Calculation method for cavitation coefficient of vertical shaft axial flow paddle turbine power station

Abstract

The invention relates to a water turbine in a hydropower station, and discloses a calculation method for the cavitation coefficient of a vertical-axis axial-flow paddle-type hydraulic turbine power station, which can more reasonably calculate the cavitation coefficient of a vertical-axis axial-flow paddle-type hydraulic turbine power station to meet new hydropower engineering requirements. The inventive method is as follows: determine the specific rotational speed of the axial flow propeller type water turbine, and described specific rotational speed is denoted as n s ; Determine the maximum application head of the axial flow paddle turbine, and the maximum application head is denoted as H max , and judge H max range; according to H max The formula for calculating the cavitation coefficient of the power station in the corresponding range calculates the cavitation coefficient of the power station, and the cavitation coefficient of the power station is denoted as σ p , the formula for calculating the cavitation coefficient of the power station in the range is: when H max ≤30m, when H max When the distance is greater than 30m, the present invention is applicable to the calculation of the cavitation coefficient of a vertical-axis axial-flow paddle turbine power station, and can better meet the requirements of new hydropower projects.

Description

technical field [0001] The invention relates to a hydroturbine in a hydropower station, in particular to a calculation method for the cavitation coefficient of a vertical-axis flow-to-paddle hydroturbine power station. Background technique [0002] In a hydropower station equipped with a vertical shaft axial flow paddle turbine, the installation elevation of the turbine is the elevation of the centerline of the guide vane of the turbine, and the suction height of the turbine is the elevation difference from the axis of the runner blade to the tail water level of the power station. Raising the suction height and installation elevation of the turbine can reduce the underwater engineering volume and investment of the main powerhouse; while reducing the suction height and installation elevation of the turbine can improve the cavitation performance of the turbine, which is conducive to the stable operation of the unit and prolongs the service life of the unit. Therefore, how to r...

AI Technical Summary

Problems solved by technology

Since this method estimates the cavitation coefficient σ of the power station according to the statistical formula p , there are many statistical formulas of this kind at present, because the water turbine parameter sample data on which each statistical formula is based is before the 1970s and 1980s or a certain water head section or a certain specific speed n s range, there are certain limitations, the results estimated by different statistical formulas for the same hydropower project are different, and some even have large differences, so it is impossible to correctly select

Therefore, both methods 1 and 2 cannot meet the requirements of hydropower engineering for the continuous development of new technologies, new materials, new processes, and new structures. The estimated cavitation coefficient σ p Generally, it is also difficult to meet the new hydropower engineering requirements

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