的重要性

本文研究了入口形状，入口长度和湍流促进剂对3D打印电解池传质的影响。我们的结果表明，进气口设计可以促进湍流并导致更早地过渡到湍流。可以通过入口的横截面积与电解槽的横截面积之比来预测发生转变的雷诺数。较长的入口长度会导致更多的层流行为，并导致稍后过渡到湍流。入口长度为550 mm，进样口设计不再显着影响传质性能。螺旋型湍流促进剂的加入导致传质增加2到4倍，具体取决于入口设计，入口长度和促进剂的类型。