A matching analysis method between non-adjustable inlet and aircraft engine flow characteristics

Abstract

The present application belongs to the technical field of flow matching compatibility analysis between a non-adjustable air inlet and an aircraft engine, and specifically relates to a flow matching compatibility analysis method between a non-adjustable air inlet and an aircraft engine, comprising: under the constraint of the non-adjustable air inlet, drawing an upper limit curve and a lower limit curve of the inlet flow W1r changing with the inlet temperature T1 when the aircraft engine is working stably; drawing flow characteristic curves of the inlet flow W1r changing with the inlet temperature T1 of various types of aircraft engines under the control law; if the flow characteristic curve corresponding to a certain type of aircraft engine exceeds the range of the upper limit curve and the lower limit curve, it is judged that the non-adjustable air inlet does not match the flow characteristic of the aircraft engine of this type; if the flow characteristic curve corresponding to a certain type of aircraft engine is within the range of the upper limit curve and the lower limit curve, it is judged that the non-adjustable air inlet matches the flow characteristic of the aircraft engine of this type.

Description

Technical Field

[0001] The present application belongs to the technical field of flow matching compatibility analysis between a non-adjustable air inlet and an aircraft engine, and specifically relates to a flow matching compatibility analysis method between a non-adjustable air inlet and an aircraft engine. Background Art

[0002] During the life cycle of some aircraft, it is necessary to replace multiple types of aircraft engines. The air required for the operation of the aircraft engine is provided through the air intake on the aircraft. The flow characteristics of the air intake need to match the flow characteristics of the aircraft engine, otherwise it will lead to a reduction in the performance of the aircraft engine, and even cause the aircraft engine to surge, leading to catastrophic accidents. Therefore, when replacing different types of aircraft engines, it is necessary to match the flow characteristics of the air intake with the flow characteristics of the replaced type of aircraft engine.

[0003] Currently, when replacing different types of aircraft engines, most of the methods used are to match and analyze the flow characteristics of the inlet duct with the flow characteristics of the replaced type of aircraft engine through a large number of tests, which is inefficient and takes a long time.

[0004] This application is proposed in view of the above-mentioned technical defects.

[0005] It should be noted that the disclosure of the above background technology content is only used to assist in understanding the inventive concept and technical solution of the present invention, and it does not necessarily belong to the prior art of this patent application. In the absence of clear evidence that the above content has been disclosed on the filing date of this application, the above background technology should not be used to evaluate the novelty and creativity of the present application. Summary of the invention

[0006] The purpose of the present application is to provide a method for analyzing the compatibility of a non-adjustable air inlet and an aircraft engine flow matching, so as to overcome or alleviate at least one of the known technical defects.

[0007] The technical solution of this application is:

[0008] A method for analyzing the matching of a non-adjustable air inlet and an aircraft engine flow characteristic, comprising:

[0009] Under the constraint of non-adjustable inlet duct, draw the upper limit curve and lower limit curve of the inlet flow rate W1r changing with the inlet temperature T1 when the aircraft engine is working stably;

[0010] Draw the flow characteristic curve of the inlet flow W1r changing with the inlet temperature T1 under the control law for various types of aircraft engines;

[0011] If the flow characteristic curve corresponding to a certain type of aircraft engine exceeds the range of the upper limit curve and the lower limit curve, it is determined that the non-adjustable inlet duct does not match the flow characteristic of the aircraft engine of this type;

[0012] If the flow characteristic curve corresponding to a certain type of aircraft engine is within the range of the upper limit curve and the lower limit curve, it is determined that the non-adjustable inlet duct matches the flow characteristic of the aircraft engine of this type.

[0013] According to at least one embodiment of the present application, in the above-mentioned non-adjustable inlet duct and aircraft engine flow characteristic matching analysis method, under the constraint of the non-adjustable inlet duct, the upper limit curve and the lower limit curve of the inlet flow W1r changing with the inlet temperature T1 when the aircraft engine is working stably are drawn, specifically:

[0014] Under the constraint of non-adjustable inlet duct, experiments were conducted with different types of aircraft engines to obtain the upper and lower limit curves of the inlet flow rate W1r changing with the inlet temperature T1 when the aircraft engine is working stably, and the curves were plotted.

