Engine temperature protection method and system based on fuel supply control

Abstract

The present application relates to a temperature protection method and system for an engine based on fuel supply control, wherein the temperature protection method for an engine based on fuel supply control includes: setting a yellow warning temperature T4ˊ of the total temperature T4 at the outlet of the main combustion chamber; setting a red limit temperature T4", where T4">T4ˊ; when the total temperature T4 at the outlet of the main combustion chamber exceeds the yellow warning temperature T4ˊ and lasts for more than tˊ, according to W=Wˊ×e ‑kt Oil cut-off is performed to reduce the fuel supply to the main combustion chamber, where W is the fuel supply to the main combustion chamber; Wˊ is the fuel supply to the main combustion chamber at the start of oil cut-off; k is the oil cut-off depth coefficient for the main combustion chamber; t is the duration of oil cut-off in the main combustion chamber, which ends when the total temperature T4 at the main combustion chamber outlet reaches T4ˊ-60℃; when the total temperature T4 at the main combustion chamber outlet exceeds the red limit temperature T4" and lasts for more than t", the fuel supply to the main combustion chamber is completely cut off, where t"

Description

Technical Field

[0001] The present application belongs to the technical field of fuel supply control of air-assisted jet propulsion systems and general regulation system design, and specifically relates to a temperature protection method and system for an engine based on fuel supply control. Background Art

[0002] Under stable working conditions, the engine's control system will effectively control the engine's speed, temperature, and pressure within the set range. However, under abnormal conditions, the temperature inside the engine will rise sharply, exacerbating the harsh working environment of the engine's combustion chamber, high-pressure turbine and other hot-end components, causing the hot-end components to be burned, thereby causing catastrophic consequences.

[0003] To prevent serious consequences from overheating in the engine, the current design uses a linear oil cut when the low-pressure turbine outlet temperature T6 exceeds the temperature. This linearly reduces the fuel supply to the main combustion chamber to lower the temperature in the engine. This technical solution has the following drawbacks:

[0004] 1) The low-pressure turbine outlet temperature T6 cannot effectively and timely reflect the severity of the temperature inside the engine. If the low-pressure turbine outlet temperature T6 is used as a reference to control the temperature inside the engine, in theory, when an abnormality occurs, the temperature of the temperature-severe parts inside the engine cannot be reduced in time, making it difficult to avoid the burning of the hot end components inside the engine.

[0005] 2) When the low-pressure turbine outlet temperature T6 exceeds the upper limit, a linear oil cut is used to linearly reduce the fuel supply to the main combustion chamber. However, in the abnormal situation where the temperature inside the engine rises sharply, this method cannot effectively curb the rising trend of the temperature inside the engine, and it is difficult to avoid the burning of the hot end components inside the engine. In addition, the process of reducing the fuel supply to the main combustion chamber is not smooth enough, which is prone to fuel pulsation and causes oscillating combustion in the main combustion chamber.

[0006] This application is proposed in view of the above-mentioned technical defects.

[0007] 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 the present application. In the absence of clear evidence that the above content has been disclosed on the filing date of the present application, the above background technology should not be used to evaluate the novelty and creativity of the present application. Summary of the Invention

[0008] The purpose of the present application is to provide an engine temperature protection method and system based on fuel supply control to overcome or alleviate at least one of the existing technical defects.

[0009] The technical solution of this application is:

[0010] On the one hand, a method for protecting an engine temperature based on fuel supply control is provided, comprising:

[0011] Set the yellow warning temperature T4ˊ of the main combustion chamber outlet total temperature T4;

[0012] Set the red limit temperature T4〞 of the main combustion chamber outlet total temperature T4, T4〞>T4ˊ;

[0013] When the total temperature T4 at the main combustion chamber outlet exceeds the yellow warning temperature T4ˊ and lasts for more than tˊ, according to W=Wˊ×e -kt Oil cut-off is performed to reduce the fuel supply to the main combustion chamber, where W is the fuel supply to the main combustion chamber; Wˊ is the fuel supply to the main combustion chamber at the start of oil cut-off; k is the oil cut-off depth coefficient for the main combustion chamber; and t is the duration of oil cut-off in the main combustion chamber, which ends when the total temperature T4 at the main combustion chamber outlet reaches T4ˊ-60°C.

