Reverse thrust volute and reverse thrust volute design method
By optimizing the size ratio of the inlet, turning and outlet sections of the reverse push volute, a reverse push volute that is easy to move is designed, which solves the problem of diversion difficulties caused by excessive size and weight of the reverse push volute in the prior art, and achieves the improvement of the air flow diversion effect and test efficiency.
Patent Information
- Application Number
- CN202410001812.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-01-02
- Publication Date
- 2025-07-11
AI Technical Summary
The existing reverse push volute is too large in size and weight and is not easy to move, which makes it difficult to effectively divert the back push airflow during engine tests and prevent the airflow from being sucked into the engine, affecting the test results.
A reverse push volute shell is designed, including the inlet section, turning section and outlet section. By optimizing the dimensional proportion and structural parameters of each section, it is easy to move, and effectively directs the reverse push airflow to reduce the impact of the airflow on the engine.
It realizes convenient movement and effective flow diversion of the reverse push volute shell, reduces the total pressure difference and leakage of the airflow to the engine, meets the test requirements, shortens the test cycle and reduces the mechanical power requirements.
Smart Images
Figure CN120293527A_ABST
Abstract
Description
Technical Field
[0001] The present disclosure relates to the field of engine overall tests, and particularly to a reverse thrust volute and a design method thereof. Background Art
[0002] During the development of a cascade type reverse thrust device, it is necessary to verify its function on an indoor test bench. During the verification process, if there is no other device to guide the reverse thrust airflow, since the reverse thrust device that opens the engine bypass airflow folds back, the folded-back airflow will flow upstream towards the test workshop and will be inhaled by the engine intake port, resulting in abnormal operation of the engine. Therefore, generally when conducting a reverse thrust function verification test on an indoor test bench, a reverse thrust airflow re-inhalation prevention device (also known as: reverse thrust volute) is installed on the radially outer side of the reverse thrust exhaust to guide the airflow discharged forward by the reverse thrust device backward so that the airflow can be smoothly discharged into the ejector cylinder of the test workshop.
[0003] When conducting an indoor bench reverse thrust function test, it is necessary to cover the reverse thrust volute on both sides of the reverse thrust exhaust port before the test. When inspecting the engine, it is necessary to move the reverse thrust volute away. Currently, the size and weight of the reverse thrust volute in the related art are too large and it is not easy to move. Summary of the Invention
[0004] In view of this, the embodiments of the present disclosure provide a reverse thrust volute and a design method thereof, making the reverse thrust volute easy to move.
[0005] In one aspect of the present disclosure, a reverse thrust volute for an engine reverse thrust test is provided, including:
[0006] An inlet section for absorbing the reverse thrust airflow from the engine;
[0007] An outlet section for discharging the reverse thrust airflow towards the ejector cylinder of the test bench; and
[0008] A turning section located between the inlet section and the outlet section for guiding the reverse thrust airflow to flow from the inlet section to the outlet section;
[0009] Wherein, the width of the inlet section along the engine axis direction is H1, and the axial width at the outlet of the engine cascade is H out , and the width H1 of the inlet section is 1.9437 - 2.1483 times the width H out at the cascade outlet.
[0010] In some embodiments, the width H1 of the inlet section along the engine axis direction is 2.046 times the axial width H out at the cascade outlet.
[0011] In some embodiments, the width of the turning section along the engine axis is H2, and the width H2 of the turning section is 0.5282 to 0.5838 times the width H1 of the inlet section.
[0012] In some embodiments, the width H2 of the turning section along the engine axis is 0.556 times the width H1 of the inlet section.
[0013] In some embodiments, the distance L2 between the turning section and the inlet section along the engine radial direction is 0.7695 to 0.8505 times the width H1 of the inlet section.
[0014] In some embodiments, the distance L2 between the turning section and the inlet section along the engine radial direction is 0.81 times the width H1 of the inlet section.
[0015] In some embodiments, the distance L1 between the midpoint of the inlet section and the midpoint of the cascade outlet along the reverse thrust airflow direction is L1, and the maximum takeoff flow rate of the engine is W max , the distance L1 between the midpoint of the inlet section and the midpoint of the cascade outlet along the reverse thrust airflow direction at the cascade outlet is 0.2579 to 0.2851 times the maximum takeoff flow rate W of the engine max times.
[0016] In some embodiments, the distance L1 between the midpoint of the inlet section and the midpoint of the cascade outlet along the reverse thrust airflow direction is 0.2715 times the maximum takeoff flow rate W of the engine max times.
[0017] In some embodiments, the inner curve radius of the turning section is R1, and the inner curve radius R1 of the turning section is 0.45 times the width H1 of the inlet section.
[0018] In some embodiments, the inner curve radius of the turning section is R1, the outer curve radius of the turning section is R2, the inner curve radius R1 of the turning section is 0.45 times the width H1 of the inlet section, and the outer curve radius R2 of the turning section is the sum of the inner curve radius R1 of the turning section and the width H2 of the turning section.
[0019] In some embodiments, a plurality of guide vanes are arranged at intervals along the direction perpendicular to the extension direction of the outlet section inside the outlet section, the number of the guide vanes is n, and the thickness of the guide vane is δ,
[0020] wherein,
[0021] In some embodiments, the thickness δ of the guide vane is 10 to 40 millimeters.
