A method and system for determining the allowable area of ​​afterburner flaking

Abstract

The present invention relates to the field of aero-engine technology, and discloses a method and system for determining the allowable area of ​​flaky detached objects in an afterburner. According to the cross-sectional area and mechanical performance parameters of the suspension components in the afterburner, the dangerous energy of the flaky detached objects that damage the suspension components is determined, and then according to the inlet position of the afterburner and the axial position of the suspension components in the afterburner, the maximum kinetic energy per unit area of ​​the flaky detached objects from the detaching movement to the collision with the suspension components is obtained; according to the dangerous energy, the maximum kinetic energy per unit area, and the strain rate requirement value and elongation at tensile failure of the suspension components after the collision, the initial value of the allowable area of ​​the flaky detached objects that damage the suspension components is analyzed and obtained. The collision damage assessment of the flow channel detached contents to the downstream objects can be carried out simply and efficiently, providing a guiding basis for formulating the initial damage tolerance standard of the afterburner; and the analysis process saves a lot of calculation time through dynamic simulation analysis.

Description

Technical Field

[0001] The invention relates to the technical field of aeroengines, and discloses a method and a system for determining an allowable area of ​​flaky detached matter in an afterburner. Background Art

[0002] The afterburner chamber can provide more than 50% of the engine thrust and plays an important role. This component uses a large number of thin-walled components of about 1.0 mm. With the long-term use of the engine, the thin-walled components are cracked and fall off due to ablation, vibration, thermal deformation, etc. The resulting metal flakes fall off and enter the flow channel, which may cause collision damage to the downstream injection rod or stabilizer. For details, see Figure 1 As shown, it will cause serious engine failure and bring great hidden dangers to flight safety. If the components are replaced or disassembled for repair once the inspection finds cracks or a tendency to fall off, it will bring huge maintenance and economic costs. Therefore, the engineering department refers more to the development experience to formulate damage tolerance standards and determine the preliminary falling area. It is also necessary to carry out a large number of whole-machine tests to continuously revise the damage tolerance standards, which will bring certain technical risks and high test costs.

[0003] Therefore, it is extremely important to determine the area size of the afterburner's fallen contents. Currently, there are no patents or related literature on the method for determining the area size of the afterburner's fallen contents, and there is no relatively open and simple method to specifically evaluate the collision damage of the afterburner's fallen contents. Summary of the invention

[0004] The purpose of the present invention is to provide a method and system for determining the allowable area of ​​flaky debris in an afterburner, which can simply and efficiently carry out collision damage assessment of flow path flaked objects on downstream objects, and provide guidance for formulating the initial damage tolerance standard of the afterburner; and the analysis process saves a lot of computing time through dynamic simulation analysis.

[0005] In order to achieve the above technical effects, the technical solution adopted by the present invention is:

[0006] A method for determining an allowable area of ​​afterburner flaking material, comprising:

[0007] Determine the hazardous energy of the flaky material that damages the suspension components based on the cross-sectional area and mechanical performance parameters of the suspension components in the afterburner; the suspension components include the fuel injection rod and the flame stabilizer;

[0008] According to the inlet position of the afterburner chamber and the axial position of the suspension components in the afterburner chamber, the maximum kinetic energy per unit area of ​​the flaky detached object in the stroke from the detachment movement to the collision with the corresponding suspension components is obtained;

[0009] According to the hazardous energy, the maximum kinetic energy per unit area, and the required strain rate value and the elongation at tensile failure of the corresponding suspension components after collision, an initial value of the allowable area of ​​the flaky detached objects that damage the suspension components is obtained by analysis;

[0010] The minimum value among the initial values ​​of the flake-off allowable area is selected and determined as the flake-off allowable area for the afterburner.

[0011] Furthermore, the dangerous energy of the flaked material that damages the suspension parts ,in For the The cross-sectional area of ​​the suspension components, For the The impact toughness of the materials of each suspension component.

[0012] Furthermore, the maximum kinetic energy per unit area of ​​the flaky object during the movement from falling to colliding with the suspension component is ,in The flakes fall off from the inner cone at the inlet of the afterburner and move to the The movement distance of each suspension component along the airflow direction during the collision; is the axial position of the afterburner flow field The air flow density at is the axial position of the afterburner flow field The air flow velocity at is the differential symbol.

