Method for determining firing parameter values ​​for a projectile ingestion test by a blade in a static position

Abstract

Method for determining firing parameter values ​​for a projectile ingestion test by a blade in a static position. One aspect of the invention relates to a computer-implemented method for determining firing parameter values ​​for a projectile ingestion test by a blade in a static position, comprising: receiving reference values ​​for parameters characteristic of damage that the blade would sustain during a reference projectile ingestion test by the blade, when said blade is rotating; and determining the firing parameter values ​​for which values ​​of parameters characteristic of damage to the blade upon impact by the projectile fired at the blade according to said firing parameter values ​​when said blade is in a static position correspond to the received reference values. Figure to be published with the abstract: Figure 1

Description

Description Title of the invention: Method for determining the values ​​of firing parameters of a test involving the ingestion of a projectile by a blade in static position TECHNICAL FIELD OF THE INVENTION

[0001] = The technical field of the invention is that of the design of the module of fan of a turbojet engine, in particular the design of the fan blades of this module.

[0002] In particular, the invention relates to the determination of the test conditions ingestion of projectiles by a fan blade. TECHNOLOGICAL BACKGROUND OF THE INVENTION

[0003] = When designing a fan blade (or “fan blade”) intended to be integrated into an aircraft turbojet fan, it is essential to ensure that a certain number of criteria and specifications are well respected. Compliance with These requirements are classically demonstrated by ground tests.

[0004] — Among these tests, the tests of ingestion of projectiles, in particular of birds or of gelatin elements, are of particular importance. Indeed, ingestion, by the aircraft engine, bird or any other foreign body can cause damage. significant damage to one or more fan blades (or "fan blades"). A piece of squid, or even the whole squid, can detach and impact others engine components, and thus cause irreversible damage to the entire structure.

[0005] — It is therefore important to ensure that the blade, during a projectile ingestion test, has a certain mechanical strength, characterized in particular in terms of unbalance post-dawn firing. Such tests are carried out in particular as soon as modifications are brought on a dawn.

[0006] A projectile ingestion test is generally carried out on a rotating module comprising several blades in a vacuum tank, or directly during a engine test also running. A projectile (often a block of gelatin) is ejected at a predefined speed via a compressed air cannon towards the rotating module or of the engine, so as to reproduce a bird impact on an engine blade of aircraft in flight condition. After the impact of the projectile on one of the blades, the blade is studied to assess the damage caused.

