Impedance pump is a simple valveless pumping mechanism, which transports fluid through the mismatch of impedance in the system. Mismatch in impedance occurs when an asymmetrical periodic excitation is exerted on the elastic tube. Periodic asymmetrical excitation will then produce a unidirectional flow. Considering a multi-stage system with a single and constant power source, it is well expected that there would be pumping limitation to which the enhancement can reach. A multi-stage open-loop impedance pump is developed in the current work. The current work experimentally analyzes and evaluates the pumping performance of a multi-stage open-loop impedance pump, with emphasis on the flow rates induced and pumping limitation. Analyses of flow rates, pressure head and excitation frequencies are performed in its non-dimensional form. Taking a single-stage system as benchmark, enhancement of 35 and 33.3% is shown in the flow rate and pressure head respectively for a two-stage system. Enhancement of 110 and 60% is shown in flow rate and pressure head of a three-stage system in comparison to the single-stage system. For four-stage system, however, only 27 and 46.7% increments are demonstrated in the flow rate and pressure head, respectively. The implementation of multi-stage system with single constant power input is demonstrated to be limited only to the three-stage system where the declined pumping performance is exhibited in a four-stage system.

中文翻译：

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多级开环阻抗泵的性能评估

阻抗泵是一种简单的无阀泵送机构，它通过系统中阻抗的不匹配来输送流体。当在弹性管上施加不对称的周期性激励时，会发生阻抗不匹配的情况。周期性的不对称激励将产生单向流。考虑到具有单个且恒定功率源的多级系统，可以预料的是，增强将达到的泵送限制。目前的工作是开发一种多级开环阻抗泵。当前的工作是通过实验分析和评估多级开环阻抗泵的泵送性能，重点是感应的流量和泵送限制。流量，压头和激励频率的分析以其无量纲形式进行。以单级系统为基准，两级系统的流量和压头分别提高了35％和33.3％。与单级系统相比，三级系统的流速和压头提高了110％和60％。但是，对于四级系统，流量和压头分别仅增加了27％和46.7％。证明了具有单个恒定功率输入的多级系统的实施仅限于三级系统，在该三级系统中，四级系统的泵送性能下降。与单级系统相比，三级系统的流速和压头提高了110％和60％。但是，对于四级系统，流量和压头分别仅增加了27和46.7％。证明了具有单个恒定功率输入的多级系统的实施仅限于三级系统，在四级系统中泵送性能下降。与单级系统相比，三级系统的流速和压头提高了110％和60％。但是，对于四级系统，流量和压头分别仅增加了27％和46.7％。证明了具有单个恒定功率输入的多级系统的实施仅限于三级系统，在该三级系统中，四级系统的泵送性能下降。