Temperature distortion evaluation method of coupling space-time dimension

Abstract

The invention provides a temperature distortion evaluation method for coupling space-time dimensionality, and belongs to the technical field of aero-engines, the method comprises the following steps: determining temperature distortion parameters having influence on the aerodynamic stability of an engine, the temperature distortion parameters comprising circumferential unevenness, radial unevenness and instantaneous temperature rise rate, coupling the temperature distortion parameters to construct an engine aerodynamic stability evaluation equation containing the temperature distortion parameters; and determining the circumferential non-uniformity, the radial non-uniformity and the instantaneous temperature rise rate so as to obtain an accurate engine aerodynamic stability evaluation equation. Compared with the prior art in which only temperature distortion intensity is adopted to evaluate the temperature distortion condition, the temperature distortion evaluation method provided by the invention comprehensively considers the influence of temperature distortion parameters such as circumferential non-uniformity, radial non-uniformity and instantaneous temperature rise rate on the engine; and the influence of temperature distortion on the aerodynamic stability of the engine can be accurately evaluated.

Description

Technical Field

[0001] The present application belongs to the field of aero-engines, and in particular relates to a temperature distortion assessment method coupled with time and space dimensions. Background Art

[0002] When an aircraft engine is working, the inlet temperature of the engine may be distorted by the inhalation of high-temperature gas. Severe distortion may lead to surge. In recent years, there have been many surge failures caused by the inhalation of high-temperature gas in aircraft engines, which have seriously affected the safety of engine operation.

[0003] In order to evaluate the temperature distortion of the engine, the prior art often only uses a single indicator of temperature distortion intensity, circumferential non-uniformity or temperature rise rate to describe the degree of temperature distortion and its impact on the aerodynamic stability of the engine.

[0004] However, using a single indicator to evaluate the degree of engine temperature distortion is too one-sided, including:

[0005] 1) The temperature distortion intensity is defined as the average relative temperature rise of the surface, which represents the degree of temperature rise of the engine inlet aerodynamic measurement section. The temperature distortion intensity has no direct effect on the engine aerodynamic stability. This method cannot consider the impact of time temperature distortion and space temperature distortion on the engine aerodynamic stability.

[0006] 2) Circumferential non-uniformity is defined as the relative ratio of the average temperature of the high temperature zone to the average temperature of the surface, that is, (average temperature of the high temperature zone - average temperature of the surface) / average temperature of the surface. This method cannot consider the impact of time-temperature distortion on the aerodynamic stability of the engine;

[0007] 3) The temperature rise rate is defined as the ratio of the maximum temperature rise measurement value in the high temperature zone to the time from the temperature jump to the maximum temperature rise value in the high temperature zone. It represents the temperature rise slope of the entire temperature rise stage and cannot consider the impact of the current time temperature distortion and space temperature distortion on the engine aerodynamic stability. Summary of the invention

[0008] The purpose of the present application is to provide a temperature distortion assessment method coupled with time and space dimensions to solve or alleviate at least one problem in the background technology.

[0009] The technical solution of the present application is: a temperature distortion assessment method coupled with time and space dimensions, comprising:

[0010] Determine the temperature distortion parameters that affect the aerodynamic stability of the engine, wherein the temperature distortion parameters include circumferential non-uniformity, radial non-uniformity, and instantaneous temperature rise rate, and couple the temperature distortion parameters to construct an engine aerodynamic stability evaluation equation containing the temperature distortion parameters:

[0011] The circumferential non-uniformity, radial non-uniformity and instantaneous temperature rise rate are determined, thereby obtaining an accurate engine aerodynamic stability evaluation equation.

[0012] In a preferred embodiment of the present application, the engine aerodynamic stability evaluation equation is:

[0013] Where W TD is the temperature integrated distortion value, is the radial unevenness, is the circumferential unevenness, is the instantaneous temperature rise rate, and a, b, and c are influencing factors.

[0014] In a preferred embodiment of the present application, the impact factor a≤0.1, the impact factor b≥1, and the impact factor c≥1.

[0015] In a preferred embodiment of the present application, the radial unevenness Where, T 2FAV is the average surface temperature, θ is the angle; T r (θ) is the temperature function based on linear interpolation between data points; TAV i is the radial average temperature, It is the relative radius of the hub, which is the ratio of the hub radius to the rim radius.

[0016] In a preferred embodiment of the present application, the circumferential unevenness Where, T HAV is the average temperature in the high temperature zone;

[0017] In the preferred embodiment of the present application, the instantaneous temperature rise rate

[0018] Where, ΔT i is the difference between the average temperature of the "high temperature zone" at the current moment and the average temperature of the "high temperature zone" at the previous moment, Δτ m is the sampling frequency.

[0019] In a preferred embodiment of the present application, according to the temperature comprehensive distortion value W TD The required stability margin for compensating temperature distortion is calculated. The required stability margin ΔSM T =α T ×W TD , where α T is the temperature distortion sensitivity (influence coefficient). The required stability margin has a lower limit. When the required stability margin exceeds the lower limit, the engine will surge.

[0020] The temperature distortion evaluation method provided in the present application is different from the prior art which only uses the temperature distortion intensity to evaluate the temperature distortion. The present application comprehensively considers the influence of temperature distortion parameters such as circumferential non-uniformity, radial non-uniformity, and instantaneous temperature rise rate on the engine, and can accurately evaluate the influence of temperature distortion on the aerodynamic stability of the engine, which is of great significance for screening the engine's resistance to temperature distortion. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical solutions and advantages of the implementation of this application clearer, the technical solutions in the embodiments of this application will be described in more detail below in combination with the specific contents in the embodiments of this application.