[0015] According to at least one embodiment of the present application, in the above-mentioned non-adjustable inlet duct and aircraft engine flow characteristic matching analysis method, under the constraint of the non-adjustable inlet duct, the upper limit curve and the lower limit curve of the inlet flow W1r changing with the inlet temperature T1 when the aircraft engine is working stably are drawn, specifically:

[0016] Under the constraint of a non-adjustable inlet duct, the flow characteristic curve of a certain type of engine that can work stably under the control law, in which the inlet flow rate W1r changes with the inlet temperature T1, is used as a benchmark. The flow characteristics are changed to conduct experiments, and the upper and lower limit curves of the inlet flow rate W1r changing with the inlet temperature T1 when the aircraft engine works stably are obtained and plotted.

[0017] According to at least one embodiment of the present application, in the above-mentioned non-adjustable air inlet and aircraft engine flow characteristic matching analysis method, the upper limit curve and lower limit curve of the inlet flow W1r changing with the inlet temperature T1 when the aircraft engine is working stably are drawn under the constraint of the non-adjustable air inlet, and this is performed under the full-speed flight altitude conditions of the aircraft engine.

[0018] According to at least one embodiment of the present application, in the above-mentioned non-adjustable air inlet and aircraft engine flow characteristic matching analysis method, the aircraft engine full-speed flight altitude is obtained from the aircraft engine operating envelope.

[0019] This application has at least the following beneficial technical effects:

[0020] Provided is a method for analyzing the matching of a non-adjustable air inlet and an aircraft engine flow characteristic. The method is designed to draw an upper limit curve and a lower limit curve of an inlet flow W1r changing with an inlet temperature T1 when the aircraft engine is working stably under the constraint of the non-adjustable air inlet, and draw flow characteristic curves of the inlet flow W1r changing with the inlet temperature T1 of various types of aircraft engines under the control law. By judging whether the flow characteristic curve corresponding to a certain type of aircraft engine exceeds the range of the upper limit curve and the lower limit curve, it is obtained whether the non-adjustable air inlet matches the flow characteristic of the type of aircraft engine. The method is fast and effective. When different types of aircraft engines are replaced during flight, the method is used to perform matching analysis on the flow characteristic of the air inlet and the flow characteristic of the replaced type of aircraft engine. A large number of frequent tests are no longer required. The method has high efficiency and can effectively shorten the working cycle. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of a method for analyzing the matching of a non-adjustable air inlet and an aircraft engine flow characteristic provided in an embodiment of the present application;

[0022] Figure 2 It is a schematic diagram of an upper limit curve and a lower limit curve of the inlet flow rate W1r changing with the inlet temperature T1 when the aircraft engine is working stably under the constraint of a non-adjustable inlet duct, and a flow characteristic curve of the inlet flow rate W1r changing with the inlet temperature T1 of a certain type of aircraft engine under a control law, provided in an embodiment of the present application;

[0023] Figure 3 is a schematic diagram of an aircraft engine operating envelope provided by an embodiment of the present application;

[0024] in,

[0025] W1r is the aircraft engine inlet flow rate;

[0026] T1 is the aircraft engine inlet temperature;

[0027] H is the flight altitude of the aircraft engine;

[0028] Ma is the flight speed of the aircraft engine.

[0029] In order to better illustrate this embodiment, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of the actual product. In addition, the drawings are only used for illustrative purposes and cannot be understood as limitations on this patent. DETAILED DESCRIPTION

[0030] In order to make the technical solution and advantages of the present application clearer, the technical solution of the present application will be further described in detail in detail and in detail in conjunction with the accompanying drawings. It can be understood that the specific embodiments described here are only partial embodiments of the present application, which are only used to explain the present application, not to limit the present application. It should be noted that, for the convenience of description, only the parts related to the present application are shown in the accompanying drawings, and other related parts can refer to the general design. In the absence of conflict, the embodiments in the present application and the technical features in the embodiments can be combined with each other to obtain new embodiments.

