阅读说明：本技术 用于预旋供气系统的带有径向跑道斜孔式接受孔的盖板盘 (Cover plate disc with radial runway inclined hole type receiving hole for pre-rotation gas supply system ) 是由 刘高文 王欣欣 冯青 余祥仙 于 2019-09-19 设计创作，主要内容包括：本发明涉及一种用于预旋供气系统的带有径向跑道斜孔式接受孔的盖板盘,包括沿周向均匀分布的多个接受孔；其特征在于：所述接受孔采用径向跑道斜孔式接受孔,轴向截面由两个平行的直道和两个半径相等的弯道组成,且孔沿盖板盘转动方向设有偏转角度α；所述接受孔的邻边为直道,上下为弯道；所述偏转角度α为接受孔进口截面与接受孔的流通面截面法线的夹角。由于本发明的接受孔与传统轴向跑道斜孔的盖板盘相比,在保证流通面积一定的情况下,带有径向跑道斜孔式接受孔的盖板盘的开孔率降低了42.5％,有效地提高了盖板盘的强度,安全性得到了保障。(The invention relates to a cover plate disc with radial runway inclined hole type receiving holes for a pre-rotation gas supply system, which comprises a plurality of receiving holes uniformly distributed along the circumferential direction; the method is characterized in that: the receiving holes are radial runway inclined hole type receiving holes, the axial section of each receiving hole is composed of two parallel straight paths and two bent paths with equal radius, and the receiving holes are provided with deflection angles alpha along the rotating direction of the cover plate disc; the adjacent sides of the receiving holes are straight paths, and the upper part and the lower part of the receiving holes are bent paths; the deflection angle alpha is the included angle between the inlet section of the receiving hole and the normal line of the section of the flow surface of the receiving hole. Compared with the traditional cover plate disc with the axial runway inclined holes, the receiving holes have the advantages that the opening rate of the cover plate disc with the radial runway inclined hole receiving holes is reduced by 42.5 percent under the condition of ensuring a certain flow area, the strength of the cover plate disc is effectively improved, and the safety is ensured.)

1. A cover plate disc with radial runway inclined hole type receiving holes for a pre-rotation gas supply system comprises a plurality of receiving holes which are uniformly distributed along the circumferential direction; the method is characterized in that: the receiving holes adopt radial runway inclined hole type receiving holes 16, the axial section consists of two parallel straight paths and two bent paths with equal radius, and the holes are provided with deflection angles alpha along the rotating direction of the cover plate disc; the adjacent sides of the receiving holes are straight paths, and the upper part and the lower part of the receiving holes are bent paths; the deflection angle alpha is the angle between the inlet cross-section 13 of the receiving opening and the normal of the cross-section of the flow surface 15 of the receiving opening.

2. The cover plate disk with radial racetrack ramp-hole receiving holes for pre-swirl air supply systems of claim 1, wherein: the deflection angle alpha is 30 deg..

Technical Field

The invention belongs to the field of application of a pre-rotation air supply system of an aeroengine, and relates to a cover plate disc with a radial runway inclined hole type receiving hole for the pre-rotation air supply system.

Background

With the increase of the working temperature of the turbine blade, the function of the prerotation system as an air supply system of an aircraft engine is particularly important. The cooling principle of the prerotation system is mainly that cooling air before entering the turbine blades generates a circumferential speed along the rotation direction of the disk, and the relative speed of cooling air flow and the turbine rotating disk is reduced, so that the relative total temperature of the air flow is reduced, the quality of the cooling air is improved, and the using amount of the cooling air is reduced. A prerotation system with excellent performance can obviously improve the safety and the service life of an aeroengine.

A prerotation system has both stationary and rotating components. At high rotational speeds, the strength of the rotating parts becomes important. The opening condition of the cover plate is an important factor influencing the strength of the cover plate. In addition, a key parameter for evaluating the pneumatic performance of the prerotation system is the temperature drop of the system, and the total temperature drop of the prerotation system mainly comes from the temperature drop of the prerotation nozzle and the temperature rise of the rotor component. If the inlet and outlet conditions of the system and the type of the prerotation nozzle are determined, in order to improve the performance of the prerotation system, the flow loss of the rotor component needs to be reduced, namely, the pressurization effect of the rotor component is improved.

The receiving aperture, which rotates downstream of the pre-swirl nozzle, is an important element that affects the pressurization of the rotor assembly and the strength of the cover plate disk. The main function of the cyclone is to introduce the preswirled high-speed gas flow into the cover plate cavity rotating at high speed. The types of receiving holes currently available include axial straight-through holes, axial raceway slant holes, and lobed receiving holes. The axial through hole and the axial runner hole have a larger included angle with the airflow at the inlet, so that the flow loss in the hole is increased, and the flow coefficient is lower. Although the axial runway inclined hole and the blade type receiving hole enable airflow to have a proper air inlet angle and improve the flow coefficient of the hole, the axial runway inclined hole can cause over-high opening rate and reduce the strength of the cover plate disc, and the blade type receiving hole has higher requirements on processing technology.