[0014] When the total temperature T4 at the main combustion chamber outlet exceeds the red limit temperature T4", and the duration exceeds t", the fuel supply to the main combustion chamber is completely cut off, where t" <tˊ。

[0015] According to at least one embodiment of the present application, in the above-mentioned engine temperature protection method based on fuel supply control, T4ˊ=T40+△ˊ;

[0016] T4〞=T4ˊ+△〞;

[0017] in,

[0018] T40 is the safety control temperature of the total temperature T4 at the main combustion chamber outlet when the engine is operating normally and steadily;

[0019] △ˊ is the control margin of the yellow warning temperature T4ˊ, which is 30~40℃;

[0020] △" is the control margin of the red limit temperature T4", which is 20~30℃.

[0021] According to at least one embodiment of the present application, in the above-mentioned engine temperature protection method based on fuel supply control, tˊ is 0.1 to 0.3s;

[0022] t〞is taken as 0.01~0.1s.

[0023] According to at least one embodiment of the present application, in the above-mentioned engine temperature protection method based on fuel supply control, the total temperature T4 at the main combustion chamber outlet is calculated based on the fuel supply W of the main combustion chamber and the low-pressure turbine outlet temperature T6.

[0024] According to at least one embodiment of the present application, in the above-mentioned engine temperature protection method based on fuel supply control, k is 1-2.

[0025] Another aspect provides an engine temperature protection system based on fuel supply control, comprising:

[0026] Yellow warning temperature configuration module, used to set the yellow warning temperature T4ˊ of the main combustion chamber outlet total temperature T4;

[0027] The red limit temperature configuration module is used to configure the red limit temperature T4" of the main combustion chamber outlet total temperature T4, T4">T4ˊ;

[0028] The fuel supply control module is connected to the engine control system and calculates the total temperature T4 at the main combustion chamber outlet based on the fuel supply W of the main combustion chamber and the low-pressure turbine outlet temperature T6;

[0029] When the total temperature T4 at the main combustion chamber outlet exceeds the yellow warning temperature T4ˊ and lasts for more than tˊ, according to W=Wˊ×e -kt Oil cut-off is performed to reduce the fuel supply to the main combustion chamber, where W is the fuel supply to the main combustion chamber; Wˊ is the fuel supply to the main combustion chamber at the start of oil cut-off; k is the oil cut-off depth coefficient for the main combustion chamber; and t is the duration of oil cut-off in the main combustion chamber, which ends when the total temperature T4 at the main combustion chamber outlet reaches T4ˊ-60°C.

[0030] When the total temperature T4 at the main combustion chamber outlet exceeds the red limit temperature T4", and the duration exceeds t", the fuel supply to the main combustion chamber is completely cut off, where t" <tˊ。

[0031] This application has at least the following beneficial technical effects:

[0032] Provided is a temperature protection method for an engine based on fuel supply control. The method is designed to control the temperature inside the engine using the total temperature T4 at the main combustion chamber outlet as a reference. The method can well and promptly reflect the severity of the temperature inside the engine, and use it as a reference to control the temperature inside the engine. When an abnormality occurs, the temperature of the temperature-severe parts inside the engine can be timely reduced, reducing the possibility of ablation of the hot end components inside the engine, avoiding fuel vibration and pulsation, and being able to control interference between measures.

[0033] In addition, a temperature protection system for an engine based on fuel supply control is provided, which is used to implement the above-mentioned temperature protection method for an engine based on fuel supply control. Its technical effects can refer to the technical effects of the relevant parts of the temperature protection method for an engine based on fuel supply control, and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1Schematic diagram of an engine temperature protection method based on fuel supply control provided in an embodiment of the present application;

[0035] Figure 2 Schematic diagram of the functional relationship between the total temperature T4 at the main combustion chamber outlet and the total temperature T2 at the engine inlet during normal steady-state operation provided by an embodiment of the present application;

[0036] Figure 3 It is a schematic diagram of the engine temperature protection system based on fuel supply control provided in an embodiment of the present application.

[0037] 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 should not be understood as limiting this application. DETAILED DESCRIPTION

[0038] To make the technical solution and its advantages of the present application clearer, the technical solution of the present application will be described in further detail below in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are only some embodiments of the present application and are only used to explain the present application, not to limit the present application. It should be noted that, for ease 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 of the present application and the technical features in the embodiments can be combined with each other to obtain new embodiments.