[0013] Furthermore, the initial value of the flaking allowable area ,in, The flaky debris destroyed the The critical drop-off area of ​​each suspension component, , For the The required strain rate value of each suspension component after collision, For the The elongation of a suspension component at tensile failure.

[0014] In order to achieve the above technical effects, the present invention also provides a system for determining the allowable area of ​​afterburner flaking objects, comprising:

[0015] The first analysis module is used to determine the dangerous energy of the flaky falling objects that damage the suspension parts according to the cross-sectional area and mechanical performance parameters of the suspension parts in the afterburner; the suspension parts include the fuel injection rod and the flame stabilizer;

[0016] The second analysis module is used to obtain the maximum kinetic energy per unit area of ​​the flaky detached object in the stroke from the detachment movement to the collision with the corresponding suspension component according to the inlet position of the afterburner and the axial position of the suspension component in the afterburner;

[0017] A third analysis module is used to analyze and obtain an initial value of an allowable area of ​​flaky debris that damages suspension components based on the hazardous energy, the maximum kinetic energy per unit area, and the required strain rate and elongation at tensile failure of the corresponding suspension components after collision;

[0018] The output module is used to select the minimum value among the initial values ​​of the flake shedding allowable area and determine it as the flake shedding allowable area of ​​the afterburner.

[0019] Furthermore, in the first analysis module, the dangerous energy of the flaky falling objects that damage the suspension parts ,in For the The cross-sectional area of ​​the suspension components, For the The impact toughness of the materials of each suspension component.

[0020] Furthermore, the maximum kinetic energy per unit area of ​​the flaky object during the movement from falling to colliding with the suspension component is ,in The flakes fall off from the inner cone at the inlet of the afterburner and move to the The movement distance of each suspension component along the airflow direction during the collision; is the axial position of the afterburner flow field The air flow density at is the axial position of the afterburner flow field The air flow velocity at is the differential symbol.

[0021] Furthermore, in the third analysis module, the initial value of the flaky material allowable area is ,in, The flaky debris destroyed the The critical drop-off area of ​​each suspension component, , For the The required strain rate value of each suspension component after collision, For the The elongation of a suspension component at tensile failure.

[0022] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention determines the dangerous energy of the flaky falling objects that damage the suspension parts according to the cross-sectional area and mechanical performance parameters of the suspension parts in the afterburner, and then obtains the maximum kinetic energy per unit area of ​​the flaky falling objects from the falling movement to the collision with the suspension parts according to the inlet position of the afterburner and the axial position of the suspension parts in the afterburner; according to the dangerous energy, the maximum kinetic energy per unit area, the strain rate requirement value after the collision of the suspension parts, and the elongation at tensile failure, the initial value of the allowable area of ​​the flaky falling objects that damage the suspension parts is analyzed and obtained. The collision damage assessment of the falling objects in the flow channel to the downstream objects can be carried out simply and efficiently, providing a guiding basis for the formulation of the initial damage tolerance standard of the afterburner; and the analysis process saves a lot of calculation time through dynamic simulation analysis, especially in the process of formulating the damage standard of thin-walled hot parts, it avoids the technical risks of blindly referring to foreign designs, and can provide reference indicators for subsequent maintenance in service. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 Flow chart of a method for determining the allowable area of ​​afterburner flaking in Example 1 or 2;

[0024] Figure 2 The structure block diagram of the system for determining the allowable area of ​​afterburner flaking in Example 1;

[0025] Figure 3 A schematic diagram of the motion trajectory of the flake-like falling objects at the afterburner inlet in Example 1 or 2;

[0026] Among them, 1. injection rod; 2. stabilizer; 3. inner cone; 4. flaky debris; 5. first analysis module; 6. second analysis module; 7. third analysis module; 8. output module. DETAILED DESCRIPTION

[0027] The present invention is further described in detail below in conjunction with the embodiments and drawings. However, it should not be understood that the scope of the above subject matter of the present invention is limited to the following embodiments, and all technologies realized based on the content of the present invention belong to the scope of the present invention.

