A method of correcting an air turbine engine display speed

Abstract

The application belongs to the field of aero-engine design and relates to a correction method for displaying the rotating speed of an aero gas turbine engine. The method comprises the following steps: firstly, obtaining the control plan value of the high-pressure relative physical rotating speed under the current engine intake temperature by linear interpolation according to the current engine intake temperature and the high-pressure relative physical rotating speed control plan; then, converting the control plan value of the high-pressure relative physical rotating speed into the control plan value of the high-pressure relative converted rotating speed; calculating the high-pressure relative converted rotating speed by calculating the high-pressure relative physical rotating speed n2 under the current engine intake temperature; setting the correction rotating speed segmented coefficient; calculating the segmented node rotating speed; and calculating the corrected engine display rotating speed. When the engine is normally working, the engine display rotating speed remains unchanged. When the engine intake temperature exceeds the engine intake temperature capability range, the engine display rotating speed gradually decreases. The corrected engine display rotating speed is convenient for pilots to remember the warming rotating speed and the upper limit of the rotating speed in the full envelope, and the operation burden is small.

Description

Technical Field

[0001] This application belongs to the field of aero-engine design, and specifically relates to a method for correcting the displayed speed of an aero-gas turbine engine. Background Technology

[0002] Currently, the engine speed displayed in the aircraft cockpit is typically the high-pressure relative physical speed n2. This parameter characterizes the engine's mechanical load, and exceeding the specified upper limit of n2 may cause mechanical damage to the engine. During flight monitoring and ground warm-up operations, the corresponding n2 speed varies at different intake air temperatures, making it difficult for pilots to remember. Furthermore, there is no direct correlation between n2 speed and engine thrust; at the same n2, engine thrust will differ during aircraft cruise or carrier landings at different intake air temperatures, which is detrimental to pilot control.

[0003] When pilots are operating an aircraft, in addition to monitoring engine parameters, they also need to monitor a large number of aircraft parameters. The engine speed displayed in the cockpit should ideally be easy for pilots to remember while also reflecting the engine's actual thrust status.

[0004] Therefore, how to accurately determine the current aircraft status while reducing the pilot's operational burden is a problem that needs to be solved. Summary of the Invention

[0005] The purpose of this application is to provide a method for correcting the displayed speed of an aviation gas turbine engine, in order to solve the problem in the prior art that the high pressure relative physical speed n2 changes continuously with different intake air temperatures, making it difficult for pilots to know the current engine status based on the high pressure relative physical speed n2, and resulting in a heavy operational burden on pilots.

[0006] The technical solution of this application is: a method for correcting the displayed speed of an aero gas turbine engine, comprising:

[0007] Based on the current engine intake air temperature T1 and the high-pressure relative physical speed control plan f n2 (T1) The control plan value n of the high pressure relative physical speed n2 at the current engine intake air temperature is obtained by linear interpolation. 2max ;

[0008] The control plan value n of the high pressure relative to the physical speed n2 2max Converted to high-pressure relative conversion speed control plan value n 2rmax ,

[0009] Calculate the current engine intake air temperature and the actual high-pressure relative physical speed n2; calculate the high-pressure relative converted speed n. 2r ,

[0010] Set the correction speed segmentation factor f kn2r (T1), obtain the speed segmentation coefficient f kn2r The relationship curve between (T1) and engine intake air temperature T1 is used to calculate the segmented node speed n. 2r_trans n 2r_trans =n 2rmax ×f kn2r (T1);

[0011] Calculate the corrected engine speed n 2k ;

[0012] When n 2r ≤n 2r_trans When, n 2k =n 2r ;

[0013] When n 2r >n 2r_trans When, n 2k =n 2r_trans +(100-n 2r_trans ) / (n 2rmax -n 2r_trans )×(n 2r -n 2r_trans ).

[0014] Preferably, when the engine intake air temperature T1 is greater than the engine's intake air temperature capability range, the speed segmentation coefficient f is corrected. kn2r (T1) gradually decreases as temperature increases.

[0015] Preferably, when T1 ≤ 327.7 K, the corrected speed segmentation coefficient f is... kn2r (T1) takes a value of 0.9 to 1.0; when T1 > 327.7K, the speed segmentation coefficient f is corrected. kn2r (T1) takes values ​​from 0.1 to 0.9.

