JP2003056361A - Turbofan jet engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce various losses caused during filling into a turbofan jet engine and smooth a flow of air flowing in an outside outer wall of a cowling of the turbofan jet engine. SOLUTION: A suction opening 21 of an intake passage is tubularly formed so as to guide combustion air or air to be sucked and filled into the engine 11 via a low pressure compressor 13 into the engine 11. A swirl of the combustion air or air is generated and sucked and filled into the engine 11 by spirally providing a radially inward protruding swirl vane 30 along an inner wall part 21 of the suction opening of the intake passage. In the outer wall of an outer side front face of the cowling 12 housing the engine 11, the flow of air flowing in the outside outer wall of the cowling 12 is smoothly discharged to the rear by spirally providing a radially outward protruding swirl vane 35 along an outer wall part of the outside front face of the cowling 12.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a turbofan jet engine, and more particularly, to an improved structure of a suction port for introducing propulsion air of a turbofan jet engine and an improved structure of an outer wall portion of a cowling for reducing air resistance. It is about.

[0002]

2. Description of the Related Art A turbofan jet engine for an aircraft uses propeller blades attached to the front of a compressor to accelerate the air taken in from the front by accelerating the air taken in from the air intake on the front of the engine. Send compressed air. A part of this accelerated flow of air is further compressed by the compressor, and then is mixed with jet fuel in the combustion chamber as compressed air and burned. The high-temperature and high-pressure exhaust gas generated by this combustion is passed through the turbine. At this time, the turbine is driven by the high-temperature and high-pressure exhaust gas to obtain the driving force of the series of compressors, and then the exhaust gas is violently ejected to the rear of the engine to obtain the propulsion force. On the other hand, the structure is such that the remaining accelerated compressed air that has not passed through this series of combustion strokes is ejected from the engine through a bypass.

[0003]

In the turbofan jet engine for an aircraft having such a structure, the air sucked by the low pressure compression fan in the engine is almost immediately after flowing into the low pressure compression fan. Converted to a right angle. The gas that was flowing smoothly to the suction port of the low-pressure compression fan, together with the fact that the flow direction of the gas was greatly changed in this way, when flowing into the low-pressure compression fan, it is temporarily turbulent due to the rotation of the low-pressure compression fan. It becomes a state. For this reason, loss of flow velocity, pressure, etc. occurs due to the gas resistance, and these various losses have been factors that reduce the efficiency of filling air into the engine.
In addition, the air flowing outside the cowling is stagnant in the vicinity of the cowling and an air boundary layer is generated to reduce the peelability. The decrease in the peelability due to the generation of the boundary layer of air near the cowling leads to an increase in the air resistance to the engine itself including the cowling. Therefore, regarding the fluidity of air in a turbofan jet engine, it is possible to reduce the occurrence of a boundary layer of the air with respect to the combustion air that flows in the engine and the compressed air or the flowing air that flows outside the cowling, and to obtain good air separation. There is a need to reduce the resistance.

Therefore, an object of the present invention is to reduce various losses that occur when the combustion air and the compressed air suction-filled through the low-pressure compression fan in the turbofan jet engine flow into and fill the turbine in the engine. To provide a suction port structure for an intake system of a turbofan jet engine, swirl vanes for generating swirl flow in the combustion air and compressed air immediately before being suction-filled through the low-pressure compression fan are provided. In addition, the front surface of the outer outer wall of the cowling is reduced in order to reduce the occurrence of an air boundary layer in the vicinity of the cowling with respect to the flowing air flowing on the outer outer wall of the cowling accommodating and storing the turbofan jet engine and to improve the air separation property. A turbo fan jet with swirl vanes that generate swirl flow There is provided an outer exterior wall of the cowling of the engine.

[0005]

According to a first aspect of the present invention, a plurality of compression turbofan equipments having different compression pressures for introducing outside air for generating propelling air into an engine or a combustion chamber and the compression are provided. A plurality of drive turbine equipment driven by high-pressure combustion gas for driving the turbofan equipment, and a series of combustion equipment including equipment for supplying fuel to the combustion chamber by fuel supply means and combustion chamber equipment In a turbofan jet engine provided with a cowling for accommodating the series of combustion equipment, air sucked into the engine or the combustion chamber is introduced into a suction port portion in front of a low pressure compression fan in the turbofan jet engine. A swirl vane protruding inward in the radial direction of the suction port on the front surface of the low-pressure compression fan, By spirally providing along the inner wall of the suction port of the engine, the air sucked into the low-pressure compression fan in the engine can be swirled while flowing into the low-pressure compression fan in the engine. Is characterized by.