[0007] — Such tests, if necessary to ensure that the blade meets certain spec- technical specifications, are nevertheless very complex to implement and very expensive. Indeed, they require having a rotating module or a motor on which several blades are mounted (to ensure that one of them is properly impacted by the projectile) — generally 4 or 5 blades, as well as a vacuum tank in which the test is carried out. In addition, it is important in such tests to carefully define the firing parameters and to properly synchronize the projectile firing with the rotation of the blade, to be sure to impact the desired blade at the right time and at the right height. The invention aims to improve the situation. Summary of the invention The invention provides a solution to the problems mentioned above, by making it possible to define firing parameters for a projectile ingestion test on a blade in a static position so as to obtain damage to the blade which is similar to damage that the blade would have suffered during a projectile ingestion test carried out on the rotating blade. By "similar", it is understood that certain characteristic parameters (considered to be the most important in relation to the technical specifications that the blade must verify during a projectile ingestion test) of the damage are reproduced. Indeed, following various studies of mechanical influences, the inventors found that by defining certain firing parameters, it is possible to reproduce in static testing (i.e. during a projectile ingestion test on a blade in static position) damage obtained in dynamic testing (i.e. during a projectile ingestion test on a rotating blade). However, it is far from clear that it is possible to reproduce damage generated on a rotating blade with a test carried out on a blade in a static position. Indeed, the stresses on the blade are not the same when it is rotating or when it is static. During a rotating test, the blade exhibits centrifugal stiffening upon impact (in ingestion) which cannot be easily reproduced during a static ingestion test. However, by redefining the firing conditions for a static ingestion test, the inventors have proven that it is possible to obtain similar composite damage to the blade in dynamic and static tests. The studies carried out were validated by a series of static tests at the end of which the damage was studied and compared to the damage expected in dynamic tests. One aspect of the invention thus relates to a computer-implemented method for determining values ​​of firing parameters of a test of ingestion of a projectile by a blade in a static position. In one or more embodiments, this method may comprise: receive reference values ​​of parameters characteristic of a damage- magement that dawn would undergo during a reference ingestion test of projectile by the blade, when said blade is rotating; and determine the values ​​of the shooting parameters for which values ​​of the characteristic parameters of blade damage during impact by the projectile fired at the dawn according to the said values ​​of the firing parameters when said blade is in static position correspond to the values ​​of reference received. As known to those skilled in the art, a “projectile ingestion test” refers to a test in which a projectile (e.g., a volume of gelatin) is sent onto a blade in order to assess the behavior of the blade upon impact—in particular, the damage caused to the blade. Conventionally, projectile ingestion tests are carried out on a blade rotating about an axis (i.e., a blade driven by a motor). The invention specifically aims to overcome the rotation constraint, to replace a projectile ingestion test on a rotating blade (in rotation) with a projectile ingestion test on a fixed blade (in a static position). "Firing parameters" means a set of parameters under which the projectile is launched towards the blade during the projectile ingestion test. "Reference projectile ingestion test" means a test carried out on a rotating blade whose conditions (including, in particular, the firing parameters) are predefined to meet a set of specifications. By "characteristic parameters of damage" is meant a set of parameters describing the damage suffered by the blade during a test (on a static or rotating blade). These characteristic parameters make it possible to describe the main properties of the damage caused to the blade. For the purposes of the invention, there may be a single characteristic parameter, at least one characteristic parameter, or at least two characteristic parameters. The "reference values ​​of characteristic parameters" represent the values ​​of these characteristic parameters for a reference projectile ingestion test. They are generally determined from "real" tests implemented in the past. According to advantageous embodiments, these values ​​are known and no projectile ingestion test on a rotating blade is necessary to implement within the scope of the present invention. Thus, the present invention advantageously aims to define a set of firing parameters for a so-called "static" test (i.e. a projectile ingestion test on a blade in a static position) for which the damage to the blade is similar to that which would be obtained if the test had been carried out dynamically (i.e. on a rotating blade). Indeed, the inventors have determined, using numerous si- mulations, that by redefining the values ​​of firing parameters in relation to the reference values ​​of the static test, it was possible to reproduce at least partially the damage that the blade would have suffered during the dynamic test. By "at least partially", it is understood that characteristics determined as being essential in the evaluation of the behavior of the blade in reaction to a projectile impact are sufficiently close (according to predefined adequacy conditions). For example, a condition of adequacy between damage in dynamic firing and damage in static firing may be based on a maximum permissible difference between the two damage dimensions.For example, damages may be considered similar if their directions relative to a reference axis do not differ by more than x degrees (x being a real number, e.g. 5 or 10 degrees) and / or if the length of one of the damages is less than a predefined percentage of the length of the other damage (e.g. 15%, 20% or 30% of the length of the other damage). The invention therefore