A method for determining the outer channel total pressure loss of a dual-duct compressor of an aero-engine

Abstract

The application provides a method for determining the total pressure loss of an outer channel of a dual-duct compressor of an aero-engine, comprising: constructing a flow channel model of the dual-duct compressor to generate a calculation grid; configuring the total pressure, total temperature, airflow direction of the inlet of the flow channel of the dual-duct compressor, the converted flow rate of the outer channel, and the outlet static pressure of the inner channel; changing the converted flow rate of the outer channel, calculating the corresponding total pressure loss of the outer channel, and fitting to obtain a calculation formula of the total pressure loss of the outer channel and the converted flow rate of the outer channel; obtaining the relationship between the flow rate of the dual-duct compressor and the converted rotating speed, and the relationship between the flow rate of the inner channel and the converted rotating speed of the inner channel; measuring the temperature of the inlet of the flow channel of the dual-duct compressor and the inlet temperature of the inner channel, calculating the converted rotating speed of the dual-duct compressor and the converted rotating speed of the inner channel, and then calculating the flow rate of the dual-duct compressor and the flow rate of the inner channel, calculating the physical flow rate of the outer channel, measuring the inlet pressure of the inner channel, and calculating the converted flow rate of the outer channel; and calculating the total pressure loss of the outer channel by using the calculation formula of the total pressure loss of the outer channel and the converted flow rate of the outer channel.

Description

Technical Field

[0001] This application belongs to the technical field of determining the total pressure loss of the outer bypass of a dual-bypass compressor in an aero-engine, and specifically relates to a method for determining the total pressure loss of the outer bypass of a dual-bypass compressor in an aero-engine. Background Technology

[0002] Some types of aero engines are equipped with dual-bypass compressors. Dual-bypass compressors are a type of high-pressure compressor for variable cycle turbofan engines. By changing multiple adjustable mechanisms, the aerodynamic requirements of different engine cycle modes can be met.

[0003] The main difference between a dual-bypass compressor and a conventional compressor is that a conventional compressor only has an internal flow, while a dual-bypass compressor has an internal flow and an external flow after the first stage of power addition.

[0004] The outer bypass space of a dual-bypass compressor is compact, limiting the space for pressure measurement points. Furthermore, dual-bypass compressors need to adapt to different bypass ratios and operating ranges, resulting in drastic changes in the airflow direction at the outer bypass inlet, inevitably leading to separation. Pressure tests struggle to reflect the average value across the entire channel. Currently, obtaining the total pressure loss of the outer bypass solely through total pressure testing methods for dual-bypass compressors is inaccurate.

[0005] This application is made in view of the aforementioned technical deficiencies.

[0006] It should be noted that the above background information is only used to assist in understanding the inventive concept and technical solution of this invention, and it does not necessarily belong to the prior art of this patent application. In the absence of clear evidence that the above information was disclosed on the filing date of this application, the above background information should not be used to evaluate the novelty and inventiveness of this application. Summary of the Invention

[0007] The purpose of this application is to provide a method for determining the total pressure loss of the outer bypass of a twin-blowback compressor in an aero-engine, so as to overcome or mitigate at least one of the known technical defects.

[0008] The technical solution of this application is:

[0009] A method for determining the total pressure loss of the outer bypass of a dual-bypass compressor in an aero-engine, comprising:

[0010] Construct a flow channel model of a double-bypass compressor and generate a computational grid;

[0011] Configure the total pressure, total temperature, and airflow direction at the inlet of the dual-blowout compressor flow channel; the converted flow rate of the outer bypass; and the outlet static pressure of the inner bypass.

[0012] Calculate the corresponding total pressure loss of the culvert by changing the converted flow rate of the culvert.

[0013] By fitting the total pressure loss of each culvert and its corresponding equivalent flow rate, the calculation formulas for the total pressure loss and equivalent flow rate of the culvert are obtained.

[0014] Obtain the relationship between flow rate and converted speed of the double-bypass compressor, and the relationship between internal flow rate and internal converted speed;

[0015] The temperature at the inlet of the double-bend compressor flow channel and the temperature at the inlet of the internal cavity are measured, and the equivalent speed and the equivalent speed of the internal cavity of the double-bend compressor are calculated. Then, the flow rate and the internal cavity flow rate of the double-bend compressor are calculated.

[0016] The physical flow rate of the outer bypass is calculated from the flow rate of the double bypass compressor and the flow rate of the inner bypass. The inlet pressure of the inner bypass is measured, and then the converted flow rate of the outer bypass is calculated.

[0017] The total pressure loss of the duct is calculated using the formula for calculating the total pressure loss of the duct and the converted flow rate of the duct.