According to the above invention, when the combustion air or the compressed air sucked through the low pressure compression fan in the turbofan jet engine flows through the suction port portion in front of the low pressure compression fan, it is in front of the low pressure compression fan. The combustion air or compressed air in the vicinity of the inner wall of the suction port is bent in the rotational direction along the spiral swirl vanes and flows as a swirl flow. At this time, a flow component in the circumferential direction is given to the combustion air or the compressed air, and the combustion air or compressed air gradually turns in the circumferential direction. Due to the action of the swirl vanes, a swirling flow in the same rotation direction as the low pressure compression fan is generated in the combustion air or compressed air flowing through the suction port. Then, the combustion air or compressed air that has reached the low-pressure compression fan while swirling by this swirling flow flows into the turbofan jet engine by the rotation operation of the low-pressure compression fan, and the swirling flow is not eliminated even in the engine. Powerful compressed air is generated by each compression fan.

According to a second aspect of the present invention, in addition to the configuration of the first aspect, the height of the swirl vane up to the projecting end is
It is characterized in that it is formed so that it gradually becomes higher from a position far from the low-pressure compression fan toward the low-pressure compression fan.

According to the second aspect of the invention, the height of the swirl blade gradually increases as it approaches the low-pressure compression fan, and becomes maximum immediately before the low-pressure compression fan. Therefore, the magnitude of the swirling flow generated at the suction port is also , It gradually increases as it approaches the low-pressure compression fan, and becomes maximum immediately before the low-pressure compression fan. On the other hand, if the height of the swirl vanes is increased, the resistance of the combustion air or the compressed air sucked into the engine to the gas increases, and the degree of flow velocity loss tends to increase. However, by configuring the swirl vane as described above, the swirl flow can be effectively generated near the low pressure compression fan while suppressing the loss of the flow velocity as much as possible.

According to a third aspect of the present invention, in addition to the configuration of the first or second aspect, the twist angle of the swirl vane with respect to the axial direction of the inlet part is located far from the low pressure compression fan. Is characterized in that the swirl vanes are provided so that the swirl vanes gradually increase as they approach the low-pressure compression fan.

According to the third aspect of the present invention, the swirl angle of the swirl blade gradually increases as it approaches the low-pressure compression fan, and reaches its maximum immediately before the low-pressure compression fan. Further, it gradually increases as it approaches the low-pressure compression fan, and becomes maximum immediately before the low-pressure compression fan. On the other hand, when the twist angle of the swirl vane is increased, the gas due to the combustion air or the compressed air flowing along the swirl vane has a larger velocity component in the circumferential direction, but on the other hand, in the axial direction of the intake port of the engine intake passage, The velocity component is reduced accordingly. However, when the swirl vanes are configured as described above, swirl flow is effectively generated near the low pressure compression fan.

According to a fourth aspect of the present invention, in addition to the structure of the third aspect, the side surface portion of the swirl vane is inclined from the radial direction of the suction port portion toward the rotational direction side of the swirl flow. In addition, the swirl vane is provided.

According to the fourth aspect of the invention, the swirl vanes inclined to the rotational direction side of the swirl flow generate a swirl flow in the gas by the combustion air or the compressed air, and the gas by the combustion air or the compressed air. Is guided so as to flow in the axial center direction from the vicinity of the inner wall of the suction port. As a result, the swirling flow is effectively generated even in the vicinity of the axial center of the suction port portion before the low-pressure compression fan in which the swirling blade does not directly act. Further, generally, the flow velocity of the gas flowing through the pipe line is smallest in the inner wall portion, increases with increasing distance from the inner wall portion, and tends to become maximum near the axial center. However, since the swirl vane configured as described above guides the gas due to the combustion air or the compressed air near the inner wall portion of the pipeline having the slow flow velocity to the vicinity of the axial center where the flow velocity is faster, The flow of the whole gas by combustion air or compressed air becomes smoother.

According to a fifth aspect of the invention, in addition to the structure of the fourth aspect of the invention, the cross-sectional shape of the swirl vane perpendicular to the axial direction of the suction port is from the projecting end of the swirl vane. It is characterized in that it is formed so that it gradually widens as it approaches the inner wall of the suction port.

According to the fifth aspect of the present invention, the swirl vane is formed so that its cross-section is widened toward the end, so that the strength of the swirl vane itself and its mounting strength are sufficiently secured, and a relatively easy method such as casting is performed. Integral formation is possible.

According to a sixth aspect of the present invention, a plurality of compression turbofan facilities having different compression pressures for introducing outside air for generating propulsion air into the engine or the combustion chamber and the compression turbofan facility are driven. In order to provide a plurality of drive turbine equipment driven by high-pressure combustion gas, a series of combustion equipment including equipment for supplying fuel to a combustion chamber by a fuel supply means and a combustion chamber equipment, and the series of combustion equipment In a turbofan jet engine having a cowling for accommodating the engine, a swirl vane protruding radially outward of the cowling is provided spirally along an outer wall portion of the cowling on an outer front surface of the cowling. As a result, the air flowing along the outer wall of the cowling is swirled to the rear of the engine. It is characterized by a configuration such that out.

According to the sixth aspect of the invention, when the air flowing along the outer periphery of the cowling which houses and stores the turbofan jet engine flows on the front surface of the cowling, the air near the outer wall portion of the cowling has a spiral shape. It is bent in the direction of rotation along the swirl vane of and flows as a swirl flow.
At this time, a flow component in the circumferential direction is given to the air near the outer wall portion of the cowling, and the air gradually turns in the circumferential direction. Due to the action of the swirl vanes, swirl flow in the same rotation direction as the low pressure compression fan in the engine is generated in the air flowing near the outer wall portion of the cowling. And
While swirling by this swirling flow, air is discharged to the rear of the turbofan jet engine without generating a boundary layer.