Disclosure of Invention

Technical problem to be solved

In order to avoid the defects of the prior art, the invention provides a cover plate disc with a radial runway inclined hole type receiving hole for a pre-rotation gas supply system, which overcomes the difficulties of low flow coefficient and high hole opening rate of the cover plate disc.

Technical scheme

a cover plate disc with radial runway inclined hole type receiving holes for a pre-rotation gas supply system comprises a plurality of receiving holes which are uniformly distributed along the circumferential direction; the method is characterized in that: the receiving holes adopt radial runway inclined hole type receiving holes 16, the axial section consists of two parallel straight paths and two bent paths with equal radius, and the holes are provided with deflection angles alpha along the rotating direction of the cover plate disc; the adjacent sides of the receiving holes are straight paths, and the upper part and the lower part of the receiving holes are bent paths; the deflection angle alpha is the angle between the inlet cross-section 13 of the receiving opening and the normal of the cross-section of the flow surface 15 of the receiving opening.

The deflection angle alpha is 30 deg..

Advantageous effects

Compared with the traditional cover plate disc with the axial runway inclined holes, the cover plate disc with the radial runway inclined hole type receiving holes for the pre-rotation gas supply system has the advantages that the opening rate of the cover plate disc with the radial runway inclined hole type receiving holes is reduced by 42.5 percent under the condition that the flow area is ensured to be constant, the strength of the cover plate disc is effectively improved, and the safety is guaranteed.

In addition, for the traditional cover plate disc, the receiving holes are mostly axial straight-through holes and axial runner holes, a large included angle exists between the airflow direction at the hole inlet and the hole axis direction, obvious vortex is generated near the leeward side of the hole, backflow is formed at the hole outlet, the flowing loss in the hole is increased, and the flow coefficient of the hole is reduced. And the swirl area increases with increasing air flow swirl ratio at the nozzle outlet, and the flow losses in the holes increase. Although the existing cover plate disc with the leaf-type receiving hole improves the problems, the existing cover plate disc is not generally used in engineering due to higher requirements on processing technology and cost. The cover plate disc structure with the radial runway inclined hole type receiving hole provided by the invention has the advantages that the hole deflects a certain angle along the disc rotating direction, so that the cover plate disc structure has a proper air inlet angle, more air flows with high rotation ratio from the nozzle outlet can smoothly flow into the receiving hole from the rotating disc cavity, the flow loss inside the hole is reduced, the flow coefficient of the receiving hole is improved by 25.2%, and the improvement of the temperature drop performance of a prerotation system is facilitated. And the cover plate disc with the radial runway inclined hole type receiving hole has a relatively simple structure, has low requirements on processing difficulty and is convenient to be widely used in engineering.

Drawings

FIG. 1 is a schematic diagram of a fluid domain structure of a pre-rotation system with an impeller cover plate.

Fig. 2 is a schematic illustration of a conventional axial racetrack angular hole of 25 ° α ₁ arranged on a cover plate disc along a uniform circumference.

Fig. 3 is a schematic view of radial racetrack ramp 30 ° α ₂ disposed on a coverplate disk along a uniform circumference.

Fig. 4 is a schematic view of the fluid field of the cover plate structure with radial runway inclined hole type receiving holes applied to the prerotation system.

FIG. 5 is a velocity flow diagram of a conventional axial through bore.

Fig. 6 is a velocity flow diagram of a radial racetrack inclined bore receiving hole.

In the drawings

1. An air inlet cavity, 2 a prewhirl nozzle, 3 a prewhirl cavity, 4 a receiving hole, 5 a cover plate cavity, 6 an impeller, 7 a blade air supply hole, 8 a locally enlarged axial runway inclined hole type receiving hole, 9 an axial runway inclined hole type receiving hole inlet section, 10 an axial runway inclined hole type receiving hole outlet section, 11 an axial runway inclined hole type receiving hole flow surface, 12 a locally enlarged radial runway inclined hole type receiving hole, 13 a radial runway inclined hole type receiving hole inlet section, 14 a radial runway inclined hole type receiving hole outlet section, 15 a radial runway inclined hole type receiving hole flow surface, 16 a radial runway inclined hole type receiving hole outlet section, and a radial runway inclined hole type receiving hole outlet section

Detailed Description

The invention will now be further described with reference to the following examples and drawings:

The present embodiment is a cover plate disk with radial racetrack inclined hole receiving holes for use in a pre-swirl gas supply system.