[0016] This application discloses a method for correcting the displayed engine speed of an aero-gas turbine engine. First, based on the current engine intake air temperature and the high-pressure relative physical speed control plan, the control plan value of the high-pressure relative physical speed at the current engine intake air temperature is obtained through linear interpolation. Then, the control plan value of the high-pressure relative physical speed is converted into a high-pressure relative converted speed control plan value. The high-pressure relative converted speed is calculated by calculating the current engine intake air temperature and the actual high-pressure relative physical speed n2. A correction speed segmentation coefficient is set, and the segment node speeds are calculated to obtain the corrected engine displayed speed. When the engine is operating normally, the engine displayed speed remains constant. As the engine intake air temperature exceeds the allowable range, the engine displayed speed gradually decreases. The corrected engine displayed speed makes it easier for the pilot to remember the warm-up speed and the upper limit of the speed within the full envelope, reducing the operational burden. Attached Figure Description

[0017] To more clearly illustrate the technical solutions provided in this application, the accompanying drawings will be briefly described below. Obviously, the drawings described below are merely some embodiments of this application.

[0018] Figure 1 This is a schematic diagram of the overall process of this application. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions in the embodiments of this application will be described in more detail below with reference to the accompanying drawings.

[0020] A method for correcting the displayed speed of an aero gas turbine engine, such as... Figure 1 As shown, it includes the following steps:

[0021] Step S100: Based on the current engine intake air temperature T1 and the high-pressure relative physical speed control plan f n2 (T1) The control plan value n of the high pressure relative physical speed n2 at the current engine intake air temperature is obtained by linear interpolation. 2max ;

[0022] As the engine intake air temperature T1 changes, the control plan value n of the high pressure relative to the physical speed n2... 2max The control plan value n for high voltage relative to physical speed n2 is constantly changing. 2max It increases continuously as the engine intake air temperature T1 increases, and decreases continuously as the engine intake air temperature T1 decreases.

[0023] Step S200, the control plan value n of the high voltage relative physical speed n2 is... 2max Converted to high-pressure relative conversion speed control plan value n 2rmax ,

[0024] From the above formula, it can be seen that when the engine intake air temperature T1 increases, the high-pressure relative converted speed control plan value n 2rmax The value keeps increasing.

[0025] Step S300: Calculate the current engine intake air temperature and the actual high-pressure relative physical speed n2; calculate the high-pressure relative converted speed n. 2r ,

[0026] The relative physical speed of high pressure changes continuously with increasing temperature. Regardless of how much the engine intake air temperature increases, the relative equivalent speed n of high pressure remains constant. 2r All of them are constant values.

[0027] Step S400: Set the correction speed segment coefficient f kn2r (T1), obtain the speed segmentation coefficient f kn2r The relationship curve between (T1) and engine intake air temperature T1 is used to calculate the segmented node speed n. 2r_trans n 2r_trans =n 2rmax ×f kn2r (T1);

[0028] When the engine intake air temperature T1 is within the engine's intake air temperature capability range, set the correction speed segment coefficient f. kn2r (T1) can remain unchanged or change within a small range with temperature variations. When the engine intake air temperature T1 exceeds the engine's intake air temperature capability range, the speed segmentation coefficient f is corrected. kn2r (T1) gradually decreases as temperature increases.

[0029] In one instance f kn2r The relationship between (T1) and T1 is shown in Table 1:

[0030] Table 1 f kn2r (T1) Relationship curve with T1

[0031] <![CDATA[T1(K)]]> <![CDATA[f kn2r (T1)]]> <![CDATA[T1(K)]]> <![CDATA[f kn2r (T1)]]> <![CDATA[T1(K)]]> <![CDATA[f kn2r (T1)]]> 223.5 0.97 271 0.97 357.1 0.8 227.4 0.97 279.1 0.97 373.1 0.7 232.2 0.97 288.2 0.97 389.9 0.6 237.8 0.97 301.7 0.97 407.5 0.5 244.3 0.97 308 0.97 426 0.4 251.7 0.97 314.2 0.97 435.5 0.3 260 0.97 327.7 0.97 515 0.2 269.1 0.97 342 0.9 - -

[0032] As can be seen from Table 1, when T1≤327.7K, the corrected speed segmentation coefficient f kn2r (T1) takes a value of 0.9 to 1.0; when T1 > 327.7K, the speed segmentation coefficient f is corrected. kn2r (T1) takes values ​​from 0.1 to 0.9.

[0033] When T1 ≤ 327.7 K, the engine is in normal condition; when T1 ≤ 327.7 K, the engine is in an overheated state. 327.7 K is only the inlet temperature capability threshold for a certain aero-gas turbine engine, and the inlet temperature capability threshold may be slightly different for different aero-gas turbine engines.