According to a seventh aspect of the present invention, in addition to the structure of the sixth aspect, the height of the cowling from the outer end of the cowling to the tip of the swirl vane is set. It is characterized in that it is formed so that it gradually increases from the front to the rear of the cowling.

According to the seventh aspect of the present invention, the height of the swirl vanes installed on the outer wall portion outside the cowling gradually increases toward the end point of the swirl vane behind the cowling, and reaches the maximum at the end point of the swirl vane. Therefore, the magnitude of the swirling flow generated on the front surface of the cowling also gradually increases at the end point of the swirl vane behind the cowling and reaches the maximum at the end point of the swirl vane behind the cowling. On the other hand, when the height of the swirl vanes is increased, the air swirled on the front surface of the cowling tends to be turbulent due to a difference in airflow between the air and the surrounding air. However, by configuring the swirl vanes as described above, the swirl flow can be effectively generated while suppressing the turbulent flow as much as possible.

According to an eighth aspect of the present invention, in addition to the configuration of the sixth aspect, the height of the swirl vanes installed on the outer wall of the cowling up to the projecting end is equal to the end of the swirl vanes. It is characterized in that the height of the swirl vane is set to the maximum peak before the point, and then the height of the swirl vane is gradually reduced.

According to the eighth aspect of the invention, the height of the swirl vanes installed on the outer wall portion outside the cowling reaches the maximum peak of the swirl vanes before the end point of the swirl vanes, and thereafter the swirl vanes have a maximum height. The height is gradually decreasing. On the other hand, when the height of the swirl vanes is increased, the air swirled on the front surface of the cowling tends to be turbulent due to a difference in airflow between the air and the surrounding air. However, by configuring the swirl vanes as described above, the swirl flow can be effectively generated while suppressing the turbulent flow as much as possible.

In a ninth aspect of the present invention, in addition to the configuration of the sixth, seventh, or eighth aspects, the twist angle of the swirl vanes installed on the outer wall of the cowling is:
It is characterized in that the swirl vanes are provided so as to gradually increase from the front surface of the cowling toward the rear of the cowling.

According to the ninth aspect of the invention, since the twist angle of the swirl blade gradually increases toward the rear of the cowling and reaches the maximum at the end point of the swirl blade, the magnitude of the swirl flow generated at the front surface of the cowling is large. Again, it gradually increases at the end of the swirl vane and reaches a maximum at the end of the swirl vane. On the other hand, if the twist angle of the swirl vane is increased, the gas due to the air flowing along the swirl vane has a larger velocity component in the circumferential direction, but on the other hand, the resistance to the surrounding air is correspondingly increased, and a difference in air flow occurs. Tends to be turbulent. However, by configuring the swirl vanes as described above, the swirl flow can be effectively generated while suppressing the turbulent flow as much as possible.

The tenth invention according to claim 10 is the ninth invention.
In addition to the configuration of the invention described above, the swirl vane is provided by inclining a side surface portion of the swirl vane installed on an outer wall portion outside the cowling from a radial direction of the cowling toward a rotation direction side of a swirl flow. It is characterized by that.

According to the tenth aspect of the invention, the swirl vanes tilted in the direction of rotation of the swirl flow generate swirl flow in the air flowing around the outer wall of the cowling, and the air flowing around the outer wall of the cowling is cowled. Guide the flow from the vicinity of the outer wall to the rear of the cowling.
As a result, a swirling flow is effectively generated even in the surrounding air where the swirl blade does not directly act, although it is weak. Further, generally, when a swirl flow is generated, the swirl flow tends to be less likely to occur toward the outside. But,
The swirl vane configured as described above guides the swirl flow to the swirl flow even though it is weak against the surrounding air, so that the flow of the entire gas flowing around the cowling becomes smoother.

The eleventh aspect of the present invention is, in addition to the configuration of the tenth aspect of the present invention, that the cross-sectional shape of the swirl vanes is the same as that of the swirl vanes installed on the outer wall portion outside the cowling. It is characterized in that it is formed so that it gradually widens as it approaches the outer wall of the cowling from the tip of the swirl blade.

According to the tenth aspect of the invention, the swirl vane is formed so that its cross-section is widened toward the end, whereby the strength of the swirl vane itself and its mounting strength are sufficiently secured, and a relatively easy method such as casting is performed. Integral formation is possible.

[0027]

BEST MODE FOR CARRYING OUT THE INVENTION (First Embodiment) Hereinafter, the first to fifth inventions will be described with reference to a turbojet engine (hereinafter engine).
Intake combustion air or air into the engine at
An embodiment embodied in an intake passage inlet of a compressed engine will be described with reference to the drawings. FIG. 1 is a cross-sectional view showing the main part of the engine according to the first embodiment.
FIG. 6 is a side sectional view showing an intake passage section taken along a line YY.

