Observations of Shock Waves in Cloud Cavitation
CaltechAUTHORS
View Archive Info| Field | Value | |
| Title |
Observations of Shock Waves in Cloud Cavitation
|
|
| Creator |
Reisman, G. E.
Wang, Y.-C. Brennen, C. E. |
|
| Subject |
Caltech Library Services
|
|
| Description |
This paper describes an investigation of the dynamics and acoustics of cloud cavitation, the structures which are often formed by the periodic breakup and collapse of a sheet or vortex cavity. This form of cavitation frequently causes severe noise and damage, though the precise mechanism responsible for the enhancement of these adverse effects is not fully understood. In this paper, we investigate the large impulsive surface pressures generated by this type of cavitation and correlate these with the images from high-speed motion pictures. This reveals that several types of propagating structures (shock waves) are formed in a collapsing cloud and dictate the dynamics and acoustics of collapse. One type of shock wave structure is associated with the coherent collapse of a well-defined and separate cloud when it is convected into a region of higher pressure. This type of global structure causes the largest impulsive pressures and radiated noise. But two other types of structure, termed 'crescent-shaped regions' and 'leading-edge structures' occur during the less-coherent collapse of clouds. These local events are smaller and therefore produce less radiated noise but the interior pressure pulse magnitudes are almost as large as those produced by the global events. The ubiquity and severity of these propagating shock wave structures provides a new perspective on the mechanisms reponsible for noise and damage in cavitating flows involving clouds of bubbles. It would appear that shock wave dynamics rather than the collapse dynamics of single bubbles determine the damage and noise in many cavitating flows. |
|
| Date |
1998-01
|
|
| Type |
Article
PeerReviewed |
|
| Format |
application/pdf
|
|
| Identifier |
http://authors.library.caltech.edu/145/1/REI179.pdf
Reisman, G. E. and Wang, Y.-C. and Brennen, C. E. (1998) Observations of Shock Waves in Cloud Cavitation. Journal of Fluid Mechanics, 355 . pp. 255-283. ISSN 0022-1120. http://resolver.caltech.edu/CaltechAUTHORS:REIjfm98 <http://resolver.caltech.edu/CaltechAUTHORS:REIjfm98> |
|
| Relation |
http://resolver.caltech.edu/CaltechAUTHORS:REIjfm98
http://authors.library.caltech.edu/145/ |
|