CN112607039A

CN112607039A - Propeller aircraft gap ventilation structure

Info

Publication number: CN112607039A
Application number: CN202011602733.4A
Authority: CN
Inventors: 周红; 董建鸿
Original assignee: Xian Aircraft Design and Research Institute of AVIC
Current assignee: Xian Aircraft Design and Research Institute of AVIC
Priority date: 2020-12-29
Filing date: 2020-12-29
Publication date: 2021-04-06
Anticipated expiration: 2040-12-29
Also published as: CN112607039B

Abstract

The application provides a propeller aircraft gap ventilation structure, ventilation structure includes screw (1), oar cap (2), nacelle skin front end (3), preceding gap (4), engine wall (5), off normal formula reducing gear box (6), blast pipe (7), ejector sleeve pipe (8), ejector gap (9), nacelle skin rear end (10), back gap (11), engine compartment anterior segment (12), engine compartment back end (13), wherein: the paddle cap (2), the deviation type reduction box (6), the engine wall surface (5) and the exhaust pipe (7) are connected in sequence; an engine accessory is arranged above the offset reduction gearbox (6), and the axes of the engine wall surface (5) and the exhaust pipe (7) are positioned below the offset reduction gearbox (6); the front gap (4) is formed by a rotating paddle cap (2) and a static nacelle skin front end (3).

Description

Propeller aircraft gap ventilation structure

Technical Field

The invention belongs to the field of aviation, and relates to a propeller airplane gap ventilation structure.

Background

Compared with a turbofan engine, the propeller-driven aircraft usually adopts a turboshaft engine, wherein (1) the turboshaft engine has no fan outer duct, and the heat of the core flow of the engine is directly transferred to an engine compartment through the wall surface of a casing, so that the heat in the engine compartment is larger; (2) the turbine power of the turboshaft engine needs to overcome the work of the air compressor and drive the rotation of the propeller, so that the pressure of airflow at the inlet of the spray pipe is lower, and the injection effect of main jet flow is weaker. Therefore, it is very important to reasonably design the ventilation air inlet and exhaust of the propeller-driven aircraft.

Disclosure of Invention

The invention aims to provide a propeller-driven aircraft gap ventilation structure which can effectively solve the problem of ventilation and heat dissipation of an engine compartment, does not need to increase the number of ventilation openings and the ventilation area, and does not damage the appearance of an aircraft.

The application provides a propeller aircraft gap ventilation structure, ventilation structure includes screw (1), oar cap (2), nacelle skin front end (3), preceding gap (4), engine wall (5), off normal formula reducing gear box (6), blast pipe (7), ejector sleeve pipe (8), ejector gap (9), nacelle skin rear end (10), back gap (11), engine compartment anterior segment (12), engine compartment back end (13), wherein:

the paddle cap (2), the deviation type reduction box (6), the engine wall surface (5) and the exhaust pipe (7) are connected in sequence; an engine accessory is arranged above the offset reduction gearbox (6), and the axes of the engine wall surface (5) and the exhaust pipe (7) are positioned below the offset reduction gearbox (6); the front gap (4) is a gap formed by the rotating paddle cap (2) and the front end (3) of the static nacelle skin; the front gap (4) is in a step shape with a wide upper part and a narrow lower part, and the injection gap (9) is a gap formed by the exhaust pipe (7) and the injection sleeve (8); the rear gap (11) is a gap formed by the ejector sleeve (8) and the rear end (10) of the nacelle skin.

Specifically, the width of the upper side of the front gap (4) is at least 10mm larger than that of the lower side.

Specifically, the width of the lower side of the front gap (4) is more than or equal to 20 mm.

Specifically, the width of the injection gap (9) is 30-50 mm.

Specifically, the width of the rear gap (11) is 10mm-20 mm.

Specifically, the ejector sleeve (8) is a flexible sleeve, and the exhaust pipe (7) extends into the ejector sleeve (8).

Specifically, the outlet position of the exhaust pipe (7) does not exceed the bending inflection point of the injection sleeve (8).

Specifically, the axial coincidence length of the exhaust pipe (7) and the injection sleeve (8) can ensure that the airflow in the exhaust pipe (7) does not flow backwards.

In summary, the present invention provides a propeller-driven aircraft gap ventilation structure, which forms a ventilation channel of a propeller-driven aircraft by carefully designing the inherent gap of the propeller-driven aircraft and using the gap as an air inlet and an air outlet for ventilation of an engine compartment.