As shown in FIG. 1, the basic structure of a turbojet engine 11 (hereinafter referred to as an engine) of this embodiment is composed of three components: a compressor, a combustion chamber and a turbine. Air entering from the front of the engine 11 passes through a low-pressure compressor 13 in the engine, and a part of the air is used as combustion air to be compressed by a series of compressors by a medium-pressure compressor 14 and then a high-pressure compressor 15 to form a combustion chamber. Enter 16. When fuel is injected into the combustion air in the combustion chamber 16, the fuel is burned at once and high temperature and high pressure combustion gas is generated. The high-temperature and high-pressure combustion gas rotates the turbine to actuate the compressor as a driving force, and violently ejects to the rear of the engine to become a propulsive force. As the turbine, a high pressure turbine 17, a medium pressure turbine 18, and a low pressure turbine 19 are installed in this order from the combustion chamber. On the other hand, other compressed air that has passed through the low-pressure compressor 13 in the engine 11 and is not introduced into the combustion chamber 16 is ejected as bypass air to the rear of the engine 11 and merges with the high-temperature and high-pressure combustion gas ejected from the low-pressure turbine 19 to form a jet together. It is ejected as the driving force of the engine. In the engine 11 having these configurations,
The combustion air sucked into the suction port portion 21 of the intake passage in front of the low-pressure compressor 13 in the engine 11 generates a swirl in the combustion air flowing into the suction port portion 21 of the suction port portion 21 so as to generate a swirl. A spiral inlet type intake port is provided in a suction port portion 21 formed in a tubular shape so as to lead from the portion 21 to the low pressure compressor 13. A low pressure compressor 13 is installed at the end of the spiral inlet type intake port.

Next, the construction of the suction port portion 21 of the intake passage, which is a characteristic part of the present invention, will be described in detail. FIG. 2 is a partial perspective view showing a suction port portion of the intake passage cut along line Y-Y in FIG. 1, and FIG. 3 (A), (B),
FIG. 4C is a diagram schematically showing one of the swirl vanes 30 provided in the intake port portion 21 of the intake passage, in the directions of arrows A, B, and C, respectively, and FIGS. 4 and 5 show the intake passage. It is sectional drawing of the suction opening part 21 of FIG.

As shown in FIG. 2, the intake port 21 of the intake passage is formed in a tubular shape so as to guide the combustion air or air into the engine 11, and the end thereof is connected to the low pressure compressor port 13. By operating the low-pressure compressor 13 in the engine 11, combustion air or compressed air is supplied to the engine 11. A plurality of (six in the figure) swirl vanes 30 are provided at regular intervals on the inner wall of the suction port 21 of the intake passage. Each swirl vane 30 has a swirling direction along the inner wall of the intake port 21 of the intake passage so that the combustion air or air flowing in the direction of the arrow F through the intake port 21 of the intake passage swirls in the R direction. It is bent to R and provided in a spiral shape.

As shown in FIGS. 3A to 3C, the swirl vane 30 is formed in a complicated twisted vane shape. Swirl blade 3
0 means that the height from the inner wall portion of the suction port portion 21 of the intake passage to the projecting end portion 32 gradually increases in the direction of the arrow F, that is, as it approaches the low pressure compressor 13 from a position far from the low pressure compressor 13. Is formed as. Further, the swirl vane 30 is configured such that the twist angle α with respect to the axial direction of the suction port portion 21 of the intake passage gradually increases in the direction of the arrow F, that is, as it approaches the low pressure compressor 13 from a position far from the low pressure compressor 13. Is provided. Furthermore, the swirl vane 30
Is provided so that the position of the projecting end portion 32 is inclined from the radial direction of the intake port portion 21 of the intake passage along the turning direction R by an inclination angle β so that the side surface portion 31 is inclined.

Next, the operation and effect of the suction port portion 21 of the intake passage configured as described above will be described.

Combustion air or air sucked by the operation of the low-pressure compressor 13 is guided to the front surface of the low-pressure compressor 13 through the suction port portion 21 of the intake passage. At this time, a part of the combustion air or air flowing near the inner wall of the suction port 21 of the intake passage is swirl vane 3
It hits the side surface portion 31 of 0 and flows along the side surface portion 31 of the swirl vane 30 provided in a spiral shape. As a result, a flow component in the circumferential direction R is given to the combustion air or air,
It gradually turns in the circumferential direction R. And
The combustion air or air that has reached the front surface of the low-pressure compressor 13 as a swirl flow flows into the engine 11 while maintaining the swirl flow when the low-pressure compressor 13 rotates. When combustion air or air flows into the engine 11 in a normal engine, a swirling flow loss is generated due to the influence of pressure and the like in the engine.
However, such a loss can be reduced to some extent by giving a swirling flow to the combustion air or the air in advance so that the air flows into the engine 11 as in the present embodiment.