makes it possible to avoid, at least in the initial testing phases, numerous projectile ingestion tests on rotating blades, which are complex to implement and very costly, by replacing them with static tests, which are less costly and simpler to carry out. In one or more embodiments, determining the values ​​of the firing parameters may include: receive first values ​​of the shooting parameters; simulate damage to the blade upon impact by the fired projectile on the dawn according to said first values ​​of the firing parameters when said dawn is in static position; determine values ​​of the characteristic parameters of damage simulated; and compare the values ​​of the characteristic parameters of the damage simulated with the received reference values. Furthermore, as long as the values ​​of the simulated damage characteristic parameters do not correspond to the received reference values, the simulation of the blade damage and the determination of the values ​​of the simulated damage characteristic parameters can be repeated with new values ​​of the firing parameters. According to these embodiments, the values ​​of the firing parameters of the static test are determined by successive simulations of the behavior of the blade during an impact by a projectile with several sets of firing parameter values, until determining those which provide damage similar to that sought (i.e. that caused by the reference projectile ingestion test). In one or more embodiments, the firing parameters may include at least one of: a parameter representative of a firing height, a parameter representative of a projectile launch velocity, a parameter representative of a projectile mass, and a parameter representative of a projectile firing incidence angle. In fact, the inventors have determined during numerous experiments that these four parameters have a particular influence on the damage suffered by the blade. Additionally, the projectile ingestion reference test may be associated with predefined conditions including: a reference firing velocity, a reference firing height, and a reference projectile mass. In one or more embodiments, the characteristic parameters of damage may comprise at least one of: a type of damage, a parameter for locating the damage on the blade, a parameter for sizing the damage, a parameter for directing the damage relative to an axis of the blade. The type of damage may for example be a tear, a bend, a crack, a debonding, an indentation, a scratch, etc. The damage location parameter may correspond to a position of the damage on the blade, for example "damage at the blade tip", "damage at the blade root", or "damage between a height H and a height H' relative to the blade root", etc. The damage sizing parameter may correspond to a size of the damage, and the damage direction parameter may be a direction class, for example "radial damage", or an angle of the damage direction relative to a reference axis of the blade, for example "damage at an angle to relative to the axis of the blade root". The above list of examples is provided for illustrative purposes and is not intended to be limiting. Of course, other characteristic parameters can be defined, depending on the tests carried out on the blade and the specifications considered. Another aspect of the invention relates to a system for determining values ​​of firing parameters of a test of ingestion of a projectile by a blade in a static position. This system may comprise: an input interface for receiving parameter reference values characteristics of damage that the blade would suffer during a test of reference to projectile ingestion by the blade, when said blade is in rotation; and a calculator to determine the values ​​of the shooting parameters for which of the values ​​of the characteristic parameters of damage of the dawn upon impact by the projectile fired at the dawn according to said values ​​of the firing parameters when said blade is in static position cor- correspond to the received reference values. Another aspect of the invention relates to a method of testing the ingestion of a projectile by a blade in a static position. In one or more embodiments, this method may comprise: determine the values ​​of firing parameters of the projectile ingestion test by the blade in static position according to one of the preceding methods; and launch the projectile on the dawn in static position according to the values ​​of the pa- determined shooting ranges. According to this method, a static test is advantageously implemented and reproduces, at least partially, the damage which would have been obtained with a dynamic test. Another aspect of the invention relates to a system for testing the ingestion of a projectile by a blade in a static position, which may comprise: a system for determining values ​​of test firing parameters ingestion of the projectile by the blade in static position; and a cannon to launch the projectile on the dawn in static position according to the determined values ​​of the firing parameters. A computer program, implementing all or part of the process described above, installed on pre-existing equipment, is in itself advantageous. Thus, the present invention also relates to a computer program comprising instructions for implementing certain steps of the method described above, when this program is executed by a processor. This program may use any programming language (e.g., an object-oriented language or otherwise), and may be in the form of interpretable source code, partially compiled code, or fully compiled code. The [Fig.1] described in detail below can form the flowchart of the general algorithm of such a computer program. The invention and its various applications will be better understood by reading the following description and examining the accompanying figures. BRIEF DESCRIPTION OF THE FIGURES Other features and advantages of the invention will become apparent upon reading the description, which may be read in conjunction with the figures. These figures are presented for information purposes only and in no way limit the invention. [Fig.1] [Fig.1] represents a flowchart of a method for determining the values ​​of the firing parameters for a projectile ingestion test on a blade in a static position, according to one or more embodiments of the invention. [Fig.2] [Fig.2] represents a flowchart of a method for testing the ingestion