{"title":"开式水槽配置中的无阀泵送与非稳定性狭窄","authors":"C. Manopoulos, D. Mathioulakis","doi":"10.3390/fluids9060141","DOIUrl":null,"url":null,"abstract":"This work examines the beneficial role of an unsteady stenosis, not driven by any external energy source, as a means for augmenting the flow rate of a valveless pump in a hydraulic loop, including an open tank. In contrast to our previous work, in which the concept of the latter stenosis was introduced for the first time in a horizontal closed loop, here, gravity was taken into account. The stenosis neck cross-sectional area was controlled by the fluid pressure and the opposing force applied externally by a spring of adjustable tension. A pincher compressed and decompressed a part of the pump’s flexible tube periodically, with frequencies from 5 Hz to 11 Hz and compression ratios Ab from 24% to 65%. The presence of the stenosis increased the net flow rate by 19 times for Ab = 24% and 6.3 times for Ab = 38%; whereas for Ab = 65%, the flow rates were comparable. The volumetric efficiency varied from 30% to 40% under the presence of the stenosis, and from 2% to 20% without the stenosis. The role of the stenosis was to cause a unidirectional flow, opening during tube compression and closing during decompression. The pressure amplitudes along the flexible tube increased towards the rigid–flexible tube junction (as a result of the wave reflections), which were found to be significantly attenuated by the presence of the stenosis, whereas the flow rate pulsations did not exceed 10% of the mean at the peak net flow rates.","PeriodicalId":12397,"journal":{"name":"Fluids","volume":null,"pages":null},"PeriodicalIF":1.8000,"publicationDate":"2024-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Valveless Pumping with an Unsteady Stenosis in an Open Tank Configuration\",\"authors\":\"C. Manopoulos, D. Mathioulakis\",\"doi\":\"10.3390/fluids9060141\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"This work examines the beneficial role of an unsteady stenosis, not driven by any external energy source, as a means for augmenting the flow rate of a valveless pump in a hydraulic loop, including an open tank. In contrast to our previous work, in which the concept of the latter stenosis was introduced for the first time in a horizontal closed loop, here, gravity was taken into account. The stenosis neck cross-sectional area was controlled by the fluid pressure and the opposing force applied externally by a spring of adjustable tension. A pincher compressed and decompressed a part of the pump’s flexible tube periodically, with frequencies from 5 Hz to 11 Hz and compression ratios Ab from 24% to 65%. The presence of the stenosis increased the net flow rate by 19 times for Ab = 24% and 6.3 times for Ab = 38%; whereas for Ab = 65%, the flow rates were comparable. The volumetric efficiency varied from 30% to 40% under the presence of the stenosis, and from 2% to 20% without the stenosis. The role of the stenosis was to cause a unidirectional flow, opening during tube compression and closing during decompression. The pressure amplitudes along the flexible tube increased towards the rigid–flexible tube junction (as a result of the wave reflections), which were found to be significantly attenuated by the presence of the stenosis, whereas the flow rate pulsations did not exceed 10% of the mean at the peak net flow rates.\",\"PeriodicalId\":12397,\"journal\":{\"name\":\"Fluids\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":1.8000,\"publicationDate\":\"2024-06-12\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Fluids\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/10.3390/fluids9060141\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q3\",\"JCRName\":\"MECHANICS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Fluids","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.3390/fluids9060141","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"MECHANICS","Score":null,"Total":0}
Valveless Pumping with an Unsteady Stenosis in an Open Tank Configuration
This work examines the beneficial role of an unsteady stenosis, not driven by any external energy source, as a means for augmenting the flow rate of a valveless pump in a hydraulic loop, including an open tank. In contrast to our previous work, in which the concept of the latter stenosis was introduced for the first time in a horizontal closed loop, here, gravity was taken into account. The stenosis neck cross-sectional area was controlled by the fluid pressure and the opposing force applied externally by a spring of adjustable tension. A pincher compressed and decompressed a part of the pump’s flexible tube periodically, with frequencies from 5 Hz to 11 Hz and compression ratios Ab from 24% to 65%. The presence of the stenosis increased the net flow rate by 19 times for Ab = 24% and 6.3 times for Ab = 38%; whereas for Ab = 65%, the flow rates were comparable. The volumetric efficiency varied from 30% to 40% under the presence of the stenosis, and from 2% to 20% without the stenosis. The role of the stenosis was to cause a unidirectional flow, opening during tube compression and closing during decompression. The pressure amplitudes along the flexible tube increased towards the rigid–flexible tube junction (as a result of the wave reflections), which were found to be significantly attenuated by the presence of the stenosis, whereas the flow rate pulsations did not exceed 10% of the mean at the peak net flow rates.