Further, the suction port portion 21 of the intake passage is actually used.
Combustion air or air flowing through is rarely rectified. Especially low pressure compressor 13
Immediately before the combustion air or air flows into the engine 11 due to the operation of, the turbulent flow becomes temporarily violent in the vicinity of the low-pressure compressor 13. Due to the air flow resistance due to this turbulent flow, various losses such as flow velocity and pressure occur. It is believed that However, in the present embodiment, the swirl blade 3
Since the action of giving a swirling flow of 0 gives the flow directionality, it is possible to eliminate a severe turbulent state or to alleviate its degree.

Further, the swirl flow can be effectively generated by configuring the swirl vanes 30 as described above. That is, the height of the swirl vane 30 gradually increases as it approaches the low-pressure compressor 13,
Moreover, since the twist angle α of the swirl vanes 30 gradually increases as the swirl vanes 30 approach the low pressure compressor 13, the size of the swirl vanes 30 is maximized in front of the low pressure compressor 13 while suppressing the influence of the flow velocity loss by the swirl vanes 30 as much as possible. A swirling flow can be generated as described above.

Furthermore, since the swirl vane 30 is provided with an inclination angle β, the flow of fluid near the inner wall of the suction port 21 of the intake passage is directed toward the axial center of the swirl vane. A swirling flow can be generated near the axis center where the action of the blades 30 does not directly affect. Further, since the gas near the inner wall of the suction port 21 of the intake passage having the low flow velocity is guided to the vicinity of the axial center where the flow velocity is higher, the flow of the entire fluid in the suction port of the intake passage is made smoother. be able to.

As described above, according to the intake port structure 21 of the intake passage of the engine of the present embodiment, the swirling flow of gas immediately before the combustion air or the air flows into the engine 11 by the operation of the low pressure compressor 13. By generating, it is possible to reduce various losses that occur at that time, and thus it is possible to improve the efficiency of filling the inflow air into the engine 11.

The intake passage structure 21 of the engine of the present invention is not limited to the above embodiment,
Modifications can be made without departing from the scope of the claims. For example, the following configuration can be adopted.

The conditions such as the size and shape of the swirl vanes 30, or the number and location of the swirl vanes 30 can be changed as appropriate, and the type of engine, the inner diameter of the intake passage, the swirl flow strength,
It may be designed so as to obtain an optimum flow (swirl flow) depending on the situation. For example, as shown in FIG. 5, the swirl vane 30 may be formed so that its cross section has a substantially triangular shape.
In this case, since a half-closed space does not occur on the back side of the swirl vane 30, the gas that has flowed around to the back side of the swirl vane 30 stays there, and a state occurs that impedes the smooth flow of the entire gas. Can be avoided. Further, when the swirl vane 30 has such a shape, the strength of the swirl vane 30 itself and its mounting strength increase,
The swirl vane 30 and the intake passage 21 can be integrally formed by a method such as casting.

(Second Embodiment) Next, a sixth to tenth aspects of the present invention will be described in a cowling 12 for accommodating an engine 11, which is a series of combustion equipment in a turbojet engine (hereinafter referred to as an engine). An embodiment embodied in a section will be described based on the drawings. FIG. 6 is a sectional view showing the main part of the engine in the second embodiment, and FIG. 7 is a partial view of the outer front surface of the cowling.

The basic structure of the turbojet engine (hereinafter referred to as engine) of the second embodiment is composed of three parts, a compressor, a combustion chamber and a turbine, as in FIG. The air that has entered from the front of the engine 11 passes through the low-pressure compressor 13 inside the engine 11, and a part of the air is used as combustion air to be compressed in a series of compressors by a medium-pressure compressor 14 and then a high-pressure compressor 15 for combustion. Chamber 16
to go into. When fuel is injected into the combustion air in the combustion chamber 16, the fuel is burned at once and high temperature and high pressure combustion gas is generated. The high-temperature and high-pressure combustion gas turns the turbine to actuate the compressor as a driving force, and also violently ejects behind the engine 11 to become a propulsive force. As the turbine, a high pressure turbine 17, a medium pressure turbine 18, and a low pressure turbine 19 are installed in this order from the combustion chamber. On the other hand, other compressed air that has passed through the low-pressure compressor 13 in the engine 11 and is not introduced into the combustion chamber 16 is ejected as bypass air to the rear of the engine 11 and merges with the high-temperature and high-pressure combustion gas ejected from the low-pressure turbine 19 to form a jet together. It is ejected as the driving force of the engine. In a cowling 12 which houses an engine 11 which is a series of combustion equipments having these configurations, a spiral is provided on the outer front part of the cowling 12 in order to give a swirling flow to the air flowing along the outer periphery of the cowling 12. A swirl vane 35 is provided.

Next, the structure of the outer front surface portion of the cowling 12 which is a characteristic portion of the present invention will be described in detail. FIG. 7 is a partial view of the outer front surface portion of the cowling in FIG. 6, and FIGS. 8G, 8H, and 8J show one of the swirl vanes 35 provided on the outer wall of the outer front surface portion of the cowling 12. FIG. 3 is a diagram schematically showing one from the direction of arrow G and arrow H, or is a cross-sectional view of J taken along line JJ. 9 and 10 show cowling 1
2 is a cross-sectional view of the outer front surface portion of FIG.