of a projectile by a blade in a static position, according to one or more embodiments of the invention. [Fig.3a], [Fig.3b] Figures 3a and 3b represent several views of a blade during a test of ingestion of a projectile in a static position, according to one or more embodiments of the invention. [Fig.4] [Fig.4] represents a device for determining the values ​​of the firing parameters for a projectile ingestion test on a blade in a static position, according to one or more embodiments of the invention. DETAILED DESCRIPTION [Fig.1] [Fig.1] represents a flowchart of a method for determining the values ​​of the firing parameters for a projectile ingestion test on a blade in a static position, according to one or more embodiments of the invention. In a step 110, reference values ​​of parameters characteristic of the damage that the blade would undergo during a test of ingestion of a reference projectile by the rotating blade are received. These parameter values ​​make it possible to characterize the damage that the blade would undergo if it were subjected to a “dynamic” test (i.e. on a rotating blade) of ingestion of a reference projectile. They are generally known from experience, from dynamic tests implemented in the past. It is noted that no such dynamic test is implemented in the method described here, which aims precisely to replace a dynamic test with a static test (i.e. on a blade in a static position). Dynamic tests are performed under predefined and standardized conditions, which depend in particular on the type of test and the characteristics of the blade. For example, the test type is generally one of "small bird", "medium bird" or "large bird", and represents the size category of bird for which the impact on the blade is to be studied. For each type of test, the mass of the projectile is calculated based on the air inlet area of ​​the engine (or inlet surface). For example, the European Aviation Safety Agency (EASA) defines conditions for conducting ingestion tests based on the air inlet surface of the engine. For an area between 1.35 m? and 3.90 m°, the “medium bird” type ingestion is carried out with a projectile of at least 2.5 pounds (approximately 1.15 kg). The predefined conditions of the dynamic ingestion test can therefore include the mass of the projectile, or any equivalent value (for example the height and diameter of the projectile, if it is of known shape and density), as well as the launch velocity of the projectile (i.e. the speed at which the projectile is launched by the gun towards the blade) or the firing height (i.e. the height at which the projectile is launched relative to the base of the blade). These quantities are described below with reference to [Fig.3a] in the case of a static ingestion test (their definitions remain the same in dynamic and static). Upon impact of the projectile with the blade, the latter suffers damage, which can be characterized by several parameters. For example, the damage suffered by the blade can be of a particular type among a plurality of possible types, such as a tear, a bend, a crack, etc.This damage may also be characterized by a location parameter at the blade (e.g., "tip damage," or "damage between X% and Y% of the blade height," where X% and Y% are percentages of the blade height relative to the blade root), by one or more dimension parameters (e.g., a length and / or thickness of the damage), or by a parameter relating to a direction of the damage relative to a blade axis (e.g., an angle of a tear relative to the blade root axis or relative to an axis extending from the center of the blade root to the center of the blade tip, or a direction category such as "radial"). For example, in a "medium bird" dynamic ingestion test, the damage may be a tear or crack, at least 1 mm long.This type of damage is caused by the impact of the projectile which, upon contact with the part and its intrinsic inertia, damages the composite at the leading edge of the blade. Referring again to [Fig. 1], during step 110, these are therefore the parameters characteristic of the damage expected for a projectile ingestion test under predefined conditions, called “reference projectile ingestion test” which are received. During a step 120, static firing parameter values ​​are determined. By "static firing parameters" is meant firing parameters associated with a test of projectile ingestion by the blade when the latter is in a static position (static ingestion test). In step 120, the values ​​of the static firing parameters determined are the values ​​for which the values ​​of the characteristic parameters of the damage to the blade obtained during the static ingestion test are substantially the same (i.e. the same or sufficiently close) as the values ​​of the characteristic parameters of the damage to the blade obtained during the dynamic reference ingestion test, i.e. the values ​​of the characteristic parameters received in step 110. In other words, in step 120, the values ​​of the static firing parameters determined are the values ​​for which the damage to the blade obtained during the static ingestion test carried out with these firing parameter values ​​is similar to the damage that the blade would have suffered during the reference dynamic projectile ingestion test. Through their research, the inventors identified that by choosing the appropriate values ​​of certain firing parameters, it is indeed possible to reproduce in static form damage similar to that which would have been obtained during a dynamic test. The parameters identified as being the most important (i.e. having the greatest influence on the damage caused) include: the mass of the projectile, the projectile launch velocity, the firing height and the firing angle of incidence (defined here as the angle between a perpendicular to the firing direction and the direction of the blade root axis, as detailed below with reference to [Fig.3b]). It is noted that in dynamic testing, the angle of incidence is not one of the firing parameters whose value can vary; the projectile is launched in the direction of the motor axis.It is also noted that, while the projectile mass, the projectile launch velocity, and the firing height are also part of the firing parameters of the reference dynamic test, their values ​​are not necessarily the same as the values ​​determined in step 120. In other words, to reproduce damage