[0031] In addition, unless otherwise defined, the technical terms or scientific terms used in the description of this application shall be the common meanings understood by the general technicians in the field to which this application belongs. The words "upper", "lower", "left", "right", "center", "vertical", "horizontal", "inside", "outside" and other words indicating orientation used in the description of this application are only used to indicate the relative direction or positional relationship, and do not imply that the device or element must have a specific orientation, 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, so it cannot be understood as a limitation on this application. The "first", "second", "third" and similar terms used in the description of this application are only used for descriptive purposes to distinguish different components, and cannot be understood as indicating or implying relative importance. The similar words "one", "one" or "the" used in the description of this application should not be understood as an absolute limitation on quantity, but should be understood as the existence of at least one. The similar words "including" or "comprising" used in the description of this application mean that the elements or objects appearing in front of the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects.

[0032] In addition, it should be noted that, unless otherwise clearly specified and limited, the words "installed", "connected", "connected" and similar terms used in the description of this application should be understood in a broad sense. For example, the 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, an indirect connection through an intermediate medium, or the internal connection of two components. Technical personnel in the field can understand their specific meanings in this application according to the specific circumstances.

[0033] The following is combined with Figures 1 to 3 This application is described in further detail.

[0034] A method for analyzing the matching of a non-adjustable air inlet and an aircraft engine flow characteristic, comprising:

[0035] Under the constraint of non-adjustable inlet duct, draw the upper limit curve and lower limit curve of the inlet flow rate W1r changing with the inlet temperature T1 when the aircraft engine is working stably;

[0036] Draw the flow characteristic curve of the inlet flow W1r changing with the inlet temperature T1 under the control law for various types of aircraft engines;

[0037] If the flow characteristic curve corresponding to a certain type of aircraft engine exceeds the range of the upper limit curve and the lower limit curve, it is determined that the non-adjustable inlet duct does not match the flow characteristic of the aircraft engine of this type;

[0038] If the flow characteristic curve corresponding to a certain type of aircraft engine is within the range of the upper limit curve and the lower limit curve, it is determined that the non-adjustable inlet duct matches the flow characteristic of the aircraft engine of this type.

[0039] As for the method for analyzing the matching of the non-adjustable air inlet and the flow characteristics of an aircraft engine disclosed in the above-mentioned embodiment, it can be understood by those skilled in the art that the design thereof draws the upper limit curve and the lower limit curve of the inlet flow W1r varying with the inlet temperature T1 when the aircraft engine is working stably under the constraint of the non-adjustable air inlet, and draws the flow characteristic curve of the inlet flow W1r varying with the inlet temperature T1 of each type of aircraft engine under the control law. By judging whether the flow characteristic curve corresponding to a certain type of aircraft engine exceeds the range of the upper limit curve and the lower limit curve, it is determined whether the flow characteristics of the non-adjustable air inlet match that type of aircraft engine. The method is fast and effective. When different types of aircraft engines are replaced during flight, the method is used to perform matching analysis on the flow characteristics of the air inlet and the flow characteristics of the replaced type of aircraft engines. A large number of frequent tests are no longer required. The method has high efficiency and can effectively shorten the working cycle.

[0040] In some optional embodiments, in the above-mentioned non-adjustable inlet duct and aircraft engine flow characteristic matching analysis method, under the constraint of the non-adjustable inlet duct, the upper limit curve and the lower limit curve of the inlet flow W1r changing with the inlet temperature T1 when the aircraft engine is working stably are drawn, specifically:

[0041] Under the constraint of non-adjustable inlet duct, experiments were conducted with different types of aircraft engines to obtain the upper and lower limit curves of the inlet flow rate W1r changing with the inlet temperature T1 when the aircraft engine is working stably, and the curves were plotted.