[0034] When the aero gas turbine engine operates beyond its inlet air temperature capability threshold, the segment node speed n 2r_trans It will gradually decrease as the temperature continues to increase.

[0035] Step S500: Calculate the corrected engine speed n. 2k ;

[0036] When n 2r ≤n 2r_trans When, n 2k =n 2r ;

[0037] When n 2r >n 2r_trans When, n 2k =n 2r_trans +(100-n 2r_trans ) / (n 2rmax -n 2r_trans )×(n 2r -n 2r_trans ).

[0038] By using the above formula, when the engine is within its intake air temperature capability range, that is, n 2r ≤n 2r_trans When the engine speed is displayed as a constant value, it indicates that the engine is in normal operating condition. Different constant values ​​can be set depending on the engine model. When the engine is outside its intake air temperature range, that is, when n... 2r >n 2r_trans At this time, the engine speed displayed is a variable value and will not be the same as the displayed speed when the engine is operating normally; it will increase linearly as the temperature continues to increase. Thus, the pilot only needs to observe whether the engine's displayed speed changes to determine whether the aviation gas turbine engine is in normal operating condition. Of course, this method is not limited to aviation gas turbine engines; any aviation engine that can use this method is within the scope of protection of this application.

[0039] This application first uses linear interpolation to obtain the control plan value of the high-pressure relative physical speed at the current engine intake air temperature based on the current engine intake air temperature and the high-pressure relative physical speed control plan. Then, it converts the high-pressure relative physical speed control plan value into a high-pressure relative converted speed control plan value, calculates the high-pressure relative converted speed by calculating the current engine intake air temperature and the actual high-pressure relative physical speed n2, sets a correction speed segmentation coefficient, calculates the segment node speed, and thus calculates the corrected engine display speed. When the engine is operating normally, the engine display speed remains constant; as the engine intake air temperature exceeds the intake air temperature capability range, the engine display speed gradually decreases. The revised engine speed display makes it easier for pilots to remember the warm-up speed and the upper limit of the speed within the full envelope. When warming up, pilots only need to remember a specific engine speed display value and no longer need to consider the engine intake air temperature. In the intermediate and above states, pilots only need to remember a specific engine speed display value to monitor the high pressure relative physical speed exceeding the control plan value across the entire temperature range, and no longer need to consider the engine intake air temperature. When carrier-based aircraft land and cruise, they only need to remember a certain range of engine speed display values ​​to ensure that the engine thrust is within a specific range under different atmospheric temperature conditions. Furthermore, the engine speed display has a good correspondence with the throttle lever, thereby effectively reducing the pilot's flight workload.

[0040] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A method for correcting the displayed speed of an aero gas turbine engine, characterized in that, include: Based on the current engine intake air temperature T1 and the high-pressure relative physical speed control plan f n2 (T1) The control plan value n of the high pressure relative physical speed n2 at the current engine intake air temperature is obtained by linear interpolation. 2max ; The control plan value n of the high pressure relative to the physical speed n2 2max Converted to high-pressure relative conversion speed control plan value n 2rmax n 2rmax = n 2max × ; Calculate the current engine intake air temperature and the actual high-pressure relative physical speed n2; calculate the high-pressure relative converted speed n. 2r n 2r = n2× ; Set the correction speed segmentation factor f kn2r (T1), obtain the speed segmentation coefficient f kn2r The relationship curve between (T1) and engine intake air temperature T1 is used to calculate the segmented node speed n. 2r_trans n 2r_trans =n 2rmax ×f kn2r (T1); Calculate the corrected engine speed n 2k ; When n 2r ≤n 2r_trans When, n 2k =n 2r ; When n 2r >n 2r_trans hour, .

2. The method for correcting the displayed speed of an aero-gas turbine engine as described in claim 1, characterized in that: When the engine intake air temperature T1 is greater than the engine's intake air temperature capability range, the speed segmentation coefficient f is corrected. kn2r (T1) gradually decreases as temperature increases.

3. The method for correcting the displayed speed of an aero-gas turbine engine as described in claim 2, characterized in that: When T1≤327.7K, the corrected speed segmentation coefficient f kn2r (T1) takes a value of 0.9 to 1.0; when T1 > 327.7K, the speed segmentation coefficient f is corrected. kn2r (T1) takes values ​​from 0.1 to 0.9.

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