Turbine capable of achieving direct backing and with primary-secondary moving blade structure

Abstract

The invention aims to provide a turbine capable of achieving direct backing and with a primary-secondary moving blade structure. The turbine comprises a hub, a backing turbine primary blade and a backing turbine secondary blade, the backing turbine primary blade and the backing turbine secondary blade are uniformly mounted between a casing and the hub in a staggered manner in the circumferential direction, the hub is an ahead turbine last-stage moving blade tip connecting ring, and the trailing edge point of the backing turbine secondary blade and the trailing edge point of the backing turbine primary blade are located at the same axial position; and the distance b2 between the leading edge point and the leading edge frontal line of the backing turbine primary blade is changed by the backing turbine secondary blade according to the flowing working condition, and b2 does not exceed 65% of the axial chord length b1 of the backing turbine primary blade. The primary blade and the secondary blade are arranged in an axial flow turbine moving blade cascade in a staggered manner, the binding capacity of the backing turbine blade cascade on airflow is improved, large-scale separation is reduced, the turbine power and efficiency are improved, and good working reliability is achieved.

Description

technical field [0001] The invention relates to a gas turbine, in particular to a turbine of a marine gas turbine. Background technique [0002] In the field of ship power, the gas turbine is an ideal power equipment, but it cannot be reversed directly to realize the reverse of the ship. In order to make up for this disadvantage, people try to add a reverse turbine to the outside of the final stage of the conventional power turbine to realize the reversal of the power turbine in the gas turbine, that is, the integrated direct reverse turbine is composed of two parts: the forward turbine and the reverse turbine. The reverse turbine has only one stage and is located above the last-stage blade cascade of the forward turbine; the moving blades of the reverse turbine and the last-stage movable blades of the forward turbine are connected through an intermediate ring to form double-layer blades. On the contrary, the purpose of forward and reverse rotation of the turbine is realize...

AI Technical Summary

Problems solved by technology

Due to the large size of the marine gas turbine, especially in the final stage of the power turbine, the radius of the outlet casing is close to 1m, and the radius of the hub of the reverse turbine attached to the upper part of the forward turbine is too large, resulting in extremely low consistency of the moving blades of the reverse turbine, which makes the reverse turbine The capacity of the moving blade cascade to bind the airflow is relatively low, and a large-scale airflow separation occurs at the maximum curvature of the suction surface of the moving blade, resulting in low efficiency of the reversing turbine

Since the double-layer blade needs to consider the strength of the lower blade, the upper reverse turbine blade cascade is limited by weight and cannot have normal consistency

Therefore, it is hoped that there will be a reverse turbine that can effectively reduce the flow separation at the back of the blade without greatly improving the quality of the moving blades of the reverse turbine and without damaging the strength of the moving blades of the front turbine. Efficient reverse turbines are even less researched and explored

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