Turbofan engine core cabin
By designing an intake and exhaust section within the core compartment of the turbofan engine, an initial vortex is formed and the airflow develops along an axial spiral, solving the problems of uneven cooling and poor heat exchange within the core compartment of the turbofan engine, thereby improving the overall cooling effect and reducing the temperature.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- COMMERCIAL AIRCRAFT CORP OF CHINA LTD
- Filing Date
- 2026-03-11
- Publication Date
- 2026-05-12
AI Technical Summary
The existing ventilation structure of the core compartment of turbofan engines has problems with uneven distribution of cooling airflow and poor heat exchange, which leads to overheating in some areas and poses a fire risk.
The intake section allows the bypass gas to flow into the core compartment radially inward and circumferentially on one side, and forms an initial vortex through the exhaust section. The cooling airflow develops stably in a spiral manner along the axial direction in the core compartment, achieving global cooling and heat exchange.
It significantly improved the uniformity of airflow distribution in the core compartment, reduced the temperature in the core compartment, reduced the overheated area, reduced the risk of fire, and improved heat exchange efficiency.
Smart Images
Figure CN122014419A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of ventilation and cooling of aircraft power plants, and more particularly to the core compartment of turbofan engines. Background Technology
[0002] When a turbofan engine in a civil aircraft is running, a large amount of heat accumulates in the core compartment. This heat rises the temperature inside the core compartment through heat exchange activities such as radiation and convection. Prolonged high temperatures inside the core compartment can easily cause the system accessories inside the core compartment to overheat, affecting reliability and even posing a fire risk. Therefore, ventilation of the turbofan engine core compartment is necessary.
[0003] Previously, the ventilation structure of the turbofan engine core compartment mainly included air inlets distributed on the upstream core compartment wall and exhaust ring gaps at the downstream core compartment end. The air inlets introduced cooling airflow through the outer bypass duct, and the cooling airflow exchanged heat in the core compartment and flowed out through the exhaust ring gaps under the action of pressure difference.
[0004] In such a ventilation structure, considering the flow loss of the outer bypass duct, too many air inlets cannot be arranged, which can easily lead to uneven circumferential cooling effect of the core compartment. On the other hand, the cooling mechanism inside the compartment relies entirely on the ram effect of the airflow. The local cooling effect is obvious near the air inlet, but as the airflow moves along the engine axis, the cooling effect downstream is greatly reduced. The cooling airflow cannot complete sufficient heat exchange with the core compartment wall and high-temperature accessories and will be discharged into the outer bypass duct wake, which undoubtedly results in the waste of some outer bypass duct bleed air.
[0005] In other words, in the past, there was an irreconcilable contradiction between improving the uniformity of airflow distribution in the core compartment and improving the ventilation and heat exchange effect in the compartment. Summary of the Invention
[0006] The present invention was made in view of the above-mentioned problems, and its purpose is to provide a turbofan engine core compartment that helps to improve the uniformity of airflow distribution in the core compartment and improve the heat exchange effect in the core compartment.
[0007] To achieve the above objectives, the present invention provides a turbofan engine core compartment, comprising: an air intake that allows gas from an outer bypass duct to flow into the core compartment in a radially inward and circumferentially sideways manner; and an exhaust section that allows gas inside the core compartment to flow out to the outside in a circumferentially sideways manner.
[0008] According to the turbofan engine core compartment of the present invention, the cooling airflow introduced from the outer bypass duct by the intake section can easily form an initial vortex in the core compartment, improving the uniformity of airflow distribution in the intake area. Furthermore, through the cooperation of the intake section and the exhaust section, the vortex formed by the cooling airflow introduced from the outer bypass duct into the core compartment can easily develop stably in a spiral manner along the axial direction of the core compartment. The interlayer heat exchange of the inner layer to the outer layer is achieved through interlayer heat exchange of the quasi-free vortex in the core compartment. The high-speed airflow of the outer layer carrying more energy is discharged to the outside under the suction of the exhaust section, which can easily achieve efficient cooling and heat exchange of the entire core compartment.
[0009] Furthermore, in one embodiment of the turbofan engine core compartment of the present invention, the air intake forms a tubular flow path for gas flow and opens radially inward and circumferentially on one side inside the core compartment.
[0010] According to the turbofan engine core compartment of the present invention, the air intake can be used to better guide the cooling airflow introduced from the outer bypass duct to form an initial vortex within the core compartment.
[0011] Furthermore, in one embodiment of the turbofan engine core compartment of the present invention, the core compartment includes an outer wall, and the air intake includes: an air inlet formed on the outer wall of the core compartment; and an air intake pipe extending radially inward from the air inlet toward the outer wall of the core compartment and forming the tubular flow path.