As shown in FIG. 6, the outer front portion of the cowling 12 is formed in a circular cylindrical shape so as to cover the engine 11, and the upper portion is fixed to the main wing by the pylon 20. On the outer wall of the outer front part of the cowling 12,
A plurality of (six in the figure) swirl vanes 35 are provided at regular intervals. Each swirl vane 35 is bent in the swirling direction R along the outer wall portion of the outer front surface portion of the cowling 12 so that the air flowing through the outer wall of the outer front surface portion of the cowling 12 swirls in the R direction. It is provided.

As shown in FIGS. 8G to 8J, the swirl vane 35 is formed in a complicated twisted vane shape. The swirl vane 35 first has a height from the outer wall portion of the outer front surface portion of the cowling 12 to the protruding end portion 38, that is, the cowling 1.
It is formed so as to gradually increase from the tip position of No. 2 toward the rear part of the cowling 12. The height of the swirl blade 35 is set to a peak 36 before the swirl blade end point, and thereafter, the height of the swirl blade 35 is gradually reduced. The swirl vanes 35 are provided so that the twist angle α with respect to the axial direction of the cowling 12 is gradually increased, that is, from the tip position of the cowling 12 toward the rear part of the cowling 12.
Further, the swirl vane 35 is provided so that the position of the tip end portion 38 thereof is inclined from the radial direction of the cowling 12 along the swivel direction R by an inclination angle β so that the side surface portion 37 is inclined.

Next, the operation and effect of the outer front wall portion of the cowling 12 constructed as above will be described.

In a navigating aircraft, the air facing the outer outer wall of the cowling 12 housing the engine 11 is guided from the front of the cowling 12 to the rear. At this time, a part of the air flowing in the vicinity of the outer front wall of the cowling 12 hits the side surface portion 37 of the swirl vane 35 and flows along the side surface portion 37 of the swirl vane 35 provided in a spiral shape. As a result, a flow component in the circumferential direction R is given to the air, and the air gradually turns in the circumferential direction R. Then, the air that becomes a swirl flow and travels to the rear of the cowling 12 flows to the rear of the cowling 12 while maintaining the flow of the swirl flow and also giving the swirl flow to the surrounding air. Flow loss due to air resistance occurs around the outer outer wall of the cowling 12 that houses the engine 11 of a normal aircraft.
However, as in the present embodiment, if a swirl flow is given to the air around the cowling 12 in advance so that the air flows to the rear of the cowling 12, the loss due to such air resistance can be reduced to some extent.

In addition, the air flowing around the outer outer wall of the cowling 12 is hardly rectified. In particular, in the front portion of the cowling 12 where the air first confronts, a severe turbulent state is temporarily generated, and due to the airflow resistance due to this turbulent flow, various losses such as the flow velocity and pressure of the air flowing to the rear of the cowling 12 occur. However, it is considered that propulsive force is reduced. However, in the present embodiment, the action of the swirling vanes 35 that imparts a swirling flow imparts directionality to the flow, so that it is possible to eliminate a severe turbulent flow state or reduce the degree thereof.

Further, the swirl flow can be effectively generated by forming the swirl vane 35 on the outer wall of the outer front surface of the cowling 12 as described above.
That is, since the height of the swirl vane 35 gradually increases toward the rear of the cowling 12, and the twist angle α of the swirl vane 35 gradually increases toward the rear of the cowling 12, the swirl vane 35 increases. It is possible to generate the swirling flow by maximizing the size at the swirl vane end point while suppressing the influence of the flow velocity loss caused by 35 as much as possible.

Further, the swirl vane 35 is provided so as to be inclined by an inclination angle β, and the height of the swirl vane 35 is set to a peak 36 before the end point of the swirl vane, and thereafter the height of the swirl vane 35 is gradually lowered. By doing so, the gas flow in the vicinity of the outer wall portion on the outer front surface of the cowling 12 is directed outward from the cowling 12, so that the swirl vanes 35 do not directly act.
2 A swirling flow can be generated in the air around the periphery of the air. Further, the gas near the outer outer wall portion of the cowling 12 having a low flow velocity is guided to the air near the outer wall portion having a high flow velocity while suppressing the generation of turbulence, so that the flow of the entire fluid near the outer outer wall portion of the cowling 12 is reduced. It can be made smoother.

As described above, according to the outer wall structure of the outer front surface of the cowling 12 which houses the engine 11 of the second embodiment, the air acting on the outer wall of the cowling 12 in the vicinity of the outer wall of the cowling 12 is directly changed to air. By generating the swirling flow, various losses that occur at that time can be reduced, thereby maintaining the boundary layer of air around the outer wall of the cowling 12 in a laminar flow or improving the boundary layer separation. You can

The outer wall structure of the outer front surface of the cowling 12 which houses the engine 11 of the present invention is not limited to the above-described embodiment, and may be modified within the scope not departing from the contents described in the claims. It is possible. For example, the following configuration can be adopted.

