JPS62282190A - Axial compressor - Google Patents

Abstract

PURPOSE:To achieve a high speed and a large capacity by forming two flow path systems symmetrically in a casing and producing a double flow. CONSTITUTION:A casing 1 is splitted symmetrically into first and second casings 1a, 1b and an inlet casing 7 is formed in the center. A stationary blade 8 is secured to the inner circumference of the first and second casings 1a, 1b and a moving blade 9 is secured to the outer circumference of a rotor 2. The air sucked through the inlet casing 7 passes through the flow paths 10a, 10b and produces a double flow. Consequently, the effective length of the moving blade can be shortened resulting in a high speed and a large capacity.

Description

Detailed Description of the Invention 3. Detailed Description of the Invention (Objective of the Invention) (Industrial Application Field) The present invention relates to an axial flow compressor, and in particular, the present invention relates to an axial flow compressor that can achieve high-speed passenger capacity without increasing the effective length of the This invention relates to an axial flow compressor that can be used to

(Prior Art) Axial flow compressors are generally known that sequentially compress intake air within a flow path formed by stator vanes fixed to a casing and rotor blades fixed to a rotor.

FIG. 3 shows a conventional axial flow compressor of this type. In the figure, reference numeral 31 indicates a casing, a stationary blade 32 is fixed to the inner periphery of this casing 31, and a moving blade 34 is fixed to the outer periphery of a row 933 incorporated in the casing 31.

The rotor 33 has both ends connected to a first holder 35 and a second 1111 holder 35.
3J, and the outside of the second bearing 36 is supported by a thrust bearing 37. J3, numeral 39 indicates a discharge casing.

This structure has a flow path 40 formed by a stator blade 32 and a rotor blade 34.
Since it is one series, it is hereinafter referred to as single flow type.

Incidentally, in recent years, there has been a strong tendency for axial flow compression chambers to increase in speed and capacity, and in single flow systems, it is required to increase the effective length of the rotor blades 34 in order to increase the inlet flow rate.

When the effective length is increased, the Matsuha number of the rotating blade increases and the efficiency of the axial flow compressor decreases.

Conventionally, the NAC 80 type airfoil has been widely used as an airfoil suitable for compression rows, but as shown in Figure 4, losses occur when the Matsuh number exceeds 0.76. The coefficient increases dramatically. On the other hand, in order to increase the high-speed Hitoyoshi capacity of axial flow compressors, the development of airfoils that can achieve high efficiency of 1q even with a high Matsuha number is underway. Not completed.

(Problems to be Solved by the Invention) Therefore, in order to increase the speed and capacity of the axial flow compressor, it is necessary to improve the effective length of the a-blade, and as a result, the efficiency of the compressor decreases. There was a problem.

Furthermore, there is a problem in that increasing the effective length increases centrifugal stress and reduces reliability.

Furthermore, as the thrust force increases with the increase in capacity, it is necessary to increase the size of the thrust bearing 37, which increases the circumferential speed of the thrust tip and increases the thrust force. There was also the problem of a decline in 0.

15, it is also conceivable to form the rotor blade 34 with a high-grade material such as titanium or to increase the cross-sectional area of 92, but problems such as increased manufacturing cost and manufacturing restrictions remain.

Therefore, an object of the present invention is to provide an axial flow compression chamber that can achieve high speed and large capacity without improving the effective length of the rotor blades, by solving the above-mentioned problems of the conventional technology. It is in.

[Structure of the invention]

(Means for Solving the Problems) In order to achieve the above object, the present invention provides a means for discharging intake air within a flow path formed by stationary blades fixed to a casing and moving blades fixed to a rotor. The axial flow compressor is characterized in that two series of the flow passages are formed symmetrically within the casing, and the fluid flow is of a double flow type.

(Function) To explain the present invention in detail based on the above configuration, the fluid sucked into the casing is divided into two flow paths formed in the flow path, and is sequentially compressed in each flow path. Ru.

Compared to the conventional single-flow type, which is a double-flow type, the area of each flow path can be reduced, and the effective length of each rotor blade can be shortened. As a result, the blade number can be kept low and a reduction in compression efficiency can be prevented. Further, since the flow passages are formed symmetrically, the pressure of the fluid is balanced, the thrust force is reduced, and the thrust bearing can be made smaller.

(Example) An example of an axial flow pressure machine according to the present invention will be described below with reference to FIG.

In FIG. 1, reference numeral 1 indicates a casing, and a rotor 2 is rotatably incorporated into the casing 1. The rotor 2 is supported at both ends by a first bearing 3 and second bearings 3 and 4, and the outside of the second bearing 4 is supported by a thrust bearing 5.

The casing 1 includes a first casing 1a and a second casing 1.
b, and are formed symmetrically on the left and right, with an entry casing a formed in the center. Stator blades 8 are fixed to the inner circumferences of the first and second casings 1a, "It", respectively, and rotor blades 9 are fixed to the outer circumference of the rotor 2 symmetrically.

In the 1N1 flow compressor configured in this manner, the air t taken in from the inlet casing a is
The liquid flows into the casings 1a and 1b separately, passes through channels 10a and 1Ob formed by static V-shaped rotor blades 9, and is sequentially compressed. Since this structure has two lines of flow paths 10a and 10b, it is hereinafter referred to as a 1u flow type.

Therefore, according to the present invention, by using a reciprocating type and a lifting platform with equal inlet flow rates, the effective length of the dynamic 9 can be reduced to approximately half that of the conventional single flow type. . As a result, the number of mats of the turret can be kept low, and compression-like efficiency reduction can be prevented. In addition, each flow path 1
Since the pressure of the fluid compressed by 0a and 10b is balanced on the left and right sides, the thrust force is reduced, and the thrust bearing 5 can be made extremely small.

On the other hand, FIG. 2 shows another embodiment of the present invention. According to this embodiment, inlet casings (not shown) are formed at both ends of the casing 1, and a discharge casing 12 is formed in the center. Even with this configuration, it is possible to use a return flow type, and since the pressures of the left and right fluids are balanced, the same effect as described above can be obtained.

〔Effect of the invention〕

As is clear from the above explanation, since the present invention is a reciprocating type, the effective length of the moving shaft can be shortened, improving the efficiency and reliability of the axial flow compressor, and improving the thrust bearing. It is possible to achieve miniaturization.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional view showing an embodiment of an axial flow compressor according to the present invention, Fig. 2 is a longitudinal sectional view showing an embodiment of the same, and Fig. 3 is a longitudinal sectional view showing a conventional axial flow compressor. FIG. 4 is a Poss diagram showing the relationship between the Matsuha number and the decay coefficient. DESCRIPTION OF SYMBOLS 1... Casing, 2... Rotor, 5... Thrust bearing, 8... Stationary blade, 9... Moving part, 10 a, 1
0 'o...'ot road. Applicant's representative Sato - Male 1st eye 2nd figure 3rd eye 4th decoy

Claims (1)

[Claims] 1. In an axial flow compressor that sequentially compresses intake air within a flow path formed by stator blades fixed to a casing and moving blades fixed to a rotor, An axial flow compressor characterized in that two series of the flow passages are formed symmetrically on the left and right sides, and the fluid flow is of a double flow type. 2. The axial flow compressor according to claim 1, wherein an inlet casing is formed in the center of the casing. 3. The axial flow compressor according to claim 1, characterized in that a discharge casing is formed in the center of the casing.