[0022] In some embodiments, the included angle between the extension direction of the outside of the inlet section and the extension direction of the outside of the turning section at the connection between the inlet section and the turning section is The included angle between the flow direction of the reverse thrust airflow at the outlet of the cascade and the radial direction of the cascade is The included angle between the extension direction of the outer side of the inlet section and the outer side of the turning section is the included angle between the reverse thrust airflow and the radial direction of the cascade 0.2 times of
[0023] In some embodiments, the included angle between the extension direction of the inner side of the outlet section and the engine axis direction is 16.5°.
[0024] In some embodiments, the included angle between the guide vane and the engine axis direction is 16.5°.
[0025] In some embodiments, the included angle between the normal line of the outlet section cross-section and the engine axis direction is 15°.
[0026] In some embodiments, the length of the outer side of the outlet section along the extension direction of the outlet section is L3, and the value of L3 ranges from 350 to 500 millimeters.
[0027] On the other hand of the embodiments of the present disclosure, a reverse thrust volute design method based on any of the above reverse thrust volutes is provided, including:
[0028] Obtain the axial width H at the outlet of the cascade out ;
[0029] According to the axial width H at the outlet of the cascade out and the second design factor K2, determine the width H1 of the inlet section along the engine axis direction;
[0030] wherein, H1 = K2 * H out , and the value of the second design factor K2 ranges from 1.9437 to 2.1483.
[0031] In some embodiments, the value of the second design factor K2 is 2.046.
[0032] In some embodiments, the reverse thrust volute design method further includes:
[0033] According to the width H1 of the inlet section along the engine axis direction and the third design factor K3, determine the width H2 of the turning section along the engine axis direction;
[0034] wherein, H2 = K3 * H1, and the value of the third design factor K3 ranges from 0.5282 to 0.5838.
[0035] In some embodiments, the value of the third design factor K3 is 0.556.
[0036] In some embodiments, the reverse thrust volute design method further includes:
[0037] Determine the distance L2 along the engine radial direction between the turning section and the inlet section according to the width H1 of the inlet section along the engine axis direction and the fourth design factor K4;
[0038] Wherein, L2 = K4 * H1, and the value of the fourth design factor K4 is 0.7695 - 0.8505.
[0039] In some embodiments, the value of the fourth design factor K4 is 0.81.
[0040] In some embodiments, the reverse thrust volute design method further includes:
[0041] Determine the distance L1 between the midpoint of the inlet section and the midpoint at the outlet of the cascade along the flow direction of the reverse thrust airflow according to the maximum takeoff flow rate W of the engine max and the first design factor K1;
[0042] Wherein, L1 = K1 * W max , and the value of the first design factor K1 is 0.2579 - 0.2851.
[0043] In some embodiments, the value of the first design factor K1 is 0.2715.
[0044] Therefore, according to the embodiments of the present disclosure, by setting the width H1 of the inlet section of the reverse thrust volute to 1.9437 - 2.1483 times the axial width at the outlet of the cascade of the engine, it helps to reduce the space profile occupied by the reverse thrust volute, reduce the weight of the housing, and avoid blocking the airflow from affecting the total pressure of the engine or causing leakage. While reducing the axial dimension of the reverse thrust volute, the total pressure difference and airflow leakage amount of the reverse thrust volute for the engine can still meet the test requirements, facilitating the movement of the reverse thrust volute by the staff during the experiment. BRIEF DESCRIPTION OF THE DRAWINGS
[0045] The drawings forming a part of the specification depict embodiments of the present disclosure and, together with the specification, are used to explain the principles of the present disclosure.
[0046] Referring to the drawings, the present disclosure can be more clearly understood according to the following detailed description, wherein:
[0047] Figure 1 (a) is a schematic plan view of some embodiments of a reverse thrust volute according to the related art;
[0048] Figure 1 (b) is a schematic plan view of some embodiments of a reverse thrust volute according to the present disclosure;
[0049] Figure 2A is a schematic structural view of some embodiments of a reverse thrust volute according to the present disclosure;
[0050] Figure 2B is a side view of some embodiments of the reverse-flow volute according to the present disclosure;
[0051] Figure 2C is a side view of some other embodiments of the reverse-flow volute according to the present disclosure;
[0052] Figure 2D is a schematic structural view of some other embodiments of the reverse-flow volute according to the present disclosure;
[0053] Figure 3 is a schematic plan view of some other embodiments of the reverse-flow volute according to the present disclosure;
[0054] Figure 4 is a schematic plan view of the inlet section of some embodiments of the reverse-flow volute according to the present disclosure;
[0055] Figure 5 is a schematic plan view of the turning section and the outlet section of some embodiments of the reverse-flow volute according to the present disclosure;
[0056] Figure 6 is a flowchart of some embodiments of the design method of the reverse-flow volute according to the present disclosure.
[0057] In the figure:
[0058] 10, engine; 11, cascade; 20, reverse-flow volute; 21, inlet section; 22, turning section; 23, outlet section.