[0028] Example 1

[0029] See also Figure 1-Figure 3 , a method for determining the allowable area of ​​afterburner flaking, comprising:

[0030] Determine the dangerous energy of the flaky falling objects 4 that damage the suspension components according to the cross-sectional area and mechanical performance parameters of the suspension components in the afterburner; the suspension components include the spray rod 1 and the flame stabilizer 2;

[0031] According to the inlet position of the afterburner chamber and the axial position of the suspension components in the afterburner chamber, the maximum kinetic energy per unit area of ​​the flaky falling object 4 in the stroke from falling motion to collision with the corresponding suspension components is obtained;

[0032] According to the dangerous energy, the maximum kinetic energy per unit area, and the required strain rate value and the elongation rate at tensile failure of the corresponding suspension components after collision, the initial value of the allowable area of ​​the flaky detached objects 4 that damage the suspension components is obtained by analysis;

[0033] The minimum value among the initial values ​​of the allowable area of ​​the flake-like debris 4 is selected and determined as the allowable area of ​​the afterburner flake-like debris 4.

[0034] The most likely and most dangerous objects of the falling objects in the afterburner flow passage are the fuel injection rod 1 and the stabilizer 2. The fuel injection rod 1 or the stabilizer 2 may collide and break, and the fuel may leak and cause abnormal combustion, which may cause the greatest danger. When the falling objects 4 collide in a perpendicular tangential manner, the fuel injection rod 1 is most likely to be sheared off, which is the most dangerous contact mode. Therefore, in this embodiment, the dangerous energy of the falling objects 4 that damage the suspension components is determined based on the cross-sectional area and mechanical performance parameters of the suspension components in the afterburner, and then the energy of the falling objects 4 that damage the suspension components is determined based on the cross-sectional area and mechanical performance parameters of the suspension components in the afterburner. The maximum kinetic energy per unit area of ​​the flaky object 4 from the falling motion to the collision with the suspension parts is obtained by the inlet position of the afterburner and the axial position of the suspension parts in the afterburner; the critical falling area of ​​the flaky object 4 is obtained by analysis; finally, according to the critical falling area and the strain rate requirement value and elongation at tensile failure after the collision of the suspension parts, the initial value of the allowable area of ​​the flaky object 4 is obtained by analysis, and the minimum value of the initial value of the allowable area of ​​the flaky object 4 is selected to determine the allowable area of ​​the flaky object 4 in the afterburner. The collision damage assessment of the flow channel shed contents to the downstream objects can be carried out simply and efficiently, providing a guiding basis for the formulation of the initial damage tolerance standard of the afterburner; and the analysis process saves a lot of calculation time through dynamic simulation analysis, especially in the process of formulating the damage standard of thin-walled hot parts, avoiding the technical risks of blindly referring to foreign designs, and can provide reference indicators for subsequent maintenance in service.

[0035] Based on the same inventive concept, this embodiment also provides a system for determining the allowable area of ​​afterburner flaky debris 4, comprising:

[0036] The first analysis module 5 is used to determine the dangerous energy of the flaky falling objects 4 that damage the suspension components according to the cross-sectional area and mechanical performance parameters of the suspension components in the afterburner; the suspension components include the spray rod 1 and the flame stabilizer 2;

[0037] The second analysis module 6 is used to obtain the maximum kinetic energy per unit area of ​​the flaky detached object 4 in the stroke from the detachment movement to the collision with the corresponding suspension component according to the inlet position of the afterburner and the axial position of the suspension component in the afterburner;

[0038] The third analysis module 7 is used to analyze and obtain the initial value of the allowable area of ​​the flaky detached objects 4 that damage the suspension parts according to the dangerous energy, the maximum kinetic energy per unit area, and the required strain rate value and the elongation rate at tensile failure of the corresponding suspension parts after collision;

[0039] The output module 8 is used to select the minimum value among the initial values ​​of the allowable area of ​​the flake-like detached objects 4 and determine it as the allowable area of ​​the flake-like detached objects 4 in the afterburner.

[0040] Example 2

[0041] See also Figure 1 and Figure 3 This embodiment takes the afterburner structure of a certain type of aircraft engine as an example to describe in detail the method for determining the allowable area of ​​flaky debris in the afterburner of the present invention. The specific determination steps are as follows:

[0042] Step 1: Determine the dangerous energy of the flaky falling objects 4 that damage the suspension components according to the cross-sectional area and mechanical performance parameters of the suspension components in the afterburner; the suspension components include the spray rod 1 and the flame stabilizer 2;

[0043] In this embodiment, the dangerous energy of the flaky falling objects that damage the suspension parts is ,in For the The cross-sectional area of ​​the suspension components, For the The impact toughness of the materials of each suspension component.

