JP2691051B2 - Gas turbine engine for aircraft - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an inlet particle separator (hereinafter
The present invention relates to an aircraft gas turbine engine having an IPS) and an infrared blocking device (hereinafter referred to as IRS).

[Prior Art] In aircraft engines of recent years, there is a tendency to install IPS to prevent erosion inside the engine due to dust and the like contained in intake air. With the increase, the thinning of blades, the reduction of chips and clearances, the effect of erosion on engine performance becomes large, and the overhaul cost also increases.

In addition, in order to improve stealth, it is necessary to lower the temperature of high-temperature exhaust gas and engine surface temperature, and there is an increasing need to attach it to IRS.

As shown in Fig. 4, the IPS applied to the conventional aircraft engine is the IPS blower in which the intake 09 sucked into the IPS01 contains the intake 010 to the engine main body 07 and the dust inside the IPS01.
Intake to 02 is separated into 011 and intake to the engine body 010
Goes into the engine body 07 through the intake duct 06, and IPS
The intake air 011 to the blower 02 is sucked by the IPS blower 02 driven via the extension drive shaft 08 by the blower drive gear 05 provided in the accessory gear box 04, and the exhaust air 012 thereof is discharged to the atmosphere. Met.

Further, the conventional IRS03 has a secondary air 013 due to the ejector effect of the exhaust gas 014 of the engine body 07 as shown in FIG.
To cool the surface of the exhaust duct forming IRS03.

[Problems to be solved by the invention]

 The conventional device has the following problems.

(1) The IPS blower is driven at about 30,000 rpm, but the output extraction part of the auxiliary gearbox is normally decelerated to several thousand rpm, so it is necessary to add a speed increasing gear for the IPS blower.

(2) Generally, the accessory gearbox is IPS in front of the engine.
Since the blower is placed rearward, an extension drive shaft and bearing are required. Further, since the intake duct is arranged at the rear part of the accessory gear box, the extension drive shaft needs to penetrate the intake duct. Further, as shown in FIG. 4, in a twin-engine helicopter that uses a single-intake type intake duct, the IPS blower mounting positions are opposite between the right engine and the left engine, and thus the compatibility of the drive device is lost.

(3) The diameter of the IPS blower is about 1/2 of the engine diameter, but a large front room engine room is required to place the IPS blower on the outer periphery of the engine body.

(4) IR that cools the wall of the exhaust duct inner cylinder (tail cone) only by introducing secondary air due to the ejector effect
In S, it is necessary to increase the flow velocity of the mainstream gas at the IPS inlet in order to obtain a sufficient ejector effect against the pressure loss at the strut that becomes the introduction passage, and avoid lowering the cycle efficiency as an axial power type engine. I couldn't do it.

The present invention is intended to realize a gas turbine engine that solves the above problems.

[Means for solving the problem]

The present invention forms an engine exhaust flow path between a tail cone having a slit and an outer cone provided on the outer side of the tail cone, and an inlet particle coupled to the engine output shaft at the front portion inside the tail cone. A gas turbine engine is characterized in that a blower for a separator is provided, and a duct that guides air containing sand separated from intake air for combustion to the blower for an inlet particle separator is provided.

[Action]

In the above, the air containing the dust sent from the inlet particle separator is sucked by the blower for the inlet particle separator directly connected to the output turbine shaft through the duct, and is discharged as cooling air into the tail cone of the infrared cutoff device. . The cooling air discharged into the tail cone flows out in the form of an air film into the engine exhaust flow path from a slit provided in the tail cone, lowers the surface temperature of the tail cone and blocks infrared radiation.

Due to the above, the extension drive shaft used in the conventional device is not required, so it is possible to reduce the number of parts, weight and cost, improve reliability and maintainability, and mount a blower on the outer periphery of the engine body. Since it is not necessary, the high-speed flight performance of the aircraft is improved, and since the secondary air taken into the outer cone can be reduced, the engine exhaust can be decelerated sufficiently and the performance of the infrared cutoff device is improved. Not only can it be achieved, but high engine cycle efficiency can be maintained.

〔Example〕

An embodiment of the present invention will be described with reference to FIGS.

The present embodiment shown in FIGS. 1 to 3 comprises a tail cone 2a having a slit 13 and an outer cone 2b provided outside the tail cone 2a and having a secondary air intake port 14 at the rear of the engine body 5. The IRS2 provided, the impeller 12a of the IPS blower provided at the front part inside the tail cone 2a, which is connected to the rear end of the output turbine shaft 5b to which the output turbine blade 5a in the engine body 5 is connected, and the impeller 12a The IPS blower outlet guide vanes 12b provided at the rear and the IPS1 provided at the side of the engine body 5 are connected at one end to air 8a containing dust and the like from the other end and exhausted at the front of the IRS2. The IPS duct 8 is provided to supply the impeller 12a through the frame 16.