[0018] According to at least one embodiment of this application, the above-described method for determining the total pressure loss of the outer bypass of a dual-bypass compressor in an aero-engine is characterized in that...

[0019] The flow channel model of the dual-bypass compressor is constructed, and the computational grid of the outer bypass is refined in the generated computational grid.

[0020] According to at least one embodiment of this application, the above-described method for determining the total pressure loss of the outer bypass of a dual-bypass compressor in an aero-engine is characterized in that...

[0021] The total pressure, total temperature, and airflow direction at the inlet of the dual-duct compressor shown are calculated, along with the converted flow rate of the outer duct, the outlet static pressure of the inner duct, and the converted flow rate of the changed outer duct. The corresponding total pressure loss of the outer duct is calculated using the commercial turbomachinery aerodynamic simulation software NUMECA.

[0022] According to at least one embodiment of this application, the above-described method for determining the total pressure loss of the outer bypass of a dual-bypass compressor in an aero-engine is characterized in that...

[0023] The total pressure loss of each culvert and its corresponding equivalent flow rate are fitted to obtain the following formulas for calculating the total pressure loss and equivalent flow rate of the culvert:

[0024] δ bypass =α1W 27r 2 +α2W 27r +α3;

[0025] in,

[0026] δ bypass This refers to the total pressure loss of the ductwork.

[0027] W 27rCalculate the flow rate for the outer duct;

[0028] α1, α2, and α3 are fitting coefficients.

[0029] According to at least one embodiment of this application, the above-described method for determining the total pressure loss of the outer bypass of a dual-bypass compressor in an aero-engine is characterized in that...

[0030] The relationship between the flow rate and the equivalent speed of the dual-bend compressor, and the relationship between the internal flow rate and the internal equivalent speed, are obtained specifically through theoretical calculations or experimental methods.

[0031] According to at least one embodiment of this application, the above-described method for determining the total pressure loss of the outer bypass of a dual-bypass compressor in an aero-engine is characterized in that...

[0032] The calculations yielded the converted speed and internal converted speed of the dual-blowback compressor, specifically:

[0033]

[0034]

[0035] in,

[0036] n 23r Calculate the speed for a double-bend compressor;

[0037] T 23 This refers to the temperature at the inlet of the flow channel of the double-baffle compressor;

[0038] n 25r For internal import temperature;

[0039] T 25 The internal conversion speed is calculated.

[0040] According to at least one embodiment of this application, the above-described method for determining the total pressure loss of the outer bypass of a dual-bypass compressor in an aero-engine is characterized in that...

[0041] The physical flow rate of the outer bypass compressor is calculated from the flow rate of the double-blowback compressor and the flow rate of the inner bypass compressor, specifically as follows:

[0042] W 27 =W 23 -W 25 ;

[0043] in,

[0044] W 23 This refers to the flow rate of a dual-blowback compressor.

[0045] W 25 For intrinsic traffic;

[0046] W 27 For external duct physical flow.

[0047] This application has at least the following beneficial technical effects:

[0048] This paper presents a method for determining the total pressure loss of the outer bypass of a dual-bypass compressor in an aero-engine. Based on the dual-bypass compressor, and assuming the outer bypass geometry remains constant, the total pressure loss is only related to the converted flow rate of the outer bypass. The method involves deriving the total pressure loss of the outer bypass through simulation calculations at multiple converted flow rates. A formula for calculating the total pressure loss and converted flow rate is obtained through fitting. Furthermore, the converted flow rate of the outer bypass is calculated using the inlet temperature of the dual-bypass compressor flow channel, the inlet temperature of the inner casing, and the inlet pressure of the inner casing, thus yielding the total pressure loss with high accuracy. Attached Figure Description

[0049] Figure 1 This is a schematic diagram of the method for determining the total pressure loss of the outer bypass of a dual-bypass compressor in an aero-engine, provided in an embodiment of this application.

[0050] Figure 2 This is a schematic diagram of the total pressure loss and converted flow rate of the ductwork provided in the embodiments of this application. Detailed Implementation

[0051] To make the technical solution and advantages of this application clearer, the technical solution of this application will be described in a clearer and more complete manner below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only some embodiments of this application, and are only used to explain this application, not to limit this application. It should be noted that, for ease of description, only the parts related to this application are shown in the accompanying drawings. Other related parts can be referred to the general design. In the absence of conflict, the embodiments and technical features in the embodiments of this application can be combined with each other to obtain new embodiments.