[0044] Step 2: according to the inlet position of the afterburner and the axial position of the suspension components in the afterburner, the maximum kinetic energy per unit area of ​​the flaky detached object 4 during the movement from detachment to collision with the corresponding suspension components is obtained;

[0045] In this embodiment, the maximum kinetic energy per unit area of ​​the flaky falling object 4 during the movement from falling to colliding with the suspension component is ,in The flake-like falling object 4 falls off from the inner cone 3 at the inlet position of the afterburner and moves to the position adjacent to the first The movement distance of each suspension component along the airflow direction during the collision; is the axial position of the afterburner flow field The air flow density at is the axial position of the afterburner flow field The air flow velocity at is the differential symbol.

[0046] Step 3: Analyze and obtain the initial value of the allowable area of ​​the flaky debris 4 that damages the suspension components according to the hazardous energy, the maximum kinetic energy per unit area, and the required strain rate and elongation at tensile failure of the corresponding suspension components after collision;

[0047] In this embodiment, the initial value of the allowable area of ​​the flaky material 4 is ,in, The flaky material 4 destroys the The critical drop-off area of ​​each suspension component, , For the The required strain rate value of each suspension component after collision, For the The elongation of a suspension component at tensile failure.

[0048] Step 4: Select the minimum value among the initial values ​​of the allowable area of ​​the flaked objects 4 and determine it as the allowable area of ​​the flaked objects 4 in the afterburner.

[0049] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for determining the allowable area of ​​afterburner flaking, characterized in that: include: According to the cross-sectional area and mechanical performance parameters of the suspension parts in the afterburner, the dangerous energy of the flaky falling objects that damage the suspension parts is determined; the suspension parts include the fuel injection rod and the flame stabilizer, and the dangerous energy of the flaky falling objects that damage the suspension parts is determined. ,in For the The cross-sectional area of ​​the suspension components, For the Material impact toughness of each suspension component; According to the inlet position of the afterburner and the axial position of the suspension parts in the afterburner, the maximum kinetic energy per unit area of ​​the flaky debris from the falling motion to the collision with the corresponding suspension parts is obtained. ,in The flakes fall off from the inner cone at the inlet of the afterburner and move to the The movement distance of each suspension component along the airflow direction during the collision; is the axial position of the afterburner flow field The air flow density at is the axial position of the afterburner flow field The air flow velocity at is the differential symbol; According to the dangerous energy, the maximum kinetic energy per unit area, and the required strain rate and elongation at tensile failure of the corresponding suspension components after collision, the initial value of the allowable area of ​​the flaky detached material that damages the suspension components is obtained by analysis. ,in, The flaky debris destroyed the The critical drop-off area of ​​each suspension component, , For the The required strain rate value of each suspension component after collision, For the Elongation of each suspension component at tensile failure; The minimum value among the initial values ​​of the flake-off allowable area is selected and determined as the flake-off allowable area for the afterburner.

2. A system for determining the allowable area of ​​afterburner flaking, characterized in that: include: The first analysis module is used to determine the dangerous energy of the flaked objects that damage the suspension parts according to the cross-sectional area and mechanical performance parameters of the suspension parts in the afterburner; the suspension parts include the fuel injection rod and the flame stabilizer, and the dangerous energy of the flaked objects that damage the suspension parts ,in For the The cross-sectional area of ​​the suspension components, For the Material impact toughness of each suspension component; The second analysis module is used to obtain the maximum kinetic energy per unit area of ​​the flaky detached object from the detachment movement to the collision with the corresponding suspension component according to the inlet position of the afterburner and the axial position of the suspension component in the afterburner. ,in The flakes fall off from the inner cone at the inlet of the afterburner and move to the The movement distance of each suspension component along the airflow direction during the collision; is the axial position of the afterburner flow field The air flow density at is the axial position of the afterburner flow field The air flow velocity at is the differential symbol; The third analysis module is used to analyze and obtain the initial value of the allowable area of ​​the flaky detached objects that damage the suspension parts according to the dangerous energy, the maximum kinetic energy per unit area, and the strain rate requirement value and the elongation rate at tensile failure of the corresponding suspension parts after collision. ,in, The flaky debris destroyed the The critical drop-off area of ​​each suspension component, , For the The required strain rate value of each suspension component after collision, For the Elongation of each suspension component at tensile failure; The output module is used to select the minimum value among the initial values ​​of the flake shedding allowable area and determine it as the flake shedding allowable area of ​​the afterburner.

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