[0059] It should be understood that the dimensions of the various parts shown in the drawings are not drawn in actual proportional relationship. In addition, the same or similar reference numerals represent the same or similar components. Detailed Embodiments
[0060] Now, various exemplary embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. The description of the exemplary embodiments is merely illustrative and in no way limits the present disclosure and its application or use. The present disclosure can be implemented in many different forms and is not limited to the embodiments described herein. These embodiments are provided to make the present disclosure thorough and complete, and to fully convey the scope of the present disclosure to those skilled in the art. It should be noted that: unless otherwise specifically stated, the relative arrangements of the components and steps, the components of the materials, the numerical expressions and the numerical values set forth in these embodiments should be construed as merely exemplary and not as limitations.
[0061] As used in this disclosure, terms such as "first", "second" and similar words do not denote any order, quantity or importance, but are only used to distinguish different parts. Words such as "including" or "comprising" mean that the elements before this word cover the elements listed after this word, and do not exclude the possibility of also covering other elements. Terms such as "upper", "lower", "left" and "right" are only used to represent relative positional relationships. When the absolute position of the object being described changes, the relative positional relationship may also change accordingly.
[0062] In this disclosure, when it is described that a specific device is located between a first device and a second device, there may or may not be an intermediate device between the specific device and the first device or the second device. When it is described that a specific device is connected to other devices, the specific device may be directly connected to the other devices without an intermediate device, or may not be directly connected to the other devices but have an intermediate device.
[0063] All terms used in this disclosure (including technical terms or scientific terms) have the same meaning as understood by those of ordinary skill in the art to which this disclosure pertains, unless otherwise specifically defined. It should also be understood that terms defined in a general dictionary, for example, should be interpreted as having a meaning consistent with their meaning in the context of the relevant art, and should not be interpreted in an idealized or overly formal sense, unless specifically defined as such here.
[0064] Technologies, methods and devices known to those of ordinary skill in the relevant field may not be discussed in detail, but where appropriate, the said technologies, methods and devices should be regarded as part of the specification.
[0065] When conducting a full - scale aerodynamic test of the cascade reverse - thrust device of a turbofan engine with a cascade reverse - thrust device on an indoor test bench, it is necessary to set up a reverse - thrust volute to collect and divert the reverse - thrust airflow when the engine is in the reverse - thrust condition, so as to guide and discharge the airflow discharged forward from the reverse - thrust device to the ejector barrel of the test bench.
[0066] The reverse - thrust volute is used to support the verification test of the reverse - thrust device of a high - bypass - ratio turbofan engine. The reverse - thrust device is a device that obtains reverse thrust by reversing the direction of the engine exhaust. There are various forms of reverse - thrust devices, such as: cascade reverse - thrust devices, baffle - type reverse - thrust devices, clamshell - type reverse - thrust devices, etc. Among them, the cascade reverse - thrust device is widely used in high - bypass - ratio turbofan engines.
[0067] Figure 1 (a) is a schematic plan view of some embodiments of a reverse - thrust volute according to the related art. Refer to Figure 1In (a), when conducting an indoor bench reverse thrust function test, it is necessary to cover the reverse thrust volute on both sides of the reverse thrust exhaust port before the test. When inspecting the engine, it is necessary to move the reverse thrust volute. In the related technology, the size and weight of the reverse thrust volute are too large and it is not easy to move.
[0068] In view of this, in one aspect of the embodiments of the present disclosure, a reverse thrust volute and a design method for the reverse thrust volute are provided to facilitate the movement of the reverse thrust volute. Figure 1 (b) is a schematic plan view of some embodiments of the reverse thrust volute according to the present disclosure. Figure 2A is a schematic structural view of some embodiments of the reverse thrust volute according to the present disclosure. Figure 2B is a side view of some embodiments of the reverse thrust volute according to the present disclosure. Figure 2C is a side view of some other embodiments of the reverse thrust volute according to the present disclosure. Figure 2D is a schematic structural view of some other embodiments of the reverse thrust volute according to the present disclosure. Figure 3 is a schematic plan view of some other embodiments of the reverse thrust volute according to the present disclosure. Figure 3 The A direction in is the axial direction of the engine. Figure 3 The B direction in is the radial direction of the engine. Figure 3 The C direction in is the flow direction of the reverse thrust air flow in the inlet section of the reverse thrust volute. Refer to Figure 1 (b) to Figure 3 In one aspect of the embodiments of the present disclosure, a reverse thrust volute is provided for the reverse thrust test of the engine 10.
[0069] The reverse thrust volute 20 includes: an inlet section 21, a turning section 22, and an outlet section 23. The reverse thrust volute is configured to absorb the reverse thrust air flow from the engine 10 through the inlet section 21, eject the reverse thrust air flow to the test bench ejector cylinder through the turning section 22. The turning section 22 is connected between the inlet section 21 and the outlet section 23 for guiding the reverse thrust air flow in the inlet section 21 to the outlet section 23. The circumferential notch of the reverse thrust volute is used for the arrangement of the adapter frame of the engine to avoid interference with the adapter frame.
[0070] The width of the port on the side of the inlet section 21 close to the engine along the B direction in the axial direction of the engine 10 is H1, that is, the width H1 at the start of the inlet section 21. The axial width at the outlet of the cascade 11 of the engine 10 is H out , and the width H1 of the inlet section 21 is out 1.9437 to 2.1483 times the width H at the outlet of the cascade 11.