[0052] Furthermore, unless otherwise defined, the technical or scientific terms used in this application description shall have the ordinary meaning understood by one of ordinary skill in the art to which this application pertains. The terms "upper," "lower," "left," "right," "center," "vertical," "horizontal," "inner," and "outer," etc., used in this application description to indicate relative direction or positional relationship are used only to indicate relative orientation or positional relationship, and do not imply that the device or component must have a specific orientation, or be constructed and operated in a specific orientation. When the absolute position of the described object changes, its relative positional relationship may also change accordingly, and therefore should not be construed as a limitation on this application. The terms "first," "second," "third," and similar terms used in this application description are used only for descriptive purposes to distinguish different components, and should not be construed as indicating or implying relative importance. The terms "a," "one," or "the," etc., used in this application description should not be construed as an absolute limitation on quantity, but should be construed as indicating the existence of at least one. The terms "including," "comprising," etc., used in this application description mean that the element or object preceding the word covers the element or object listed after the word and its equivalents, without excluding other elements or objects.

[0053] Furthermore, it should be noted that, unless otherwise explicitly specified and limited, terms such as “installation,” “connection,” and “linkage” used in the description of this application should be interpreted broadly. For example, a connection can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; or it can be a connection within two components. Those skilled in the art can understand its specific meaning in this application according to the specific circumstances.

[0054] The following is in conjunction with the appendix Figures 1-2 This application will be described in further detail.

[0055] Research has found that for a dual-bypass compressor, when the outer bypass geometry remains unchanged, the total pressure loss of the outer bypass is only related to the converted flow rate of the outer bypass. Based on this, this application provides the following method for determining the total pressure loss of the outer bypass of a dual-bypass compressor for aero-engines: Figure 1 As shown.

[0056] A flow path model of a dual-bypass compressor is constructed. This model is based on the actual flow path dimensions of the dual-bypass compressor and is a joint model of the inner and outer bypasses. A computational grid is generated. Due to the complexity of the flow in the outer bypass and its important focus, the computational grid of the outer bypass is refined.

[0057] Using the commercial turbomachinery aerodynamic simulation software NUMECA, calculation methods, mathematical models, materials, etc., were set, and calculation boundary conditions were established. The inlet boundary conditions were the total pressure, total temperature, and airflow direction at the inlet of the double-blowout compressor flow channel at a certain state point. Two boundary conditions were set for the inner and outer bypasses. The outlet boundary condition of the inner bypass was the required outlet static pressure, and the boundary condition of the outer bypass was the converted flow rate.

[0058] By gradually adjusting the converted flow rate of the duct, the calculation results for each state under the full flow range of the duct used are obtained, and the corresponding total pressure loss of the duct is obtained.

[0059] By fitting the total pressure loss of each culvert and its corresponding equivalent flow rate, the calculation formulas for the total pressure loss and equivalent flow rate of the culvert are obtained:

[0060] δ bypass =α1W 27r 2 +α2W 27r +α3;

[0061] in,

[0062] δ bypass This refers to the total pressure loss of the ductwork.

[0063] W 27r Calculate the flow rate for the outer duct;

[0064] α1, α2, and α3 are the fitting coefficients;

[0065] The relationship between total pressure loss of the duct and equivalent flow rate of the duct is as follows: Figure 2 As shown.

[0066] In a double-baffle compressor, it is difficult to test the inlet temperature and total pressure of the outer bypass. The converted flow rate of the outer bypass can be calculated from the inlet temperature of the flow channel, the inlet temperature of the inner bypass, and the inlet pressure of the inner bypass, as detailed below:

[0067] The relationship between flow rate and converted speed, and the relationship between internal flow rate and internal converted speed of a double-bend compressor are obtained by theoretical calculation or experimental methods.

[0068] By measuring the inlet temperature of the flow channel and the inlet temperature of the internal cavity of the double-bend compressor, the converted speed and the converted speed of the internal cavity of the double-bend compressor are calculated as follows:

[0069]

[0070]

[0071] in,

[0072] n 23r Calculate the speed for a double-bend compressor;

[0073] T23 This refers to the temperature at the inlet of the flow channel of the double-baffle compressor;

[0074] n 25r For internal import temperature;

[0075] T 25 To calculate the rotational speed based on the internal characteristics;

[0076] The flow rate and internal flow rate of the double-bypass compressor are calculated based on the relationship between the flow rate and the equivalent speed of the double-bypass compressor, and the relationship between the internal flow rate and the equivalent speed of the internal flow rate.

[0077] The physical flow rate of the outer bypass compressor is calculated from the flow rate of the double bypass compressor and the flow rate of the inner bypass compressor, as follows:

[0078] W 27 =W 23 -W 25 ;

[0079] in,

[0080] W 23 This refers to the flow rate of a dual-blowback compressor.