The conditions such as the size and shape of the swirl vanes 35, the number of the swirl vanes 35 and the locations thereof can be changed as appropriate, and are optimal depending on the type of the cowling 12, the outer diameter of the outer side of the cowling 12, the swirling flow strength, and the like. May be designed so as to obtain the flow (swirling flow). For example, in FIG.
As shown in, the swirl vane 35 may be formed so that its cross section has a substantially triangular shape. In this case, since there is no half-closed space on the back side of the swirl vane 35, the gas that has flowed around to the back side of the swirl vane 35 stays there, and a state occurs that impedes the smooth flow of the entire gas. Can be avoided. Further, when the swirl vane 35 has such a shape, the strength of the swirl vane 35 itself and the mounting strength thereof are increased.
The outer wall can be integrally formed by a method such as casting.

[0053]

According to the first aspect of the present invention, the low pressure compression fan in the turbofan jet engine operates by giving a swirling flow to the combustion air or the air sucked and supplied into the turbofan jet engine. At this time, the combustion air or the air can be efficiently flowed and filled in the turbofan jet engine. As a result, it is possible to reduce various losses that occur when the combustion air or air flows into the turbofan jet engine when the low-pressure compression fan operates, and thus to reduce the load on the low-pressure compression fan and each compression fan. You can

According to the invention described in claim 2 or 3, in addition to the effect of the invention described in claim 1, the swirl flow is effectively generated near the low pressure compression fan while suppressing the loss of the flow velocity as much as possible. be able to.

According to the invention of claim 4, claim 1
In addition to the effect of the invention described in any one of 1 to 3, the swirling flow can be effectively generated even in the vicinity of the center of the suction port axis of the intake passage in the cowling where the swirling blade does not directly act. In addition, by guiding the gas with a slow flow velocity near the inner wall to the vicinity of the axial center with a faster flow velocity, the flow of combustion air or air flowing into the engine is made smooth and when the low-pressure compression fan operates. It can efficiently flow into the turbofan jet engine.

According to the invention of claim 5, claim 4
In addition to the effects of the invention described in (1), the strength of the swirl vane itself and the mounting strength thereof can be increased.

According to the sixth aspect of the invention, the turbulent flow in the air on the cowling surface is suppressed by giving a swirling flow to the air flowing to the outer wall of the outer front surface of the cowling housing the turbofan jet engine, and the turbulent flow in the air on the cowling surface is suppressed. The air on the cowling surface can be smoothly discharged rearward while maintaining the laminar flow of the airflow in the direction. As a result, various losses in the air flow on the outer wall surface of the cowling outer side can be reduced, and by extension, the load on the turbofan jet engine can be reduced, so that the propulsive force of the turbofan jet engine can be improved. .

According to the invention described in claims 7 to 9, in addition to the effect of the invention described in claim 6, in a place near the outer wall of the outer front surface of the cowling with which air comes into direct contact, while suppressing the loss of the flow velocity as much as possible. A swirling flow can be effectively generated.

According to the invention described in claim 10, in addition to the effect of the invention described in any one of claims 6 to 9, even in the air flowing around the outer peripheral outer wall of the cowling where the swirl vanes do not directly act. The swirling flow can be effectively generated. In addition, by guiding the gas having a low flow velocity near the outer outer wall of the cowling to the air near the periphery having a higher flow velocity, the air flowing through the outer outer wall of the cowling is smoothed to suppress the turbulent flow to the rear of the cowling,
Moreover, it is possible to efficiently flow in while maintaining a laminar flow.

According to the eleventh aspect of the invention, in addition to the effect of the tenth aspect of the invention, the strength of the swirl vane itself and its mounting strength can be increased.

[Brief description of drawings]

FIG. 1 is a sectional view showing a schematic configuration of a turbojet engine that is a first embodiment embodying the invention.

FIG. 2 is a partial perspective view showing a suction port portion of an intake passage of a turbojet engine according to a first embodiment of the present invention, taken along a line YY.

FIG. 3 is a view schematically showing one of the swirl vanes at the suction port of the intake passage of the turbojet engine from different directions, and (A) is a view showing from the direction of arrow A; , (B) is a view from the direction of arrow B, and (C) is a view from the direction of arrow C.

FIG. 4 is a partial cross-sectional view showing a suction port portion of an intake passage portion of the turbojet engine cut along a line YY.

FIG. 5 is a partial cross-sectional view showing a suction port portion of an intake passage portion of a turbojet engine, which is another embodiment embodying the present invention, in a broken manner similarly to FIG.

FIG. 6 is a cross-sectional view showing a schematic configuration of the external appearance of a turbojet engine that is a second embodiment of the present invention.

FIG. 7 is a partial perspective view showing a cowling front surface portion of a turbojet engine according to a second embodiment of the present invention, taken along line XX.

FIG. 8 is a view schematically showing one of the swirl vanes in the front portion of the cowling of the turbojet engine from different directions, and (G) is a view from the direction of arrow G; Is a diagram showing from the direction of arrow H,
(J) is a cross-sectional view taken along line JJ.