In the above, intake 7 to the engine body 5 by IPS1
The air 8a containing the dust separated from the air passes through the duct 8 and the exhaust frame 16 and is guided to the impeller 12a of the IPS blower behind the output turbine blade 5a. The IPS blower impeller 12a is mounted directly on the output turbine shaft 5b,
Rotating at about 30,000 rpm, the cooling air 15 is sent out into the tail cone 2a of the IRS 2 via the outlet guide vanes 12b. The cooling air 15 sent into the tail cone 2a is supplied to the engine exhaust 17a through a large number of slits 13 provided in the tail cone.
Flows into the mainstream gas passage (engine exhaust flow path) 1717 in the form of an air film, lowers the surface temperature of the tail cone, and blocks infrared radiation.

The rotation speed of the impeller 12a of the above IPS blower is about 30,000 rp
m is appropriate, on the other hand, the rotation speed of the output turbine blade 5a is about 30,000 rpm, and the size of the IPS blower can be designed to fit within the output turbine exhaust passage inner diameter. Exhaust air flow rate is IRS tail cone 2
Since the flow rate is necessary and sufficient for cooling a, the method according to this embodiment is practically sufficient.

2 and 3, the duct 11 for the oil cooler is provided between the oil cooler 10 and the exhaust frame 16. This is because the impeller 12a of the IPS blower built in the tail cone 2a is different from the IPS1. In addition, exhaust air 11a from the air-cooled oil cooler 10 is also sucked as cooling air 15. When the engine of this embodiment is used as a twin-engine helicopter engine, the right engine and left engine are IPS1 and oil cooler.
The left and right can be interchanged by simply exchanging the 10 mounting positions, and consideration is given to the compatibility of all parts.

Due to the above, parts such as auxiliary gearbox output extraction part drive gear, extension drive shaft and bearing, which are necessary for IPS blower drive in the conventional device, are unnecessary, and the number of parts, weight,
It is possible to reduce costs, improve reliability and maintainability. In a twin-engine helicopter that uses a single-suction intake duct, there is no restriction on the drive shaft of the IPS blower, so compatible IPS can be designed for the left and right engines. Also,
Since there is no need to install an IPS blower on the outer periphery of the engine body, the engine room can be compactly assembled, and especially the front area can be reduced, improving the high-speed flight performance of the aircraft. Furthermore, since the tail cone wall surface can be sufficiently cooled by the exhaust of the IPS blower, the introduction of secondary air due to the ejector effect can be reduced, and the main flow can be sufficiently decelerated (static pressure recovery) in the exhaust duct. Not only can the IRS performance be improved, but the cycle efficiency of the shaft output engine can be maintained high.

〔The invention's effect〕

The gas turbine engine for aircraft of the present invention is IPS by an IPS blower directly connected to the output turbine shaft of the engine body.
By sucking air containing dust from the air, discharging it into the tail cone of the IRS and cooling the wall surface of the tail cone,
Since the extension drive shaft used in the conventional device is unnecessary, the number of parts, weight and cost can be reduced, reliability and maintainability can be improved, and there is no need to install a blower on the outer periphery of the engine body. Therefore, the high-speed flight performance of the aircraft is improved, and the secondary air sucked into the outer cone can be further reduced, so that the engine exhaust can be sufficiently decelerated and the performance of the infrared cutoff device can be improved. In addition, high engine cycle efficiency can be maintained.

[Brief description of the drawings]

FIG. 1 is an explanatory view of an embodiment of the present invention, FIG. 2 is an explanatory view in the case where an oil cooler duct is additionally provided in the above embodiment, and FIG. 3 is III-III of FIG. FIG. 4 and FIG. 4 are explanatory views of a conventional device. 1 ... IPS, 2 ... IRS, 2a ... Tail cone, 2b ... Outer cone, 3 ... Auxiliary gearbox, 4 ... Intake duct, 5 ... Engine body, 5a ... Output turbine blade, 5b ...... Output turbine shaft, 7 ... Intake to the engine body, 8 ... IPS duct, 8a ... Air containing dust, 9 ... Exhaust, 10 ... Oil cooler, 11 ... Oil cooler duct, 11a …… Oil cooler exhaust, 12a …… Impeller, 12b …… Outlet guide vane, 13 …… Slit, 14 …… Secondary air intake, 14a …… Secondary air, 15 …… Cooling air.

Continuation of the front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location F41H 11/02 F41H 11/02

Claims (1)

(57) [Claims] An engine exhaust passage is formed between a tail cone having a slit and an outer cone provided outside the tail cone, and an inlet connected to an engine output shaft at a front portion of the tail cone. A gas turbine engine, comprising a blower for a particle separator, and a duct for guiding air containing dust separated from intake air for combustion to the blower for an inlet particle separator.