[0071] In this embodiment, by setting the width H1 of the inlet section 21 of the reverse thrust volute to 1.9437 to 2.1483 times the axial width at the outlet of the cascade 11 of the engine 10, it helps to reduce the spatial profile occupied by the reverse thrust volute, reduce the weight of the housing, and avoid choking the air flow and affecting the total pressure of the engine or causing leakage. While reducing the axial dimension of the reverse thrust volute, the total pressure difference and air flow leakage of the reverse thrust volute to the engine can still meet the test requirements, facilitating the movement of the reverse thrust volute by the staff during the experiment.
[0072] Reference Figure 1 of (b) to Figure 3 , in some embodiments, the width H1 of the inlet section 21 in the axial direction of the engine 10 axis is 2.046 times the axial width H out at the outlet of the cascade 11. In this embodiment, the width H1 of the inlet section 21 in the axial direction of the engine 10 axis is preferably 2.046 times the axial width H out at the outlet of the cascade 11. On the premise of meeting the performance requirements such as the total pressure difference and air flow leakage of the turbine volute to the engine, it can also reduce the size and weight of the reverse thrust volute, facilitating the reduction of the mechanical power required to move the reverse thrust volute during the commissioning of the volute and the engine and the inspection of the engine during the test, and shortening the test cycle occupied by the removal and reinstallation of the reverse thrust volute.
[0073] Figure 4 is a schematic plan view of the inlet section of some embodiments of the reverse thrust volute according to the present disclosure. Reference Figure 1 of (b) to Figure 4 , in some embodiments, the width of the port of the turning section 22 close to the engine side in the B direction in the axial direction of the engine 10 axis is H2, that is, the width H2 at the start of the turning section 22. The width H2 of the turning section 22 is 0.5282 to 0.5838 times the width H1 of the inlet section 21.
[0074] In this embodiment, by setting the width H2 at the start of the turning section 22 to 0.5282 to 0.5838 times the width H1 at the start of the inlet section 21, the starting size of the turning section of the reverse thrust volute can be reduced, and choking the air flow and affecting the total pressure of the engine or causing leakage can be avoided. On the premise that the impact of the air flow on the reverse thrust volute is not too large and the pressure distribution and force conditions on the inner surface of the reverse thrust volute meet the test requirements, the reverse thrust volute is more convenient to move during the commissioning of the volute and the engine and the inspection of the engine during the test.
[0075] Reference Figure 1 of (b) to Figure 4, in some embodiments, the width H2 of the turning section 22 in the axial direction of the engine 10 is 0.556 times the width H1 of the inlet section 21. In this embodiment, the width H2 of the turning section 22 in the axial direction of the engine 10 is preferably 0.556 times the width H1 of the inlet section 21, so as to meet the impact condition of the air flow on the inner surface of the reverse thrust volute while reducing the contour size and weight of the volute.
[0076] Reference Figure 1 of (b) - Figure 4 , in some embodiments, the distance L2 in the radial direction of the engine 10 between the starting end of the turning section 22 and the starting end of the inlet section 21 is L2, and the distance L2 between the turning section 22 and the inlet section 21 is 0.7695 - 0.8505 times the width H1 of the inlet section 21.
[0077] In this embodiment, by setting the distance L2 between the turning section 22 and the inlet section 21 to be 0.7695 - 0.8505 times the width H1 of the inlet section 21, the radial size of the reverse thrust volute can be reduced, and under the limited entrainment effect, the turning section 22 can be prevented from being overly impacted or the air flow cannot be smoothly discharged from the turning section 22. While meeting the preset requirements for the total pressure loss of the reverse thrust volute, the radial size between the turning section 22 and the inlet section 21 and the engine is reduced, which is beneficial to reducing the radial size and weight of the reverse thrust volute.
[0078] Reference Figure 1 of (b) - Figure 4 , in some embodiments, the distance L2 in the radial direction of the engine 10 between the turning section 22 and the inlet section 21 is 0.81 times the width H1 of the inlet section 21. In this embodiment, the distance L2 in the radial direction of the engine 10 between the turning section 22 and the inlet section 21 is preferably 0.81 times the width H1 of the inlet section 21, thereby further reducing the radial size and weight of the reverse thrust volute, saving the mechanical power required to move the reverse thrust volute, and shortening the time occupied by the disassembly and assembly of the reverse thrust volute during the test.
[0079] Reference Figure 1 of (b) - Figure 4 , in some embodiments, the distance L1 in the flow direction of the reverse thrust air flow between the midpoint of the starting end of the inlet section 21 and the midpoint of the outlet of the cascade 11 is L1, and the maximum takeoff flow rate of the engine 10 is W max , the distance L1 in the flow direction of the reverse thrust air flow at the outlet of the cascade 11 between the midpoint of the inlet section 21 and the midpoint of the outlet of the cascade 11 is 0.2579 - 0.2851 times the maximum takeoff flow rate W of the engine 10 max times.
[0080] In this embodiment, by setting the distance L1 in the flow direction of the reverse thrust air flow at the outlet of the cascade 11 between the midpoint of the inlet section 21 and the midpoint of the outlet of the cascade 11 to be the maximum takeoff flow rate W of the engine 10max 0.2579 to 0.2851 times, on the premise that the total pressure difference and air flow leakage of the reverse thrust volute to the engine meet the preset requirements, the distance between the inlet of the reverse thrust volute and the reverse thrust outlet of the engine 10 is reduced, and the profile size occupied by the reverse thrust volute is reduced.