FIG. 9 is a partial cross-sectional view showing a cowling front surface portion of the turbojet engine taken along line XX.

FIG. 10 is a partial cross-sectional view showing a cowling front surface portion of a turbojet engine, which is another embodiment of the present invention, similarly to FIG.

[Explanation of symbols]

11 Turbojet Engine 12 Cowling 13 Low Pressure Compressor 14 Medium Pressure Compressor 15 High Pressure Compressor 16 Combustion Chamber 17 High Pressure Turbine 18 Medium Pressure Turbine 19 Low Pressure Turbine 20 Pylon 21 Suction Port (Intake Port) of Engine Intake Port 30 Inside Engine Of the swirl vane 31 at the suction port of the intake passage of the swirl vane side face 32 of the suction vane of the intake passage of the engine 32 swirl vane tip 35 at the suction port of the intake passage of the engine 35 on the outer wall of the cowling outer front face Swirl vane 36 Swirling vane peak point on outer wall of cowling outer front side 37 Swirling vane side face 38 on outer wall of cowling outer front face Swirling vane tip R on outer wall of cowling outer front face R Swirling direction F Direction of intake air in intake passage

Claims (11)

[Claims] 1. A plurality of compression turbofan facilities having different compression pressures for introducing outside air for generating propelling air into an engine or a combustion chamber, and driven by high-pressure combustion gas for driving the compression turbofan facilities. A turbofan jet provided with a plurality of drive turbine equipment, a series of combustion equipment including equipment for supplying fuel to a combustion chamber by a fuel supply means, and a combustion chamber equipment, and a cowling for accommodating the series of combustion equipment In the engine, the air sucked into the engine or the combustion chamber is introduced into the suction port portion on the front surface of the low-pressure compression fan in the turbofan jet engine to the inside in the radial direction of the suction port portion on the front surface of the low-pressure compression fan. The protruding swirl vanes
By providing spirally along the inner wall of the suction port on the front surface of the low-pressure compression fan, the air sucked into the low-pressure compression fan inside the engine is swirled and flows into the low-pressure compression fan inside the engine. A turbofan jet engine characterized by being configured to allow it. 2. The height to the tip of the swirl vane is gradually increased from a position far from the low pressure compression fan toward the low pressure compression fan. Turbofan jet engine. 3. The swirl vane is provided so that a twist angle of the swirl vane with respect to an axial direction of the suction port portion gradually increases from a position far from the low pressure compression fan toward the low pressure compression fan. The turbofan jet engine according to claim 1 or 2, characterized in that. 4. The swirl blade is provided so that a side surface portion of the swirl blade is inclined from a radial direction of the suction port portion toward a rotation direction side of a swirl flow. The turbofan jet engine according to any one of claims. 5. The cross-sectional shape of the swirl vane perpendicular to the axial direction of the suction port is formed so that it gradually widens from the projecting end of the swirl vane toward the inner wall of the suction port. The turbofan jet engine according to claim 4, wherein. 6. A plurality of compression turbofan facilities having different compression pressures for introducing outside air for generating propelling air into an engine or a combustion chamber, and driven by high pressure combustion gas for driving the compression turbofan facilities. A plurality of drive turbine equipment, a series of combustion equipment including equipment for supplying fuel to the combustion chamber by the fuel supply means and a combustion chamber equipment, and a cowling for accommodating an engine which is the series of combustion equipment. In the turbofan jet engine, on the outer front surface of the cowling, a swirl vane protruding radially outward of the cowling is provided in a spiral shape along the outer outer wall portion of the cowling, so that the outer outer wall portion of the cowling is formed. The air flowing along the engine is swirled and discharged to the rear of the engine. Is a turbofan jet engine. 7. The height from the front surface of the cowling to the rear of the cowling is gradually increased from the front surface of the cowling to the projecting end portion of the swirl blade installed on the outer wall portion of the cowling. The turbofan jet engine according to claim 6, which is characterized in that. 8. The height of the swirl vane installed on the outer wall portion outside the cowling to the tip end of the swirl vane is the maximum peak of the swirl vane before the end point of the swirl vane, and thereafter the swirl vane. The turbofan jet engine according to claim 6, wherein the height of the turbofan jet engine is gradually reduced. 9. The swirl vane is provided such that the twist angle of the swirl vane installed on the outer wall portion outside the cowling gradually increases from the front surface of the cowling toward the rear of the cowling. The turbofan jet engine according to any one of claims 6-8. 10. A side surface portion of the swirl vane installed on an outer wall portion outside the cowling is inclined from a radial direction of the cowling to a rotation direction side of a swirling flow,
The turbofan jet engine according to any one of claims 6 to 9, wherein the swirl vane is provided. 11. The cross-sectional shape of the swirl vane with respect to the swirl vane installed on the outer wall portion of the outer side of the cowling gradually becomes wider as it approaches the outer wall portion of the cowling from the projecting end portion of the swirl vane. The turbofan jet engine according to claim 10, wherein the turbofan jet engine is formed as described above.