Propeller cavitation wake flow fine feature multivariate statistical modeling method

Abstract

The invention discloses a propeller cavitation wake flow fine feature multivariate statistical modeling method, and relates to the technical field of underwater acoustic target recognition. The methodcomprises: 1, setting propeller cavitation wake flow whole watershed unsteady numerical calculation parameters, and obtaining a pressure pulsation numerical calculation signal x (i); 2, obtaining atlas information of pressure pulsation signal processing; 3, extracting pressure pulsation signal characteristics, and carrying out correlation analysis; and 4, according to a correlation analysis result, carrying out characteristic relationship modeling from the propeller cavitation wake flow target characteristic parameters to the cavitation flow field characteristic parameters; and 5, utilizing the acquired cavitation wake flow pressure pulsation signal characteristics of the propeller to judge the side inclination angle characteristics of the propeller. The mapping relation between the cavitation flow field characteristic parameter space and the propeller and flow field parameter space is defined, a fine characteristic model of the cavitation flow field characteristic parameter space andthe propeller and flow field parameter space is established, and compared with the prior art, the method is a new thought and has important directivity value for the underwater target classificationand recognition technology.

Description

technical field [0001] The invention relates to a multivariate statistical modeling method for fine features of propeller cavitation wake, and has important application prospects in the technical field of underwater acoustic target recognition. Background technique [0002] The speed of the rotating ship propeller often reaches tens of meters per second at the tip of the blade. This high-speed rotation causes an obvious local pressure drop in the seawater around the blade, so that strong cavitation often occurs at the tip of the blade and even on the blade surface near the hub. In addition, the propeller works in the wake field of the ship, and the line shape and appendage of the hull are not centrally symmetrical, so the wake field of the ship has obvious circumferential inhomogeneity. In this way, the relative velocity and pressure of the periodically rotating blade and the non-uniform wake in contact with it have periodic changes, so that the intensity of cavitation also...

AI Technical Summary

Problems solved by technology

[0005] In recent decades, a lot of research has been done on the radiation noise generated by cavitation, but there are not many reports on the mechanism of the ship propeller cavitation noise that has attracted much attention in the field of hydroacoustics.

On the other hand, propeller cavitation has become a research hotspot in the field of fluid mechanics, and there are many related works, but there is not much about the radiation noise caused by cavitation

Although some scholars have used statistical theory to study propeller cavitation noise, they have not combined the specific characteristics of propellers.

And because the formation mechanism of cavitation has not been fully revealed at present, it is very difficult and challenging to analyze the characteristics of propeller cavitation noise calculation based on spherical cavitation theory

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