Cavitation model correction method suitable for moving boundary cavitation streaming

Abstract

The invention relates to a cavitation model correction method suitable for moving boundary cavitation streaming, and belongs to the technical field of hydraulic machinery. The cavitation model correction method includes the steps: defining a filtering scale through a vortex structure judgment criterion, and dividing the flow field into a vortex region and a non-vortex region based on the filteringscale; multiplying the evaporation phase coefficient Cd of the cavitation model in the vortex area by the evaporation phase dynamic correction coefficient fd, multiplying the condensation phase coefficient Cp by the condensation phase dynamic correction coefficient fp, and keeping the evaporation phase coefficient Cd and the condensation phase coefficient Cp of the cavitation model in the non-vortex area at the original model values; and substituting the evaporation phase coefficient Cd and the condensation phase coefficient Cp into the cavitation model mass transfer equation again to solve the cavitation flow field. According to the cavitation model correction method, a vortex structure is adopted as a filtering scale, and numerical prediction simulation is associated with cavitation flow field information, and the influence of a dynamic boundary on vapor-liquid two-phase mass transmission in a cavitation model is considered, and the dynamic boundary cavitation streaming prediction precision is greatly improved.

Description

technical field [0001] The invention relates to a cavitation model correction method applicable to cavitation flow around dynamic boundaries, and belongs to the technical field of hydraulic machinery. Background technique [0002] In the study of hydraulic machinery, the additional force generated by the rotation and the disturbance of the static and dynamic components have an important impact on the turbulent flow process, the development of the boundary layer, and the temporal and spatial distribution of the flow structure. It is the focus and difficulty of the research. In the transient process of propeller, turbo pump, hydraulic turbine start-up and shutdown, runaway, load increase and decrease, etc., the transient flow in the transient process will change the effective angle of attack of the lifting surface, and its internal flow is complex and changeable, showing a strong Instability, especially under cavitation conditions, seriously affects the working performance of...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to solve the problem of large experimental research costs and less refined flow field information in hydraulic mechanical cavitation phenomena, and to provide a cavitation model correction method suitable for cavitation flow around dynamic boundaries , this method can improve the numerical prediction accuracy of the cavitation flow around the moving boundary

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