[0012] The turbofan engine core compartment of the present invention has a simple air intake structure, which helps to reduce manufacturing costs.
[0013] Furthermore, in one embodiment of the turbofan engine core compartment of the present invention, the air intake pipe is provided in multiple circumferential directions.
[0014] According to the turbofan engine core compartment of the present invention, it is easy to ensure that the cooling airflow introduced from the outer bypass duct forms an initial vortex throughout the core compartment, which significantly improves the uniformity of airflow distribution in the intake area.
[0015] Furthermore, in one embodiment of the turbofan engine core compartment of the present invention, the core compartment includes an outer wall and a core casing located radially inside the outer wall. The exhaust portion includes: an annular gap formed by the downstream end of the outer wall and the downstream end of the core casing; and a partition that divides the annular gap into multiple parts in the circumferential direction and causes the airflow to flow to one side in the circumferential direction.
[0016] According to the turbofan engine core compartment of the present invention, the airflow in the core compartment easily forms a spiral shape at the tail of the core compartment, thereby further ensuring that the vortex formed by the cooling airflow introduced into the core compartment from the outer bypass duct develops stably in a spiral manner along the axial direction of the core compartment.
[0017] Furthermore, in one embodiment of the turbofan engine core compartment of the present invention, the partition is a guide vane.
[0018] The turbofan engine core compartment according to the present invention has a simple structure of the partition, which helps to reduce manufacturing costs.
[0019] Furthermore, in one embodiment of the turbofan engine core compartment of the present invention, the guide vanes are provided in a plurality of circumferential directions.
[0020] According to the turbofan engine core compartment of the present invention, it is easier to ensure that the airflow in the core compartment forms a spiral shape at the tail of the core compartment. Attached Figure Description
[0021] Figure 1 This is a schematic front perspective view of the core compartment of a turbofan engine according to an embodiment of the present invention.
[0022] Figure 2 This is a perspective view schematically illustrating the core compartment of a turbofan engine according to an embodiment of the present invention.
[0023] Figure 3 This schematically illustrates the head of the turbofan engine core compartment in an embodiment of the present invention. Figure 2 A partial sectional perspective view of a three-dimensional object cut at point X on the plane.
[0024] Figure 4 yes Figure 3 The main view of the portion shown.
[0025] Figure 5 This is a partial perspective view of the tail section of the turbofan engine core compartment according to an embodiment of the present invention.
[0026] Figure 6 yes Figure 5 The main view of the portion shown.
[0027] Figure 7 This is a front view used to illustrate the airflow and heat exchange within the core compartment of a turbofan engine according to an embodiment of the present invention.
[0028] Figure 8 This is a partial cross-sectional perspective view used to illustrate the airflow conditions within the core compartment of a turbofan engine according to an embodiment of the present invention.
[0029] Figure 9 The temperature field distribution diagram was obtained by simulating the core compartment of the turbofan engine in the comparative example. Figure 10The temperature field distribution diagram is obtained by simulating the core compartment of the turbofan engine according to the embodiment of the present invention. (Based on actual engineering conditions, the comparative example and the embodiment of the present invention have the same inlet flow rate (1.0 kg / s), back pressure environment (98835 Pa), and core casing surface heat generation power (5100 W / m²). 2 )).
[0030] (Symbol Explanation)
[0031] 1. Turbofan engine core compartment
[0032] 10. Core Module External Vent
[0033] 20 core casings
[0034] JQ intake
[0035] JQ1 air intake
[0036] JQ2 intake pipe
[0037] PQ exhaust section
[0038] PQ1 Annular Slot
[0039] PQ2 partition Detailed Implementation
[0040] Below, in conjunction with Figures 1 to 10 The core compartment of the turbofan engine according to an embodiment of the present invention will be described.
[0041] (Structure of the turbofan engine core compartment)
[0042] like Figure 1 and Figure 2 As shown, the turbofan engine core compartment 1 includes: an air intake JQ that allows gas from the bypass duct to flow into the core compartment in a radially inward (i.e., radially inward) and circumferential (i.e. circumferential) direction (in the illustrated example, counterclockwise when viewed from the rear, i.e., downstream end, towards the head, i.e., upstream end, of the core compartment); and an exhaust PQ that allows gas inside the core compartment to flow out to the outside in a circumferential direction.