[0081] Reference Figure 1 of (b) to Figure 4 , in some embodiments, the distance L1 between the midpoint of the inlet section 21 and the midpoint at the outlet of the cascade 11 along the flow direction of the reverse thrust air flow is 0.2715 times the maximum takeoff flow rate W of the engine 10 max 0.2715 times.
[0082] Figure 5 is a schematic plan view of the turning section and the outlet section of the reverse thrust volute according to some embodiments of the present disclosure, referring to (b) to Figure 5 , in some embodiments, the inner curve radius of the turning section 22 is R1, and the inner curve radius R1 of the turning section 22 is 0.45 times the width H1 of the inlet section 21.
[0083] In this embodiment, the inner curve radius R1 of the turning section 22 can be selected as the recommended value of the reverse thrust volute used in a 15-ton large bypass ratio turbofan aeroengine, which can not only reduce the profile size of the turning section 22, but also prevent the impact load of the air flow on the curved section of the volute from being too large, meeting the test requirements.
[0084] Referring to (b) to Figure 5 , in some embodiments, the inner curve radius of the turning section 22 is R1, the outer curve radius of the turning section 22 is R2, the inner curve radius R1 of the turning section 22 is 0.45 times the width H1 of the inlet section 21, and the outer curve radius R2 of the turning section 22 is the sum of the inner curve radius R1 of the turning section 22 and the width H2 of the turning section 22.
[0085] In this embodiment, the outer curve radius R2 of the turning section 22 can be selected as the recommended value of the reverse thrust volute used in a 15-ton large bypass ratio turbofan aeroengine, which can not only reduce the profile size of the turning section 22, but also prevent the impact load of the air flow on the curved section of the volute from being too large, meeting the test requirements.
[0086] Referring to (b) to Figure 5 , in some embodiments, a plurality of guide vanes 231 are arranged at intervals inside the outlet section 23 in a direction perpendicular to the extending direction of the outlet section 23, the number of the guide vanes 231 is n, and the thickness of the guide vanes 231 is δ,
[0087] In this embodiment, by making the number of the vanes meet The exhaust angle of the airflow at the exhaust port of the reverse thrust volute is effectively controlled to reduce the weight of the reverse thrust volute while preventing the airflow discharged from the reverse thrust volute from being re-inhaled or entrained by the high-temperature airflow discharged from the engine.
[0088] Refer to (b) in 1. Figure 5 In some embodiments, the thickness δ of the guide vane 231 is 10 to 40 mm. In this embodiment, the thickness δ of the guide vane 231 can be selected as the recommended value of the reverse thrust volute used in a 15-ton high bypass ratio turbofan aircraft engine. On the premise of meeting the test performance requirements, the outline size and weight of the reverse thrust volute are further reduced, the mechanical power required to move the reverse thrust volute is saved, and the time taken for disassembly and assembly of the reverse thrust volute during the test is shortened.
[0089] Refer to (b) in 1. Figure 5 In some embodiments, the angle between the extension direction of the outer side of the entrance section 21 and the extension direction of the outer side of the turning section 22 at the junction of the entrance section 21 and the turning section 22 is The angle between the flow direction of the reverse thrust airflow at the outlet of the cascade 11 and the radial direction of the cascade 11 is The angle between the outer extension direction of the entrance section 21 and the outer side of the turning section 22 is the angle between the thrust reverser airflow in the inlet section 21 and the radial direction of the blade cascade 11 0.2 times of.
[0090] In this embodiment, at the junction of the entrance section 21 and the turning section 22, the angle between the extension direction of the outer side of the entrance section 21 and the extension direction of the outer side of the turning section 22 is Set to be the angle between the reverse thrust airflow and the radial direction of the blade cascade 11 The outer dimensions of the reverse thrust volute are reduced under the premise that the restriction of the reverse thrust volute on the airflow ejection ability meets the preset requirements.
[0091] Refer to (b) in 1. Figure 5 In some embodiments, the angle between the inner extension direction of the outlet section 23 and the axis direction of the engine 10 is In this embodiment, the angle between the inner extension direction of the outlet section 23 and the axial direction of the engine 10 is It can be selected as the recommended value of the reverse thrust volute used in a 15-ton high bypass ratio turbofan aircraft engine, and the outline size of the reverse thrust volute can be reduced when the flow direction after the airflow is discharged meets the preset conditions.
[0092] Refer to (b) in 1. Figure 5, in some embodiments, the included angle between the guide vane 231 and the axis direction of the engine 10 is 16.5°. In this embodiment, the included angle between the guide vane 231 and the axis direction of the engine 10 can be selected as the recommended value of the reverse thrust volute used in a 15-ton large bypass ratio turbofan aeroengine, which is the same as the same.
[0093] Reference 1(b) to Figure 5 , in some embodiments, the included angle between the normal line of the cross-section of the outlet section 23 and the axis direction of the engine 10 is 15°. In this embodiment, the included angle between the normal line of the cross-section of the outlet section 23 and the axis direction of the engine 10 can be selected as the recommended value of the reverse thrust volute used in a 15-ton large bypass ratio turbofan aeroengine.