[0039] In addition, unless otherwise defined, the technical or scientific terms used in the description of this application should have the ordinary meanings understood by those of ordinary skill in the art to which this application belongs. The words "upper," "lower," "left," "right," "center," "vertical," "horizontal," "inner," and "outer" used in the description of this application are only used to indicate relative directions or positional relationships, and do not imply that the device or component must have a specific orientation, be constructed, or operate in a specific orientation. When the absolute position of the described object changes, its relative positional relationship may also change accordingly. Therefore, they should not be understood as limitations on this application. The words "first," "second," "third," and similar terms used in the description of this application are used only for descriptive purposes to distinguish different components and should not be understood to indicate or imply relative importance. The words "one," "an," or "the" used in the description of this application should not be understood as absolute limitations on quantity, but should be understood as meaning the presence of at least one. The words "include" or "comprises" used in the description of this application mean that the element or object listed before the word includes the elements or objects listed after the word and their equivalents, but does not exclude other elements or objects.

[0040] In addition, it should be noted that, unless otherwise clearly stipulated and limited, the words "install", "connect", "connect" 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 a connection between two components. Technical personnel in the field can understand their specific meanings in this application according to the specific circumstances.

[0041] The following is combined with Figures 1 to 3 This application is described in further detail.

[0042] On the one hand, a temperature protection method for an engine based on fuel supply control is provided. Figure 1 Shown, including:

[0043] Set the yellow warning temperature T4ˊ of the main combustion chamber outlet total temperature T4. The yellow warning temperature T4ˊ may correspond to the temperature at which the main combustion chamber outlet total temperature needs to be controlled and lowered.

[0044] Set the red limit temperature T4" of the main combustion chamber outlet total temperature T4, T4">T4ˊ, the red limit temperature T4" can be the maximum temperature allowed for the main combustion chamber outlet total temperature under the limit state;

[0045] When the total temperature T4 at the main combustion chamber outlet exceeds the yellow warning temperature T4ˊ and lasts for more than tˊ, according to W=Wˊ×e -kt Oil cut-off is performed to reduce the fuel supply to the main combustion chamber, where W is the fuel supply to the main combustion chamber; Wˊ is the fuel supply to the main combustion chamber at the start of oil cut-off; k is the oil cut-off depth coefficient for the main combustion chamber; and t is the duration of oil cut-off in the main combustion chamber, which ends when the total temperature T4 at the main combustion chamber outlet reaches T4ˊ-60°C.

[0046] When the total temperature T4 at the main combustion chamber outlet exceeds the red limit temperature T4", and the duration exceeds t", the fuel supply to the main combustion chamber is completely cut off, where t" <tˊ。

[0047] As for the temperature protection method based on fuel supply control of the engine disclosed in the above embodiment, it can be understood by those skilled in the art that its design uses the total temperature T4 at the main combustion chamber outlet as a reference to control the temperature inside the engine. Compared with the low-pressure turbine outlet temperature T6, the total temperature T4 at the main combustion chamber outlet can well and promptly reflect the severity of the temperature inside the engine. By using it as a reference to control the temperature inside the engine, when an abnormality occurs, the temperature of the temperature-severe parts of the engine can be reduced in time, thereby reducing the possibility of erosion of the hot end components inside the engine.

[0048] For the temperature protection method of the engine based on fuel supply control disclosed in the above embodiments, those skilled in the art can understand that when the total temperature T4 at the outlet of the main combustion chamber exceeds the yellow warning temperature T4ˊ, fuel is cut off non-linearly, and the fuel supply to the main combustion chamber is reduced non-linearly. Compared with the linear fuel cut-off method, it can effectively curb the rising trend of the temperature in the engine, and the non-linear fuel cut-off method is W = Wˊ×e -kt , which conforms to the natural law, can make the fuel quantity decrease smoothly during the whole fuel cut-off process, and can avoid fuel vibration and pulsation. In addition, when the total temperature T4 at the outlet of the main combustion chamber exceeds the red limit temperature T4〞, the fuel supply to the main combustion chamber is directly and completely cut off. The fuel supply of the engine is controlled in zones as a whole with the total temperature T4 at the outlet of the main combustion chamber as a reference, and the yellow warning temperature T4ˊ and the red limit temperature T4〞 are used as the reference respectively. For the abnormal situation of the rapid increase of the temperature in the engine, the temperature in the engine can be controlled in a timely and effective manner, and the hot-end components in the engine can be prevented from being ablated.

