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Title: Transient cavitation in fluid-structure interactions

Abstract

A generalized column separation model is extended to predict transient cavitation associated with fluid-structure interactions. The essential feature of the combined fluid-structure interaction calculations is the coupling between the fluid transient, which is computed one dimensionally, and the structural response which can be multidimensional. Proper coupling is achieved by defining an average, one-dimensional, structural velocity and by assuming a spatially uniform pressure loading of the structure. This procedure is found to be effective even for complex finite element structural models for which the required computational time step is orders of magnitude smaller than that for the fluid transient. Computational examples and comparison with experimental data show that neglecting cavitation and setting the fluid velocity at all times equal to that of the structural boundary leads to unreal negative pressure predictions. A properly coupled column separation model reproduces the important features of fluid-structure interactions, converges rapidly, and gives reasonable fluid and structural response predictions. 9 refs.

Authors:
; ; ;
Publication Date:
Research Org.:
Argonne Natl Lab, Ill, USA
OSTI Identifier:
5481889
Resource Type:
Journal Article
Resource Relation:
Journal Name: J. Pressure Vessel Technol.; (United States); Journal Volume: 103:4
Country of Publication:
United States
Language:
English
Subject:
42 ENGINEERING; FLUID FLOW; CAVITATION; FLUID-STRUCTURE INTERACTIONS; TRANSIENTS; MECHANICAL STRUCTURES; EVALUATION; FINITE ELEMENT METHOD; PIPES; NUMERICAL SOLUTION; 420200* - Engineering- Facilities, Equipment, & Techniques; 420400 - Engineering- Heat Transfer & Fluid Flow

Citation Formats

Kot, C.A., Hsieh, B.J., Youngdahl, C.K., and Valentin, R.A. Transient cavitation in fluid-structure interactions. United States: N. p., 1981. Web. doi:10.1115/1.3263412.
Kot, C.A., Hsieh, B.J., Youngdahl, C.K., & Valentin, R.A. Transient cavitation in fluid-structure interactions. United States. doi:10.1115/1.3263412.
Kot, C.A., Hsieh, B.J., Youngdahl, C.K., and Valentin, R.A. Sun . "Transient cavitation in fluid-structure interactions". United States. doi:10.1115/1.3263412.
@article{osti_5481889,
title = {Transient cavitation in fluid-structure interactions},
author = {Kot, C.A. and Hsieh, B.J. and Youngdahl, C.K. and Valentin, R.A.},
abstractNote = {A generalized column separation model is extended to predict transient cavitation associated with fluid-structure interactions. The essential feature of the combined fluid-structure interaction calculations is the coupling between the fluid transient, which is computed one dimensionally, and the structural response which can be multidimensional. Proper coupling is achieved by defining an average, one-dimensional, structural velocity and by assuming a spatially uniform pressure loading of the structure. This procedure is found to be effective even for complex finite element structural models for which the required computational time step is orders of magnitude smaller than that for the fluid transient. Computational examples and comparison with experimental data show that neglecting cavitation and setting the fluid velocity at all times equal to that of the structural boundary leads to unreal negative pressure predictions. A properly coupled column separation model reproduces the important features of fluid-structure interactions, converges rapidly, and gives reasonable fluid and structural response predictions. 9 refs.},
doi = {10.1115/1.3263412},
journal = {J. Pressure Vessel Technol.; (United States)},
number = ,
volume = 103:4,
place = {United States},
year = {Sun Nov 01 00:00:00 EST 1981},
month = {Sun Nov 01 00:00:00 EST 1981}
}
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