[0094] Reference 1(b) to Figure 5 , in some embodiments, the length of the outer side of the outlet section 23 along the extending direction of the outlet section 23 is L3, and the value of L3 is 350 - 500 mm. In this embodiment, considering the space of the test workshop and the manufacturing process, on the premise of ensuring that the air flow discharged from the outlet section 23 will not be re-sucked or entrained by the high-temperature air flow discharged from the engine core, selecting the length of the outer side of the outlet section 23 along the extending direction of the outlet section 23 as L3 to be 350 - 500 mm can reduce the size of the outlet section 23.
[0095] Figure 6 is a flowchart of some embodiments of the reverse thrust volute design method according to the present disclosure. Refer to Figure 1 (b) to Figure 6 , on the other hand of the embodiments of the present disclosure, a reverse thrust volute design method based on any of the above reverse thrust volutes is provided. In some embodiments, the reverse thrust volute design method includes: step S1 to step S2.
[0096] In step S1, the axial width H at the outlet of the cascade 11 is obtained out . In step S2, according to the axial width H at the outlet of the cascade 11 out and the second design factor K2, the width H1 of the inlet section 21 along the axis direction of the engine 10 is determined. Wherein, H1 = K2 * H out , and the value of the second design factor K2 is 1.9437 - 2.1483.
[0097] In this embodiment, by setting the width H1 of the inlet section 21 of the reverse thrust volute to be 1.9437 - 2.1483 times the axial width at the outlet of the cascade 11 of the engine 10, it helps to reduce the space profile occupied by the reverse thrust volute, reduce the weight of the housing, and avoid blocking the air flow and affecting the total pressure of the engine or causing leakage. While reducing the axial dimension of the reverse thrust volute, the total pressure difference and air flow leakage of the reverse thrust volute to the engine can still meet the test requirements, facilitating the movement of the reverse thrust volute by the staff during the experiment.
[0098] Reference Figure 1 of (b) to Figure 5 , in some embodiments, the value of the second design factor K2 is 2.046. In this embodiment, the width H1 of the inlet section 21 in the axial direction of the engine 10 axis is preferably 2.046 times the axial width H out at the outlet of the cascade 11. On the premise of meeting the performance requirements such as the total pressure difference and air leakage of the engine by the turbine volute, it can also reduce the size and weight of the reverse thrust volute, facilitate reducing the mechanical power required to move the reverse thrust volute during the operation of debugging the volute and the engine and inspecting the engine during the test period, and shorten the test cycle occupied by the removal and reinstallation of the reverse thrust volute.
[0099] Reference Figure 1 of (b) to Figure 5 , in some embodiments, the reverse thrust volute design method further includes: determining the width H2 of the turning section 22 in the axial direction of the engine 10 axis according to the width H1 of the inlet section 21 in the axial direction of the engine 10 axis and the third design factor K3; wherein, H2 = K3 * H1, and the value of the third design factor K3 is 0.5282 - 0.5838.
[0100] In this embodiment, by setting the width H2 at the beginning of the turning section 22 to be 0.5282 - 0.5838 times the width H1 at the beginning of the inlet section 21, the initial size of the turning section of the reverse thrust volute can be reduced, and the air flow can be prevented from being blocked, which affects the total pressure of the engine or causes leakage. On the premise of meeting the requirements that the impact of the air flow on the reverse thrust volute is not too large and the pressure distribution and force condition on the inner surface of the reverse thrust volute meet the test requirements, the reverse thrust volute is more convenient to move during the operation of debugging the volute and the engine and inspecting the engine during the test period.
[0101] Reference Figure 1 of (b) to Figure 5 , in some embodiments, the value of the third design factor K3 is 0.556. The width H2 of the turning section 22 in the axial direction of the engine 10 axis is preferably 0.556 times the width H1 of the inlet section 21, so as to reduce the contour size and weight of the volute while meeting the impact condition of the air flow on the inner surface of the reverse thrust volute.
[0102] Reference Figure 1 of (b) to Figure 5 , in some embodiments, the reverse thrust volute design method further includes: determining the distance L2 in the radial direction of the engine 10 between the turning section 22 and the inlet section 21 according to the width H1 of the inlet section 21 in the axial direction of the engine 10 axis and the fourth design factor K4. Wherein, L2 = K4 * H1, and the value of the fourth design factor K4 is 0.7695 - 0.8505.
[0103] In this embodiment, by setting the distance L2 between the turning section 22 and the inlet section 21 to be 0.7695 to 0.8505 times the width H1 of the inlet section 21, the radial dimension of the reverse thrust volute can be reduced, and under the limited ejector effect, the turning section 22 can be prevented from being impacted too much or the air flow cannot be smoothly discharged from the turning section 22. While meeting the requirement that the total pressure loss of the reverse thrust volute reaches the preset requirement, the radial dimension between the turning section 22, the inlet section 21 and the engine is reduced, which is beneficial to reducing the radial dimension and weight of the reverse thrust volute.
[0104] Reference Figure 1 of (b) to Figure 5 , in some embodiments, the value of the fourth design factor K4 is 0.81. In this embodiment, the distance L2 between the turning section 22 and the inlet section 21 along the radial direction of the engine 10 is preferably 0.81 times the width H1 of the inlet section 21, so as to further reduce the radial dimension and weight of the reverse thrust volute, save the mechanical power required to move the reverse thrust volute, and shorten the time occupied by the disassembly and assembly of the reverse thrust volute during the test.