[0043] Here, as Figure 1As shown, the turbofan engine core compartment includes: a core compartment outer wall 10; and a core casing 20 located radially inward of the core compartment outer wall 10. The core compartment outer wall 10 and the core casing 20 are both cylindrical. The core compartment interior is formed between the core compartment outer wall 10 and the core casing 20. Specifically, the core compartment outer wall 10 includes an upstream section, a midstream section, and a downstream section arranged sequentially along the axial direction (i.e., the core compartment's axial direction). The upstream section is a cylindrical shape with a fixed diameter along the axial direction. The midstream section extends downstream from the downstream end of the upstream section and is a cylindrical shape with a diameter increasing towards the downstream side. The downstream section extends downstream from the downstream end of the midstream section and is a cylindrical shape with a diameter decreasing towards the downstream side. The core casing 20 includes an upstream section, a midstream section, and a downstream section arranged sequentially along the axial direction. The upstream section is a cylindrical shape with a diameter decreasing towards the downstream side. The upstream section of the casing includes a first section and a second section. The first section extends downstream from the downstream end of the upstream section of the casing and is cylindrical with a fixed diameter in the axial direction. The second section extends downstream from the downstream end of the first section and is cylindrical with a diameter that increases towards the downstream side. The downstream section of the casing extends downstream from the downstream end of the upstream section of the casing and is cylindrical with a fixed diameter in the axial direction. The connection between the upstream section and the upstream section of the casing is upstream of the upstream section of the outer wall and the midstream section of the outer wall. The connection between the upstream section and the midstream section of the outer wall is upstream of the upstream section of the outer wall and the first section of the outer wall and the second section of the outer wall. The connection between the upstream section and the downstream section of the casing is upstream of the downstream section of the casing and the midstream section of the outer wall.
[0044] In addition, such as Figure 3 and Figure 4 As shown, the air intake JQ forms a tubular flow path for gas flow and opens radially inward and circumferentially on one side inside the core compartment. Specifically, the air intake JQ includes: an air inlet JQ1, which is located on the outer wall 10 of the core compartment; and an air intake pipe JQ2, which extends radially inward from the air inlet toward the outer wall 10 of the core compartment and forms a tubular flow path. The centerline of the air intake pipe JQ2 does not coincide with the radial direction of the core compartment, but is deflected tangentially toward the core compartment. Furthermore, multiple air intake pipes JQ2 are provided circumferentially. More specifically, multiple air intake pipes JQ2 extend radially inward from the periphery of the air inlet JQ1 toward the outer wall 10 of the core compartment along a straight line inclined relative to the circumferential direction, and are provided at equal intervals circumferentially.
[0045] In addition, such as Figure 5 and Figure 6As shown, the exhaust section PQ includes: an annular slit PQ1, which is surrounded by the downstream end of the core compartment outer wall 10 and the downstream end of the core casing 20; and a partition PQ2, which divides the annular slit PQ1 into multiple parts in the circumferential direction and causes the airflow to flow towards one side in the circumferential direction. Specifically, the partition PQ2 is a guide vane. Furthermore, multiple guide vanes are arranged in the circumferential direction. More specifically, the downstream ends of the core compartment outer wall 10 and the core casing 20 are flush. The radially outer side of the guide vane is attached to the core compartment outer wall 10, and the radially inner side of the guide vane is attached to the core casing 20. The guide vane is inclined relative to the axial direction in a manner that the closer it is to the downstream side, the closer it is to the circumferential side. Multiple guide vanes are arranged at equal intervals in the circumferential direction to form a grid shape. In the circumferential direction, the number of guide vanes is greater than the number of intake pipes. Furthermore, the ends of the annular slit PQ1 and the guide vanes are flush.
[0046] (Airflow within the core compartment of a turbofan engine)
[0047] From the perspective of a single cross-section, such as Figure 7 As shown, the cooling airflow introduced through the outer bypass duct enters the core compartment in an approximately tangential direction, forming an initial vortex. The airflow inside the vortex is heated and expands by the core casing 20, resulting in a significant increase in velocity and angular velocity (angular velocity ω1 of the inner airflow > angular velocity ω2 of the outer airflow). Due to the different angular velocities between different levels distributed radially within the vortex, the inner airflow transfers energy to the outer airflow with lower angular velocity through gas viscous friction. The inner part of the airflow loses energy, its velocity decreases, and its temperature decreases, continuing the heat exchange process under the influence of the temperature gradient within the core casing 20.
[0048] From the axial perspective of the core module, such as Figure 8 As shown, under the combined effect of upstream pressure and downstream suction in the core module, the cooling airflow flows downstream in a spiral shape, causing interlayer frictional heat transfer to continue to develop along the axial direction. The airflow in the outer part of the core module continuously gains momentum and increases kinetic energy as it moves downstream, and finally escapes through the guide vanes.
[0049] (Simulation of temperature field distribution inside the core compartment of a turbofan engine)
[0050] Using CFD techniques, ventilation configuration simulations were performed on the core compartment of the turbofan engine in the comparative example (where the extension direction of the centerline of the intake pipe coincides with the radial direction of the core compartment, and the exhaust section does not include the partition) and the core compartment of the turbofan engine in the embodiment of the present invention.