obtained during a reference dynamic test having reference firing conditions, it may be necessary to modify certain values ​​of firing parameters of the static test, such as the projectile mass or the projectile launch velocity. In one or more embodiments, step 120 may comprise steps 121, 122, 123 and 124 detailed below. In a step 121, first firing parameter values ​​are received. Step 122 comprises a simulation of the damage that the blade would undergo during a projectile ingestion test with the first firing parameter values ​​received in step 121, when the blade is in a static position. In a particular embodiment, this step 122 can be carried out using simulation software, for example LS-Dyna. Then, values ​​of the characteristic parameters of the simulated damage are determined in step 123. In step 124, the so-called “static” values ​​determined in step 123 are compared with the so-called “dynamic” values ​​received in step 120. If the static values ​​differ from the dynamic values ​​(i.e. if the values ​​differ for at least one characteristic parameter), new firing parameter values ​​(i.e.a new set of firing parameter values ​​at least one of which has a different value from the previous set of firing parameter values) are received, which means that step 121 is repeated with new ones. shooting parameter values. Steps 122, 123 and 124 are then repeated with these new values. If during step 124 the static values ​​are equal to the dynamic values, then the values ​​125 of the firing parameters are retained and constitute the output data of step 120. It is noted that the values ​​of the characteristic parameters of damage can designate categories, point values, but also ranges of values. For example, in one embodiment, the characteristic parameters of the damage can comprise a length of the damage. The reference value of the damage length in dynamic testing can be for example the range of values ​​[50 - 250] mm. In step 123, it can be determined for example that the length of the simulated damage in static testing is 30 mm, and in step 124 it is looked at whether the value 30 mm belongs or not to the interval [50 - 250] mm, which is not the case and therefore step 121 is repeated with new values ​​of the set of shooting parameters. It is noted that the damage obtained during the static blade projectile ingestion test may not be strictly equivalent to the damage that would be obtained during a reference rotating blade projectile ingestion test (if only because this damage is subject to variability from one test to another). The characteristic damage parameters therefore cover here the parameters for which it is fundamental to obtain identical or similar values ​​in static and dynamic conditions in order to be able to replace the dynamic test with the static test. [Fig.2] represents a flowchart of a method for testing the ingestion of a projectile by a blade in a static position, according to one or more embodiments of the invention. In a step 210, reference conditions associated with a reference projectile ingestion test on a rotating blade are received. As mentioned previously, these conditions are predefined from standards and specifications for obtaining certification of the blade. For example, according to certain embodiments, these reference conditions include the mass of the projectile, the launch velocity of the projectile and the firing height of the projectile. Of course, in other embodiments, the reference conditions may include other parameters or parameters different from those defined previously. Then, reference values ​​of the characteristic parameters of the damage that the blade would undergo during a test of ingestion of a reference projectile by the rotating blade under the conditions received in step 210 are received in a step 220. These reference values ​​of the characteristic parameters are defined in a similar manner to step 110 of [Fig. 1]. These values ​​can be determined from the conditions received in step 210, using data from previous dynamic tests carried out under the same conditions. It is recalled that in step 220, no dynamic test is actually carried out. The values ​​of the firing parameters for which the values ​​of the parameters characteristic of damage to the blade during an impact by the projectile fired on the blade according to said values ​​of the firing parameters when said blade is in a static position correspond to the reference values ​​received in step 220 are determined during a step 120 similar to that of [Fig.1]. Finally, during a step 220, a projectile ingestion test can be carried out on the blade in a static position, with the firing parameters determined during the previous step 120. This step 220 can be carried out to validate that the damage obtained was indeed consistent with the desired damage (i.e. consistent with the damage that was expected to be obtained if the ingestion test had been carried out on a rotating blade), and therefore validate that the method of [Fig. 1] is indeed operational. This step 220 can also be implemented as part of the tests carried out on the blade for the purpose of certification. Figures 3a and 3b represent several views of a blade during a test of ingestion of a projectile in a static position, according to one or more embodiments of the invention. [Fig. 3a] represents a fan blade 301 comprising in particular a leading edge 302 and a trailing edge 303. The fan blade is typically intended to be fixed on a fan disk of a turbomachine fan, with a plurality of other blades. In the context of a projectile ingestion test in a static position, the blade 301 can be connected to a static support 304. In the embodiment of [Fig. 3a], the blade 301 is connected to the support 304 via its root, so that the blade extends generally in a plane perpendicular to the support (the root of the blade is oriented along the Z axis and the blade extends substantially along the X axis). Of course, other configurations are possible. A gun 305 is positioned facing the blade 301, in the plane (XZ) at a predetermined distance therefrom. The gun 305 is intended to launch a projectile 306 towards the blade 301, so that the projectile 306 comes into contact with the blade on the intrados face thereof. The projectile 306 may be, for example, a predetermined volume (for example, a cylinder) made of gelatin or another material, or any other object intended