[0081] W 25 For intrinsic traffic;

[0082] W 27 For external duct physical flow;

[0083] The inlet pressure of the inner core is measured, and the converted flow rate of the outer core is calculated using the inlet pressure and temperature of the inner core and the physical flow rate of the outer core.

[0084] External conversion flow W 27 The formula δ is used to calculate the total pressure loss of the duct and the converted flow rate of the duct. bypass =α1W 27r 2 +α2W 27r +α3, calculate the total pressure loss δ of the outer duct. bypass .

[0085] The various embodiments in the specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0086] The technical solution of this application has been described in conjunction with the preferred embodiments shown in the accompanying drawings. Those skilled in the art should understand that the scope of protection of this application is obviously not limited to these specific embodiments. Without departing from the principles of this application, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will all fall within the scope of protection of this application.

Claims

1. A method for determining the total pressure loss of the outer bypass of a twin-bypass compressor in an aero-engine, characterized in that, include: Construct a flow channel model of a double-bypass compressor and generate a computational grid; Configure the total pressure, total temperature, and airflow direction at the inlet of the dual-blowout compressor flow channel; the converted flow rate of the outer bypass; and the outlet static pressure of the inner bypass. Calculate the corresponding total pressure loss of the culvert by changing the converted flow rate of the culvert. By fitting the total pressure loss of each culvert and its corresponding equivalent flow rate, the calculation formulas for the total pressure loss and equivalent flow rate of the culvert are obtained. Obtain the relationship between flow rate and converted speed of the double-bypass compressor, and the relationship between internal flow rate and internal converted speed; The temperature at the inlet of the double-bend compressor flow channel and the temperature at the inlet of the internal cavity are measured, and the equivalent speed and the equivalent speed of the internal cavity of the double-bend compressor are calculated. Then, the flow rate and the internal cavity flow rate of the double-bend compressor are calculated. The physical flow rate of the outer bypass is calculated from the flow rate of the double bypass compressor and the flow rate of the inner bypass. The inlet pressure of the inner bypass is measured, and then the converted flow rate of the outer bypass is calculated. The total pressure loss of the duct is calculated using the formula for calculating the total pressure loss of the duct and the converted flow rate of the duct.

2. The method for determining the total pressure loss of the outer bypass of a twin-bypass compressor in an aero-engine according to claim 1, characterized in that, The flow channel model of the dual-bypass compressor is constructed, and the computational grid of the outer bypass is refined in the generated computational grid.

3. The method for determining the total pressure loss of the outer bypass of a twin-bypass compressor in an aero-engine according to claim 1, characterized in that, The total pressure, total temperature, and airflow direction at the inlet of the dual-duct compressor shown are calculated, along with the converted flow rate of the outer duct, the outlet static pressure of the inner duct, and the converted flow rate of the changed outer duct. The corresponding total pressure loss of the outer duct is calculated using the commercial turbomachinery aerodynamic simulation software NUMECA.

4. The method for determining the total pressure loss of the outer bypass of a twin-bypass compressor in an aero-engine according to claim 1, characterized in that, The total pressure loss of each culvert and its corresponding equivalent flow rate are fitted to obtain the following formulas for calculating the total pressure loss and equivalent flow rate of the culvert: d bypass =α1W 27r 2 +α2W 27r +α3; in, δ bypass This refers to the total pressure loss of the ductwork. W 27r Calculate the flow rate for the outer duct; α1, α2, and α3 are fitting coefficients.

5. The method for determining the total pressure loss of the outer bypass of a twin-bypass compressor in an aero-engine according to claim 1, characterized in that, The relationship between the flow rate and the equivalent speed of the dual-bend compressor, and the relationship between the internal flow rate and the internal equivalent speed, are obtained specifically through theoretical calculations or experimental methods.

6. The method for determining the total pressure loss of the outer bypass of a twin-bypass compressor in an aero-engine according to claim 1, characterized in that, The calculations yielded the converted speed and internal converted speed of the dual-blowback compressor, specifically: in, n 23r Calculate the speed for a double-bend compressor; T 23 This refers to the temperature at the inlet of the flow channel of the double-baffle compressor; n 25r For internal import temperature; T 25 The internal conversion speed is calculated.

7. The method for determining the total pressure loss of the outer bypass of a twin-bypass compressor in an aero-engine according to claim 1, characterized in that, The physical flow rate of the outer bypass compressor is calculated from the flow rate of the double-blowback compressor and the flow rate of the inner bypass compressor, specifically as follows: IN 27 =In 23 -IN 25 ; in, W 23 This refers to the flow rate of a dual-blowback compressor. W 25 For intrinsic traffic; W 27 For external duct physical flow.

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