Abstract
If bubble nuclei are the cause of cavitation, how are they initially produced? According to what Washio et al. have found out so far, there are two possible ways for cavitation nuclei to be generated in liquid flows: separation of flow and a relative motion between solids contacting in liquid. The present article intends to reinforce that assertion by observing the cavitation occurring in an oil hydraulic poppet valve. At a certain flowrate, a microscopic cavity suddenly emerged on the valve seat where the flow separated. As the flowrate increased, the cavity developed extending circumferentially on the seat and discharged bubbles by splitting. A collision of the poppet with the valve seat also caused the generation of a cavity. As the poppet was away from the seat after the collision, the cavity shrunk leaving behind a bubble. Cavities generated on the seat by flow separation regularly repeated a process of growth and shrinkage accompanied by bubble discharge, which induced flow pulsation and consequently vibration of the poppet supported by a spring as well. Moreover, these cavities brought about so-called 'choking' in the poppet-seat constriction and acted to increase the pressure loss there by narrowing its cross-section.
| Original language | English |
|---|---|
| Pages (from-to) | 947-958 |
| Number of pages | 12 |
| Journal | Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science |
| Volume | 224 |
| Issue number | 4 |
| DOIs | |
| Publication status | Published - Jan 1 2010 |
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Keywords
- Bubble nuclei
- Cavitation inception
- Cavity generation
- Choking
- Flow separation
- Oil hydraulic
- Poppet valve
- Pressure loss
- Self-excited vibration
- Solid contact
ASJC Scopus subject areas
- Mechanical Engineering
Cite this
Nucleation and subsequent cavitation in a hydraulic oil poppet valve. / Washio, S.; Kikui, S.; Takahashi, Satoshi.
In: Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science, Vol. 224, No. 4, 01.01.2010, p. 947-958.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Nucleation and subsequent cavitation in a hydraulic oil poppet valve
AU - Washio, S.
AU - Kikui, S.
AU - Takahashi, Satoshi
PY - 2010/1/1
Y1 - 2010/1/1
N2 - If bubble nuclei are the cause of cavitation, how are they initially produced? According to what Washio et al. have found out so far, there are two possible ways for cavitation nuclei to be generated in liquid flows: separation of flow and a relative motion between solids contacting in liquid. The present article intends to reinforce that assertion by observing the cavitation occurring in an oil hydraulic poppet valve. At a certain flowrate, a microscopic cavity suddenly emerged on the valve seat where the flow separated. As the flowrate increased, the cavity developed extending circumferentially on the seat and discharged bubbles by splitting. A collision of the poppet with the valve seat also caused the generation of a cavity. As the poppet was away from the seat after the collision, the cavity shrunk leaving behind a bubble. Cavities generated on the seat by flow separation regularly repeated a process of growth and shrinkage accompanied by bubble discharge, which induced flow pulsation and consequently vibration of the poppet supported by a spring as well. Moreover, these cavities brought about so-called 'choking' in the poppet-seat constriction and acted to increase the pressure loss there by narrowing its cross-section.
AB - If bubble nuclei are the cause of cavitation, how are they initially produced? According to what Washio et al. have found out so far, there are two possible ways for cavitation nuclei to be generated in liquid flows: separation of flow and a relative motion between solids contacting in liquid. The present article intends to reinforce that assertion by observing the cavitation occurring in an oil hydraulic poppet valve. At a certain flowrate, a microscopic cavity suddenly emerged on the valve seat where the flow separated. As the flowrate increased, the cavity developed extending circumferentially on the seat and discharged bubbles by splitting. A collision of the poppet with the valve seat also caused the generation of a cavity. As the poppet was away from the seat after the collision, the cavity shrunk leaving behind a bubble. Cavities generated on the seat by flow separation regularly repeated a process of growth and shrinkage accompanied by bubble discharge, which induced flow pulsation and consequently vibration of the poppet supported by a spring as well. Moreover, these cavities brought about so-called 'choking' in the poppet-seat constriction and acted to increase the pressure loss there by narrowing its cross-section.
KW - Bubble nuclei
KW - Cavitation inception
KW - Cavity generation
KW - Choking
KW - Flow separation
KW - Oil hydraulic
KW - Poppet valve
KW - Pressure loss
KW - Self-excited vibration
KW - Solid contact
UR - http://www.scopus.com/inward/record.url?scp=77951692591&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=77951692591&partnerID=8YFLogxK
U2 - 10.1243/09544062JMES1618
DO - 10.1243/09544062JMES1618
M3 - Article
AN - SCOPUS:77951692591
VL - 224
SP - 947
EP - 958
JO - Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science
JF - Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science
SN - 0954-4062
IS - 4
ER -