[0042] In some optional embodiments, in the above-mentioned non-adjustable inlet duct and aircraft engine flow characteristic matching analysis method, under the constraint of the non-adjustable inlet duct, the upper limit curve and the lower limit curve of the inlet flow W1r changing with the inlet temperature T1 when the aircraft engine is working stably are drawn, specifically:

[0043] Under the constraint of a non-adjustable inlet duct, the flow characteristic curve of a certain type of engine that can work stably under the control law, in which the inlet flow rate W1r changes with the inlet temperature T1, is used as a benchmark. The flow characteristics are changed to conduct experiments, and the upper and lower limit curves of the inlet flow rate W1r changing with the inlet temperature T1 when the aircraft engine works stably are obtained and plotted.

[0044] In some optional embodiments, in the above-mentioned non-adjustable air inlet and aircraft engine flow characteristic matching analysis method, under the constraint of the non-adjustable air inlet, the upper limit curve and lower limit curve of the inlet flow W1r changing with the inlet temperature T1 when the aircraft engine is working stably are drawn, and this is carried out under the full-speed flight altitude conditions of the aircraft engine.

[0045] In some optional embodiments, in the above-mentioned non-adjustable inlet and aircraft engine flow characteristic matching analysis method, the full-speed flight altitude of the aircraft engine is obtained from the aircraft engine operating envelope. The operating envelope of a certain type of aircraft engine is as follows: Figure 3 As shown, its full-speed flight altitude is 10km-11km.

[0046] In a specific embodiment, under the constraint of the non-adjustable inlet duct, the aircraft engine works stably, and the upper limit curve and the lower limit curve of the inlet flow rate W1r changing with the inlet temperature T1 are as follows: Figure 2 As shown, it can be concluded that with the increase of the inlet temperature T1, the range between the upper limit curve and the lower limit curve gradually narrows. When the inlet temperature T1 corresponds to the aircraft engine flight speed of 1.5Ma, the range of change of the upper limit curve and the lower limit curve is 8%. When the inlet temperature T1 corresponds to the aircraft engine flight speed of 2.0Ma, the range of change of the upper limit curve and the lower limit curve is 6%.

[0047] The various embodiments in the specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0048] So far, the technical solution of the present 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 the present application is obviously not limited to these specific embodiments. Without departing from the principles of the present 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 fall within the scope of protection of the present application.

Claims

1. A method for analyzing the matching of a non-adjustable air inlet and an aircraft engine flow characteristics, characterized in that: include: Under the constraint of non-adjustable inlet duct, draw the upper limit curve and lower limit curve of the inlet flow rate W1r changing with the inlet temperature T1 when the aircraft engine is working stably; Draw the flow characteristic curve of the inlet flow W1r changing with the inlet temperature T1 under the control law for various types of aircraft engines; If the flow characteristic curve corresponding to a certain type of aircraft engine exceeds the range of the upper limit curve and the lower limit curve, it is determined that the non-adjustable inlet duct does not match the flow characteristic of the aircraft engine of this type; If the flow characteristic curve corresponding to a certain type of aircraft engine is within the range of the upper limit curve and the lower limit curve, it is determined that the non-adjustable air intake duct matches the flow characteristic of the aircraft engine of this type; Under the constraint of the non-adjustable inlet duct, the upper limit curve and the lower limit curve of the inlet flow rate W1r changing with the inlet temperature T1 when the aircraft engine is working stably are drawn, specifically: Under the constraint of a non-adjustable inlet duct, the flow characteristic curve of a certain type of engine that can work stably under the control law, in which the inlet flow rate W1r changes with the inlet temperature T1, is used as a benchmark. The flow characteristics are changed to conduct experiments, and the upper and lower limit curves of the inlet flow rate W1r changing with the inlet temperature T1 when the aircraft engine works stably are obtained and plotted.

2. The method for analyzing the matching of the non-adjustable air inlet and the flow characteristics of the aircraft engine according to claim 1, characterized in that: The above-mentioned drawing of the upper limit curve and the lower limit curve of the inlet flow rate W1r varying with the inlet temperature T1 under the constraint of the non-adjustable inlet duct in stable operation of the aircraft engine is carried out under the flight altitude condition of the aircraft engine in the full speed range.

3. The method for analyzing the matching of the non-adjustable air inlet and the flow characteristics of the aircraft engine according to claim 2 is characterized in that: The full-speed flight altitude of the aircraft engine is obtained from the aircraft engine operating envelope.

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