Drawings

FIG. 1 is a schematic illustration of the propeller aircraft slot ventilation structure of the present invention;

FIG. 2 is a schematic view of the front slit of the present invention;

FIG. 3 is a schematic diagram of the exhaust injection of the present invention;

FIG. 4 is a schematic diagram of the rear slot configuration of the present invention;

wherein: 1-propeller, 2-propeller cap, 3-front end of nacelle skin, 4-front gap, 5-engine wall, 6-offset reduction gearbox, 7-exhaust pipe, 8-ejector sleeve, 9-ejector gap, 10-rear end of nacelle skin, 11-rear gap, 12-front section of engine cabin and 13-rear section of engine cabin.

Detailed Description

The propeller is positioned in front of the nacelle, and a clearance exists between the rotating propeller cap and the stationary nacelle, and the clearance is at least larger than the axial offset distance of the propeller when the propeller rotates, but the clearance is not too large so as to avoid increasing the resistance of the nacelle. In addition, other inevitable gaps, such as the gap between the ejector sleeve and the rear section of the nacelle, exist in the assembly process of the airplane. Some gaps cannot be closed, such as the gap between the paddle cap and the nacelle; some gaps, if they can be closed, are at the expense of weight. If the gaps are reasonably utilized and carefully designed to be used as the ventilation openings of the airplane, the number of the ventilation openings can be reduced, damage to the appearance of the airplane is reduced, and the weight of the airplane can be reduced.

As shown in fig. 1, the invention relates to a propeller airplane gap ventilation structure. The ventilation structure includes: the system comprises a propeller (1), a propeller cap (2), a front end (3) of a nacelle skin, a front gap (4), an engine wall surface (5), an offset reduction gearbox (6), an exhaust pipe (7), an injection sleeve (8), an injection gap (9), a rear end (10) of the nacelle skin, a rear gap (11), a front section (12) of the nacelle and a rear section (13) of the nacelle;

as shown in fig. 2, between the rotating paddle cap (2) and the stationary nacelle skin forward end (3) is a forward gap (4) that acts as an engine compartment ventilation air inlet to direct ambient air into the engine compartment forward section (12) under the influence of the propeller slipstream to cool the engine walls (5). The front gap (4) is distributed in a step shape with a wide upper part and a narrow lower part so as to effectively cool accessories on the offset reduction gearbox (6).

As shown in fig. 3, a jet gap (9) is provided between the exhaust pipe (7) and the jet sleeve (8), and serves as an exhaust passage of the engine compartment, and the airflow that cools the engine wall surface (5) is discharged to the front section (12) of the engine compartment by the jet action of the main jet of the engine.

As shown in fig. 4, the ejector sleeve (8) and the rear end (10) of the nacelle skin are rear slits (11) for guiding outside air into the rear section (13) of the nacelle under the action of the aircraft wing to cool the exhaust pipe.

The ventilation structure of the invention makes full use of the inherent gaps of the propeller-type airplane and takes the gaps as the main flow passage for ventilation of the engine compartment, so that the number of ventilation openings is reduced by 50%, the ventilation area is reduced by 80%, the appearance of the airplane is not damaged, and the weight cost for sealing the gaps is avoided.

Claims

1. The utility model provides a screw aircraft gap ventilation structure, a serial communication port, ventilation structure includes screw (1), oar cap (2), nacelle skin front end (3), preceding gap (4), engine wall (5), off normal reducing gear box (6), blast pipe (7), draw and penetrate sleeve pipe (8), draw and penetrate clearance (9), nacelle skin rear end (10), back gap (11), engine compartment anterior segment (12), engine compartment back end (13), wherein:

2. The ventilation structure according to claim 1, characterized in that the width of the upper side of the front slit (4) is at least 10mm greater than the width of the lower side.

3. The ventilation structure according to claim 1, characterized in that the width of the lower side of the front slit (4) is 20mm or more.

4. The ventilation structure according to claim 1, characterized in that the width of the ejection gap (9) is 30mm-50 mm.

5. The ventilation structure according to claim 1, characterized in that the width of the rear slit (11) is 10-20 mm.

6. The ventilation structure according to claim 1, characterized in that the ejector sleeve (8) is a flexible sleeve, and the exhaust pipe (7) extends into the ejector sleeve (8).

7. The ventilation structure according to claim 6, characterized in that the outlet position of the exhaust pipe (7) does not exceed the bending inflection point of the ejector sleeve (8).

8. The ventilation structure according to claim 7, characterized in that the axial coincidence length of the exhaust pipe (7) and the ejector sleeve (8) ensures that the air flow in the exhaust pipe (7) does not flow backwards.