[0022] In order to solve the problem of surging caused by the engine inhaling high-temperature gas, the existing method of evaluating the impact of temperature distortion on engine working stability relies on the intensity of temperature distortion, and does not consider the impact of temperature rise rate, circumferential unevenness, radial unevenness, etc. on the aerodynamic stability of the engine. This application proposes a temperature distortion evaluation method that couples the time and space dimensions, which couples the impact of circumferential unevenness, radial unevenness, and instantaneous temperature rise rate on the aerodynamic stability of the engine, and includes all temperature distortion parameters. It not only comprehensively describes the temperature distortion situation, but also accurately evaluates the engine's ability to resist temperature distortion.

[0023] The temperature distortion evaluation method proposed in this application includes the following steps:

[0024] S100, determining temperature distortion parameters that affect the aerodynamic stability of the engine, wherein the temperature distortion parameters include circumferential non-uniformity, radial non-uniformity, and instantaneous temperature rise rate, and coupling the three temperature distortion parameters to construct an engine aerodynamic stability evaluation equation including the temperature distortion parameters:

[0025]

[0026] Where W TD is the temperature integrated distortion value, is the radial unevenness, is the circumferential unevenness, is the instantaneous temperature rise rate, a, b, c are influencing factors, a≤0.1, b, c≥1.

[0027] The engine aerodynamic stability evaluation equation of the present application covers spatial temperature distortion and temporal temperature distortion. The above-mentioned influencing factors are determined based on a large number of test results, and the effect of temperature distortion on the engine aerodynamic stability is accurately described.

[0028] S200, determining the circumferential unevenness, radial unevenness and instantaneous temperature rise rate, thereby obtaining the engine aerodynamic stability evaluation equation.

[0029] S210, radial non-uniformity

[0030] Where, T 2FAV is the average surface temperature, The unit is absolute temperature (K), θ is the angle;

[0031] T r (θ) is the temperature function based on linear interpolation between data points;

[0032] TAV i is the radial average temperature, The unit is absolute temperature (K);

[0033] It is the relative radius of the hub, which is the ratio of the hub radius to the rim radius.

[0034] S220, circumferential unevenness

[0035] Where, T HAV is the average temperature of the high temperature zone, in absolute temperature (K);

[0036] S230, instantaneous temperature rise rate

[0037] Where: is the instantaneous temperature rise rate, in units of absolute temperature per second (K / s);

[0038] ΔT i It is the difference between the average temperature of the "high temperature zone" at the current moment and the average temperature of the "high temperature zone" at the previous moment, in absolute temperature (K);

[0039] Δτ m The sampling frequency is in seconds (s).

[0040] The temperature comprehensive distortion value W in this application TD The larger it is, the worse the temperature distortion is.

[0041] Furthermore, according to the temperature comprehensive distortion value W TD The required stability margin for compensating temperature distortion can be calculated. The required stability margin has a lower limit. When the required stability margin exceeds the lower limit, the engine will surge.

[0042] Among them, the stability margin ΔSM is required T =α T ×W TD

[0043] In the formula, α T is the temperature distortion sensitivity (influence coefficient).

[0044] The temperature distortion evaluation method provided in the present application is different from the prior art which only uses the temperature distortion intensity to evaluate the temperature distortion. The present application comprehensively considers the influence of temperature distortion parameters such as circumferential non-uniformity, radial non-uniformity, and instantaneous temperature rise rate on the engine, and can accurately evaluate the influence of temperature distortion on the aerodynamic stability of the engine, which is of great significance for screening the engine's resistance to temperature distortion.

[0045] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A temperature distortion assessment method coupled with time and space dimensions, characterized in that: The method comprises: Determine the temperature distortion parameters that affect the aerodynamic stability of the engine, wherein the temperature distortion parameters include circumferential non-uniformity, radial non-uniformity, and instantaneous temperature rise rate, and couple the temperature distortion parameters to construct an engine aerodynamic stability evaluation equation containing the temperature distortion parameters: The circumferential non-uniformity, radial non-uniformity and instantaneous temperature rise rate are determined, thereby obtaining an accurate engine aerodynamic stability evaluation equation.

2. The temperature distortion assessment method of coupled time and space dimensions as claimed in claim 1, characterized in that: The engine aerodynamic stability evaluation equation is: Where W TD is the temperature integrated distortion value, is the radial unevenness, is the circumferential unevenness, is the instantaneous temperature rise rate, and a, b, and c are influencing factors.

3. The temperature distortion assessment method for coupled time and space dimensions as claimed in claim 2, characterized in that: The impact factor a≤0.1, the impact factor b≥1, and the impact factor c≥1.

4. The temperature distortion assessment method for coupled time and space dimensions according to claim 2 or 3, characterized in that: The radial non-uniformity Where, T 2FAV is the average surface temperature, θ is the angle; T r (θ) is the temperature function based on linear interpolation between data points; TAV i is the radial average temperature, It is the relative radius of the hub, which is the ratio of the hub radius to the rim radius.

5. The temperature distortion assessment method of coupled time and space dimensions as claimed in claim 4, characterized in that: The circumferential unevenness Where, T HAV is the average temperature in the high temperature zone.

6. The temperature distortion assessment method of coupled time and space dimensions as claimed in claim 5, characterized in that: The instantaneous temperature rise rate In the formula, ΔT i is the difference between the average temperature of the "high temperature zone" at the current moment and the average temperature of the "high temperature zone" at the previous moment, Δτ m is the sampling frequency.

7. The temperature distortion assessment method of coupled time and space dimensions as claimed in claim 6, characterized in that: According to the temperature comprehensive distortion value W TD The required stability margin for compensating temperature distortion is calculated. The required stability margin ΔSM T =α T ×W TD , where α T is the temperature distortion sensitivity (influence coefficient). The required stability margin has a lower limit. When the required stability margin exceeds the lower limit, the engine will surge.

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