[0049] For the temperature protection method of the engine based on fuel supply control disclosed in the above embodiments, those skilled in the art can understand that when the total temperature T4 at the outlet of the main combustion chamber exceeds the yellow warning temperature T4ˊ and the duration exceeds tˊ, measures are taken to cut off the fuel supply to the main combustion chamber, and when the total temperature T4 at the outlet of the main combustion chamber exceeds the red limit temperature T4〞 and the duration exceeds t〞, measures are taken to completely cut off the fuel supply to the main combustion chamber, and t〞 < tˊ, which can avoid interference between the measures for controlling the temperature in the engine in zones.

[0050] In some optional embodiments, in the above temperature protection method of the engine based on fuel supply control, the yellow warning temperature T4ˊ and the red limit temperature T4〞 can be given based on experience, or can be calculated by referring to the following method:

[0051] T4ˊ = T40 + △ˊ;

[0052] T4〞 = T4ˊ + △〞;

[0053] Among them,

[0054] T40 is the safety control temperature of the total temperature T4 at the outlet of the main combustion chamber when the engine is operating in a normal steady state. It can be obtained by calculating the engine steady-state performance simulation model and retaining a certain temperature margin, and can be characterized as a function of the total temperature T2 at the engine inlet, such as Figure 2 shown;

[0055] △ˊ is the control margin of the yellow warning temperature T4ˊ, taking 30-40°C;

[0056] △〞 is the control margin of the red limit temperature T4〞, taking 20-30°C;

[0057] T4ˊ can also be obtained by calculating the engine transient performance simulation model and retaining a certain temperature margin.

[0058] In some optional embodiments, in the above-mentioned engine temperature protection method based on fuel supply control, tˊ is 0.1 to 0.3s;

[0059] t〞is taken as 0.01~0.1s.

[0060] In some optional embodiments, in the above-mentioned engine temperature protection method based on fuel supply control, the total temperature T4 at the main combustion chamber outlet is calculated using the fuel supply W of the main combustion chamber and the low-pressure turbine outlet temperature T6. The fuel supply W of the main combustion chamber and the low-pressure turbine outlet temperature T6 are used as measurement parameters, and the total temperature T4 at the main combustion chamber outlet can be calculated in real time using an onboard model.

[0061] In some optional embodiments, in the above-mentioned engine temperature protection method based on fuel supply control, k is 1-2.

[0062] On the other hand, a temperature protection system for an engine based on fuel supply control is provided. Figure 3 Shown, including:

[0063] Yellow warning temperature configuration module, used to set the yellow warning temperature T4ˊ of the main combustion chamber outlet total temperature T4;

[0064] The red limit temperature configuration module is used to configure the red limit temperature T4" of the main combustion chamber outlet total temperature T4, T4">T4ˊ;

[0065] The fuel supply control module is connected to the engine control system and calculates the total temperature T4 at the main combustion chamber outlet based on the fuel supply W of the main combustion chamber and the low-pressure turbine outlet temperature T6;

[0066] When the total temperature T4 at the main combustion chamber outlet exceeds the yellow warning temperature T4ˊ and lasts for more than tˊ, according to W=Wˊ×e -kt Oil cut-off is performed to reduce the fuel supply to the main combustion chamber, where W is the fuel supply to the main combustion chamber; Wˊ is the fuel supply to the main combustion chamber at the start of oil cut-off; k is the oil cut-off depth coefficient for the main combustion chamber; and t is the duration of oil cut-off in the main combustion chamber, which ends when the total temperature T4 at the main combustion chamber outlet reaches T4ˊ-60°C.