to reproduce as faithfully as possible an impact of a live bird on an engine in flight. The firing parameters may be determined according to the method described with reference to Figure 1, and may in particular include: the mass of the projectile 306, the firing speed of the projectile, the firing height λ and the firing angle of incidence λ. Of course, these parameters can be replaced by other characteristic parameters of equivalent or proportional magnitudes. For example, the mass of the projectile 306 can be replaced by one or more dimensions of the projectile when the latter is a predefined volume made of a material of known volume density (for example, when the projectile is cylindrical in shape with a predefined diameter, the mass of the projectile 306 can be replaced by the height of the cylinder). As for a projectile ingestion test by a rotating blade, the mass of the projectile is a function of the height of the blade considered. It is recalled that the mass of the projectile determined during the method according to [Fig. 1], ie. the mass of the projectile 306 used for a projectile ingestion test on a blade in a static position can be different from the mass of the projectile of the projectile ingestion test on an “equivalent” rotating blade (iethe reference dynamic ingestion test, in which we seek to reproduce the damage to the blade). The firing speed (or launch speed) of the projectile 306 corresponds to the ejection speed by the barrel 305 of the projectile 306 in the firing direction. It is recalled that the firing speed of the projectile determined during the method according to [Fig.1], i.e. the speed used for an ingestion test of the projectile 306 on the blade in a static position, may be different from the firing speed of the projectile in the “equivalent” rotating projectile ingestion test on the blade (i.e. the reference dynamic ingestion test, for which the damage to the blade is to be reproduced). The firing height Δ (or launch height) corresponds to the height of the center of the projectile 306 or the center of the gun 305, and therefore to the height at which the projectile 306 is launched towards the blade 301. This height / can be expressed as a distance from the ground or any other reference point (for example the base of the foot of the blade, the center of the support, etc.), or as a relative height, for example relative to the height H of the blade 301. For example, the firing height h can be expressed as a percentage or fraction of the total height H of the blade (for example 0.80 x ) and represent the height of the center of the projectile 306 or the gun 305 relative to the foot of the blade 301. Here again it is recalled that the firing height of the projectile determined during the method according to Figure 1, i.e.the firing height firing height A used for a projectile ingestion test on a blade in a static position may be different from the projectile firing height of the projectile ingestion test on a rotating blade "equivalent" (i.e. the reference dynamic ingestion test, for which the damage on the blade is to be reproduced). The firing angle of incidence (or launch angle of incidence) is shown in Figure 3b, which illustrates a top view of the system of Figure 3a. The firing angle of incidence ! corresponds to the angle between a direction perpendicular to the firing direction of the projectile 306 (in Figure 3b, the firing direction is along the axis longitudinal axis of the gun 305, which represents the direction of the "firing speed" of the projectile 306) and the axis along which the root of the blade 301 extends. It is recalled that during a projectile ingestion test by a rotating blade (dynamic ingestion test), the projectile is generally launched in the direction of the engine axis (i.e., in Figures 3a and 3b, in the Oy direction). During a projectile ingestion test by a blade in a static position (static ingestion test), it is necessary to determine this angle of incidence / to compensate for the absence of rotation of the blade and thus reproduce the damage that would be obtained in a dynamic ingestion test. [Fig.4] represents a device for determining the values ​​of the firing parameters for a projectile ingestion test on a blade in a static position, according to one or more embodiments of the invention. In these embodiments, the device comprises a computer 400, comprising a memory 401 for storing instructions allowing the implementation of the method, the reference values ​​of the characteristic parameters of the damage in rotating test received, and temporary data for carrying out different steps of the methods described previously. The computer 400 further comprises a circuit 402. This circuit may be, for example, a processor capable of interpreting instructions in the form of a computer program, an electronic card whose steps of the method of the invention are described in the silicon, or even a programmable electronic chip such as an FPGA chip (for “Field-Programmable Gate Array” in English). The computer 400 comprises an input interface 403 for receiving reference values ​​of the characteristic parameters of the damage in a rotating test and / or predefined conditions associated with a test of ingestion of a reference projectile by the rotating blade, and an output interface 404 for providing the values ​​of the firing parameters for which the damage to the blade during a projectile ingestion test on the blade in a static position is similar to that during a projectile ingestion test on the rotating blade. Finally, the computer may comprise, to allow easy interaction with a user, a screen 405 and a keyboard 406. Of course, the keyboard is optional, in particular in the context of a computer having the form of a touch pad, for example. Furthermore, the functional diagram presented in [Fig. 1] is a typical example of a program, some of whose instructions can be carried out using the device described. As such, [Fig. 1] may correspond to the flowchart of the general algorithm of a computer program within the meaning of the invention. Of course, the present invention is not limited to the embodiments described above as examples; it extends to other variants. For example, if the invention is described here in the context of a turbojet blade, it can be extended to any type of blade, and even to any mechanical part on rotating tests generally carried out.