[0105] Reference Figure 1 of (b) to Figure 5 , in some embodiments, the reverse thrust volute design method further includes: according to the maximum takeoff flow rate W of the engine 10 max and the first design factor K1, determine the distance L1 between the midpoint of the inlet section 21 and the midpoint of the outlet of the cascade 11 along the flow direction of the reverse thrust air flow. Wherein, L1 = K1 * W max , and the value of the first design factor K1 is 0.2579 to 0.2851.
[0106] In this embodiment, by setting the distance L1 between the midpoint of the inlet section 21 and the midpoint of the outlet of the cascade 11 along the flow direction of the reverse thrust air flow at the outlet of the cascade 11 to be 0.2579 to 0.2851 times the maximum takeoff flow rate W of the engine 10 max , on the premise that the total pressure difference between the reverse thrust volute and the engine and the air flow leakage amount meet the preset requirements, the distance between the inlet of the reverse thrust volute and the reverse thrust outlet of the engine 10 is reduced, and the profile dimension occupied by the reverse thrust volute is reduced.
[0107] Reference Figure 1 of (b) to Figure 5 , in some embodiments, the value of the first design factor K1 is 0.2715. In this embodiment, the distance L1 between the midpoint of the inlet section 21 and the midpoint of the outlet of the cascade 11 along the flow direction of the reverse thrust air flow is preferably 0.2715 times the maximum takeoff flow rate W of the engine 10 max , so as to further reduce the profile dimension and weight of the reverse thrust volute, save the mechanical power required to move the reverse thrust volute, and shorten the time occupied by the disassembly and assembly of the reverse thrust volute during the test.
[0108] During the design process of the reverse thrust volute, through an iterative approach, while the reverse thrust volute meets the test requirements for various functions such as the total pressure difference of the engine, the air leakage volume, and the impact of the air flow on the volute, the space profile occupied by the reverse thrust volute is minimized as much as possible, the weight of the reverse thrust volute is reduced, and the load-bearing requirement of the housing self-weight on the support device is lowered, thereby obtaining the above parameters such as K1 - K4, L3, etc. And based on the above parameters and the recommended values of the reverse thrust volute used in a 15-ton large bypass ratio turbofan aeroengine, other structural parameters of the volute are determined. Compared with the traditional reverse thrust volute in this embodiment, the axial dimension is reduced by about 63%, the radial dimension is reduced by about 2%, and the weight is reduced by about 45% under the same material. It can reduce the occupied area of the reverse thrust volute outside the engine, facilitating the adjustment of the clearance between the volute and the engine during the test or the visual inspection of the engine during the test. Under the same working conditions, the power requirement for the mobile machinery is reduced by about 30%, and the time cycle for the removal and reinstallation of the reverse thrust volute is shortened.
[0109] So far, the embodiments of the present disclosure have been described in detail. To avoid obscuring the concept of the present disclosure, some details well known in the art have not been described. Those skilled in the art can fully understand how to implement the technical solutions disclosed herein based on the above description.
[0110] Although some specific embodiments of the present disclosure have been described in detail by way of examples, those skilled in the art should understand that the above examples are only for illustration and not for limiting the scope of the present disclosure. Those skilled in the art should understand that the above embodiments can be modified or some technical features can be equivalently replaced without departing from the scope and spirit of the present disclosure. The scope of the present disclosure is defined by the appended claims.
Claims
1. A reverse thrust volute, which is used for the reverse thrust test of an engine (10), is characterized in that, Comprising: An inlet section (21) for absorbing the reverse thrust airflow from the engine (10); An outlet section (23) for discharging the reverse thrust airflow towards the ejector barrel of the test stand; and A turning section (22) located between the inlet section (21) and the outlet section (23) for guiding the reverse thrust airflow to flow from the inlet section (21) to the outlet section (23); Among them, the width of the inlet section (21) in the axial direction of the engine (10) is H1, and the axial width at the outlet of the cascade (11) of the engine (10) is H out , and the width H1 of the inlet section (21) is out 1.9437 to 2.1483 times the width H at the outlet of the cascade (11).
2. The reverse thrust volute according to claim 1, characterized in that, The width H1 of the inlet section (21) in the axial direction of the engine (10) axis is 2.046 times the axial width H at the outlet of the cascade (11). out times that of 3. The reverse thrust volute according to claim 1 or 2, characterized in that, The width of the turning section (22) along the axis direction of the engine (10) is H2, and the width H2 of the turning section (22) is 0.5282 - 0.5838 times the width H1 of the inlet section (21).
4. The reverse thrust volute according to claim 3, characterized in that, The width H2 of the turning section (22) along the axis direction of the engine (10) is 0.556 times the width H1 of the inlet section (21).
5. The reverse thrust volute according to claim 1 or 2, characterized in that, The distance between the turning section (22) and the inlet section (21) along the radial direction of the engine (10) is L2, and the distance L2 between the turning section (22) and the inlet section (21) is 0.7695 - 0.8505 times the width H1 of the inlet section (21).