[0067] When the total temperature T4 at the main combustion chamber outlet exceeds the red limit temperature T4", and the duration exceeds t", the fuel supply to the main combustion chamber is completely cut off, where t" <tˊ。

[0068] The temperature protection system of the engine based on fuel supply control disclosed in the above embodiment is used to implement the temperature protection method of the engine based on fuel supply control disclosed in the above embodiment. The description is relatively simple. For specific related matters, please refer to the relevant description of the temperature protection part of the engine based on fuel supply control. Its technical effects can also refer to the technical effects of the relevant part of the temperature protection method of the engine based on fuel supply control, which will not be repeated here.

[0069] In addition, technicians in the field should also be able to realize that the various modules of the engine temperature protection system based on fuel supply control disclosed in the embodiments of the present application can be implemented by electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, this application generally describes them according to their functions. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Technicians in the field can choose to adopt different methods to implement the described functions for each specific application and its actual constraints, but such implementation should not be considered to be beyond the scope of this application.

[0070] 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 referred to in detail.

[0071] 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 replacements to the relevant technical features, and the technical solutions after these changes or replacements will fall within the scope of protection of the present application.

Claims

1. A temperature protection method for an engine based on fuel supply control, characterized in that: include: Set the yellow warning temperature T4ˊ of the main combustion chamber outlet total temperature T4; Set the red limit temperature T4〞 of the main combustion chamber outlet total temperature T4, T4〞>T4ˊ; When the total temperature T4 at the main combustion chamber outlet exceeds the yellow warning temperature T4ˊ and lasts for more than tˊ, according to W=Wˊ×e -kt Oil cut-off is performed to reduce the fuel supply to the main combustion chamber, where W is the fuel supply to the main combustion chamber; Wˊ is the fuel supply to the main combustion chamber at the start of oil cut-off; k is the oil cut-off depth coefficient for the main combustion chamber; and t is the duration of oil cut-off in the main combustion chamber, which ends when the total temperature T4 at the main combustion chamber outlet reaches T4ˊ-60°C. When the total temperature T4 at the main combustion chamber outlet exceeds the red limit temperature T4", and the duration exceeds t", the fuel supply to the main combustion chamber is completely cut off, where t" <tˊ。 2. The engine temperature protection method based on fuel supply control according to claim 1, characterized in that: T4ˊ=T40+△ˊ; T4〞=T4ˊ+△〞; in, T40 is the safety control temperature of the total temperature T4 at the main combustion chamber outlet when the engine is operating normally and steadily; △ˊ is the control margin of the yellow warning temperature T4ˊ, which is 30~40℃; △" is the control margin of the red limit temperature T4", which is 20~30℃.

3. The engine temperature protection method based on fuel supply control according to claim 1, characterized in that: tˊ is 0.1~0.3s; t〞is taken as 0.01~0.1s.

4. The engine temperature protection method based on fuel supply control according to claim 1, characterized in that: The total temperature T4 at the main combustion chamber outlet is calculated based on the fuel supply W of the main combustion chamber and the low-pressure turbine outlet temperature T6.

5. The engine temperature protection method based on fuel supply control according to claim 1, characterized in that: k is 1 to 2.

6. An engine temperature protection system based on fuel supply control, characterized in that: include: Yellow warning temperature configuration module, used to set the yellow warning temperature T4ˊ of the main combustion chamber outlet total temperature T4; The red limit temperature configuration module is used to configure the red limit temperature T4" of the main combustion chamber outlet total temperature T4, T4">T4ˊ; The fuel supply control module is connected to the engine control system and calculates the total temperature T4 at the main combustion chamber outlet based on the fuel supply W of the main combustion chamber and the low-pressure turbine outlet temperature T6; When the total temperature T4 at the main combustion chamber outlet exceeds the yellow warning temperature T4ˊ and lasts for more than tˊ, according to W=Wˊ×e -kt Oil cut-off is performed to reduce the fuel supply to the main combustion chamber, where W is the fuel supply to the main combustion chamber; Wˊ is the fuel supply to the main combustion chamber at the start of oil cut-off; k is the oil cut-off depth coefficient for the main combustion chamber; and t is the duration of oil cut-off in the main combustion chamber, which ends when the total temperature T4 at the main combustion chamber outlet reaches T4ˊ-60°C. When the total temperature T4 at the main combustion chamber outlet exceeds the red limit temperature T4", and the duration exceeds t", the fuel supply to the main combustion chamber is completely cut off, where t" <tˊ。

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