Claims

Claims

1. A computer-implemented method for determining values ​​of firing parameters of a test of ingestion of a projectile by a blade in static position, including: receive reference values ​​of characteristic parameters- characteristics of damage that the blade would suffer during a reference test of projectile ingestion by the blade, when said blade is rotating; and determine the values ​​of the shooting parameters for which values ​​of the characteristic parameters of damage of the dawn upon impact by the projectile fired at the dawn according to said values ​​of the firing parameters when said blade is in static position correspond to the reference values RECEIVED.

2. A method according to claim |, wherein determining the shooting parameter values ​​include: receive first values ​​of the shooting parameters; simulate blade damage upon impact by the projectile fired at dawn according to the said first values ​​of the firing parameters when said blade is in static position; determine the values ​​of the characteristic parameters of simulated damage; and compare the values ​​of the characteristic parameters of the simulated damage with the received reference values.

3. The method of claim 2, wherein, as long as the values ​​of the characteristic parameters of the simulated damage do not cor- do not correspond to the received reference values, the simulation of damage to the aubc and the determination of the values ​​of the pa- characteristic parameters of the simulated damage are reiterated with new values ​​of shooting parameters.

4. Method according to one of the preceding claims, in which the pa- shooting meters include at least one parameter from: a representative parameter of a shooting height, a representative parameter of a projectile launch speed, a representative parameter of a mass of the projectile and a parameter representative of an angle of the projectile's firing incidence.

5. A method according to any preceding claim, wherein the test projectile ingestion reference is associated with pre- defined including: a reference firing speed, a firing height reference and a projectile reference mass.

6. Method according to one of the preceding claims, in which the pa- characteristic parameters of damage include at least one of: a damage type, a location parameter of damage to the blade, a sizing parameter of damage, a damage direction parameter by relative to a blade axis.

7. System for determining values ​​of firing parameters of a test ingestion of a projectile by a blade in a static position, including: an input interface for receiving reference values of characteristic parameters of damage that would experience dawn during a reference ingestion test of projectile by the blade, when said blade is rotating; and a calculator to determine the values ​​of the parameters of shooting for which values ​​of the characteristic parameters of damage to the blade during an impact by the projectile fired at dawn according to said parameter values firing when said blade is in static position correspond to the received reference values.

8. Method of testing ingestion of a projectile by a blade in position static, the method comprising: determine test firing parameter values ingestion of the projectile by the blade in static position by the method according to one of claims 1 to 6; and launch the projectile on the dawn in a static position according to the determined values ​​of the firing parameters.

9. System for testing the ingestion of a projectile by a blade in position static, including: a system according to claim 7 for determining firing parameter values ​​of the projectile ingestion test by the dawn in static position; and a cannon to launch the projectile onto the dawn in position static according to the determined shooting parameter values.

10. Computer program product comprising instructions for implement certain steps of the process according to one of the res- indications 1 to 6 and 8 when this program is executed by a processor.