[0051] Under the same ventilation intake and core casing heat generation conditions, the internal temperature fields of the turbofan engine core compartment in the comparative example and the turbofan engine core compartment in the embodiment of the present invention are respectively as follows: Figure 9 and Figure 10As shown, it can be seen that the turbofan engine core compartment of the present invention significantly reduces the overall temperature inside the core compartment, with the average temperature of the core casing wall reduced by about 4.7K and the peak wall temperature reduced by about 23.9K. At the same time, it eliminates the local overheated area of the wall in the configuration of the comparative example, which also means a reduction in the risk of fire.
[0052] (Main technical effects of this embodiment)
[0053] According to the turbofan engine core compartment 1 of this embodiment, under the combined action of the upstream and downstream ventilation structures, the cooling airflow evolves in a spiral form within the core compartment, continuously exchanging heat through interlayer viscous friction. This flow mechanism not only increases the residence time of the cooling airflow within the compartment, but more importantly, it fundamentally solves the problem in the prior art where the cooling airflow fails to complete sufficient heat exchange with the core compartment walls and high-temperature accessories before being discharged into the outer bypass wake. This achieves a highly efficient cooling and heat exchange process for the entire core compartment, while having a relatively small impact on the aerodynamic performance of the outer bypass duct, and is expected to further reduce the bleed air volume of the outer bypass duct and reduce cruise losses.
[0054] The present invention has been described above by way of example with reference to the accompanying drawings. Obviously, the specific implementation of the present invention is not limited to the above embodiments.
[0055] For example, in the above embodiment, the angle of the intake pipe JQ2 relative to the radial direction can be set appropriately as needed.
[0056] Furthermore, in the above embodiment, the intake pipe JQ2 is formed in a straight line shape, but it is not limited to this; the intake pipe JQ2 may also be formed in an arc shape.
[0057] Furthermore, in the above embodiments, the position and number of intake pipes JQ2 in the circumferential direction can be appropriately set as needed.
[0058] Furthermore, in the above embodiment, the air intake JQ includes an air intake pipe JQ2 to form a tubular flow path, but it is not limited to this. An annular member that is in close contact with the inner wall of the outer wall 10 of the core compartment may also be provided in the core compartment, and a through hole that is inclined relative to the radial direction is opened on the annular member to form a tubular flow path.
[0059] Furthermore, in the above embodiments, the position and number of the partition PQ2 in the circumferential direction can be appropriately set as needed.
[0060] Furthermore, in the above embodiment, the ends of the annular slit PQ1 and the guide vane are flush, but it is not limited to this; the ends of the annular slit PQ1 and the guide vane may also be offset axially.
[0061] Furthermore, in the above embodiment, the partition PQ2 is formed by a guide vane, but it is not limited to this. It is also possible to provide an annular member that is in close contact with the outer wall 10 of the core compartment and the core casing 20 respectively, and to open through holes that are inclined relative to the radial direction on the annular member.
[0062] Furthermore, in the above embodiments, when viewed from the tail of the core module toward the head of the core module, the circumferential side is the counterclockwise side, but it is not limited to this. When viewed from the tail of the core module toward the head of the core module, the circumferential side can also be the clockwise side.
[0063] It should be understood that within the scope of this invention, the various parts of the embodiments can be freely combined, or the various parts of the embodiments can be appropriately modified or omitted.
Claims
1. A turbofan engine core compartment, characterized in that, include: The air intake allows the gas from the outer bypass duct to flow into the core compartment in a radially inward and circumferentially sideways manner. as well as The exhaust system allows gases inside the core compartment to flow out to the outside in a circumferential direction.
2. The turbofan engine core compartment according to claim 1, characterized in that, The air intake forms a tubular flow path for gas flow and opens radially inward and circumferentially to one side inside the core compartment.
3. The turbofan engine core compartment according to claim 2, characterized in that, Including the outer wall of the core module, The air intake section includes: An air intake, which is located on the outer wall of the core compartment; and An air intake pipe extends radially inward from the air inlet toward the outer wall of the core compartment and forms the tubular flow path.
4. The turbofan engine core compartment according to claim 3, characterized in that, The air intake pipe has multiple sections arranged in the circumferential direction.
5. The turbofan engine core compartment according to any one of claims 1 to 4, characterized in that, This includes the outer wall of the core compartment and the core casing located radially inside the outer wall of the core compartment. The exhaust section includes: An annular gap, formed by the downstream end of the outer wall of the core compartment and the downstream end of the core casing; and The partition divides the annular gap into multiple parts in the circumferential direction and causes the airflow to flow in the circumferential direction.
6. The turbofan engine core compartment according to claim 5, characterized in that, The partition is a flow guide plate.
7. The turbofan engine core compartment according to claim 6, characterized in that, The guide vanes are arranged in multiple circumferential directions.