6. The reverse thrust volute according to claim 5, characterized in that, The distance L2 between the turning section (22) and the inlet section (21) along the radial direction of the engine (10) is 0.81 times the width H1 of the inlet section (21).
7. The reverse thrust volute according to claim 1 or 2, characterized in that, The distance between the midpoint of the inlet section (21) and the midpoint at the outlet of the cascade (11) along the flow direction of the reverse thrust airflow is L1, and the maximum takeoff flow rate of the engine (10) is W max , the distance L1 between the midpoint of the inlet section (21) and the midpoint at the outlet of the cascade (11) along the flow direction of the reverse thrust airflow at the outlet of the cascade (11) is 0.2579 to 0.2851 times the maximum takeoff flow rate W of the engine (10) max times.
8. The reverse thrust volute according to claim 7, characterized in that, The distance L1 between the midpoint of the inlet section (21) and the midpoint at the outlet of the cascade (11) along the flow direction of the reverse flow is 0.2715 times the maximum takeoff flow rate W of the engine (10). max times.
9. The reverse thrust volute according to claim 1 or 2, characterized in that, The inner curve radius of the turning section (22) is R1, and the inner curve radius R1 of the turning section (22) is 0.45 times the width H1 of the inlet section (21).
10. The reverse thrust volute according to claim 3, characterized in that, The inner curve radius of the turning section (22) is R1, the outer curve radius of the turning section (22) is R2, the inner curve radius R1 of the turning section (22) is 0.45 times the width H1 of the inlet section (21), and the outer curve radius R2 of the turning section (22) is the sum of the inner curve radius R1 of the turning section (22) and the width H2 of the turning section (22).
11. The reverse thrust volute according to claim 3, wherein, A plurality of guide vanes (231) are arranged at intervals inside the outlet section (23) along the direction perpendicular to the extension direction of the outlet section (23), the number of the guide vanes (231) is n, and the thickness of the guide vanes (231) is δ. where n = floor 12. The reverse thrust volute according to claim 11, characterized in that, The thickness δ of the guide vanes (231) is 10 - 40 millimeters.
13. The reverse thrust volute according to claim 1 or 2, characterized in that The included angle between the extension direction outside the inlet section (21) and the extension direction outside the turning section (22) at the connection of the inlet section (21) and the turning section (22) is The included angle between the flow direction of the reverse thrust air flow at the outlet of the cascade (11) and the radial direction of the cascade (11) is The included angle between the extension direction outside the inlet section (21) and the outside of the turning section (22) is 0.2 times the included angle between the reverse thrust air flow and the radial direction of the cascade (11). 14. The reverse thrust volute according to claim 1 or 2, characterized in that The included angle between the extending direction inside the said outlet section (23) and the axis direction of the said engine (10) is 16.5°.
15. The reverse thrust volute according to claim 11, characterized in that, The included angle between the guide vanes (231) and the axis direction of the engine (10) is 16.5°.
16. The reverse thrust volute according to claim 1 or 2, characterized in that, The included angle between the normal line of the cross-section of the outlet section (23) and the axis direction of the engine (10) is 15°.
17. The reverse thrust volute according to claim 1 or 2, characterized in that, The length of the outer side of the outlet section (23) along the extension direction of the outlet section (23) is L3, and the value of L3 is 350 - 500 millimeters.
18. A reverse flow volute design method based on the reverse flow volute according to any one of claims 1 to 17, characterized in that, Comprising: Obtain the axial width H at the outlet of the cascade (11) out ; According to the axial width H at the outlet of the cascade (11) out and the second design factor K2, determine the width H1 of the inlet section (21) in the axial direction of the engine (10); Among them, H1 = K2 * H out , and the value of the second design factor K2 is 1.9437 to 2.1483.
19. The reverse thrust volute design method according to claim 18, wherein The value of the second design factor K2 is 2.
046.
20. The reverse thrust volute design method according to claim 18, wherein Further comprising: Determining the width H2 of the turning section (22) along the axis direction of the engine (10) according to the width H1 of the inlet section (21) along the axis direction of the engine (10) and the third design factor K3; Wherein, H2 = K3 * H1, and the value of the third design factor K3 is 0.5282 - 0.5838.
21. The reverse thrust volute design method according to claim 20, wherein The value of the third design factor K3 is 0.
556.
22. The reverse thrust volute design method according to claim 18, wherein Further comprising: Determine the distance L2 in the radial direction of the engine (10) between the turning section (22) and the inlet section (21) according to the width H1 of the inlet section (21) in the axial direction of the engine (10) and the fourth design factor K4; wherein, L2 = K4 * H1, and the value of the fourth design factor K4 ranges from 0.7695 to 0.8505.
23. The reverse thrust volute design method according to claim 22, wherein The value of the fourth design factor K4 is 0.
81.
24. The reverse thrust volute design method according to claim 18, wherein, It further includes: Based on the maximum takeoff flow rate W of the engine (10) max and the first design factor K1, determine the distance L1 from the midpoint of the inlet section (21) to the midpoint at the outlet of the cascade (11) along the flow direction of the reverse flow air where L1 = K1 * W max , and the value of the first design factor K1 ranges from 0.2579 to 0.2851.
25. The reverse thrust volute design method according to claim 24, wherein The value of the first design factor K1 is 0.2715.