SYSTEM FOR SAMPLING AND ANALYSIS OF CONTRAILS GENERATED BY AN AIRCRAFT

Description

TECHNICAL FIELD

[0001] The present invention relates to the analysis of condensation trails generated by an aircraft. In particular, it relates to the analysis and sampling of condensation trails generated by an aircraft. STATE OF THE ART

[0002] Measuring emissions generated by aircraft jet engines in flight is important for understanding the contribution of these emissions to Earth's climate change. This will be necessary for the study of new-generation fuels, such as biofuels or hydrogen. In particular, understanding the contribution of condensation trails to Earth's climate change is also important.

[0003] For contrail analysis, one could consider using a second aircraft equipped with collection probes that collect air and ice crystal samples from contrails generated by a preceding aircraft. However, placing an aircraft in the jet stream of a preceding aircraft may be inefficient and expensive due to the use of the second aircraft. Such an example can be found in A. Petzold: "Near-field measurements on contrail properties from fuels with different sulfur content", December 31, 1997 (1997-12-31), pages 29867-59880. STATEMENT OF THE INVENTION

[0004] The present invention aims to overcome these drawbacks by proposing a system and a method for sampling and analyzing condensation trails.

[0005] To this end, the invention relates to a system for sampling and analyzing condensation trails generated by at least one engine of an aircraft in flight. According to the invention, the system is configured to be carried on board the aircraft and comprises at least: a collection probe configured to collect samples of the condensation trail generated by said engine of said aircraft in flight; a fixing device, the collection probe being configured to be fixed to the aircraft by the fixing device, the fixing device comprising: a support configured to be fixed to the fuselage of the aircraft and a displacement module fixed to the support, wherein the displacement module is configured to move the collection probe relative to the aircraft to a position in which the collection probe is located in the condensation trail; a collection chamber configured to collect the samples collected by the collection probe; a collection tube configured to conduct the samples from the collection probe to the collection chamber;at least one first measuring device configured to measure at least one parameter characterizing the samples in the collection tube while said samples are conducted from the collection probe to the collection chamber.;

[0006] Thus, thanks to the system configured to be carried on board the aircraft, it is not necessary to use a second aircraft behind the first aircraft in order to collect samples of the condensation trails generated by the first aircraft.

[0007] Additionally, the system includes a vacuum pump configured to drive samples from the collection probe to the collection chamber.

[0008] Additionally, the system includes a temperature control device configured to maintain the interior of the collection tube at a desired operating temperature.

[0009] Furthermore, the temperature control device comprises an insulating tube at least partially enveloping the collection tube, the insulating tube being configured to circulate a refrigerant or a mixture of refrigerant and air between the collection tube and the insulating tube.

[0010] In addition, the or each of the first measuring devices comprises a first measuring unit configured to determine at least one parameter characteristic of a chemical composition of the samples.

[0011] Furthermore, the or each of the first measuring devices comprises a second measuring unit configured to determine at least one characteristic parameter of a particle size distribution of particles contained in the samples.

[0012] Advantageously, the collection chamber is configured to be maintained at a storage temperature for the samples collected in the collection chamber.

[0013] Furthermore, the system comprises at least one second measuring device configured to measure at least one characteristic parameter of the samples collected in the collection chamber.

[0014] In addition, the or each of the second measuring devices comprises a third measuring unit configured to determine a characteristic parameter of a chemical composition of the samples.

[0015] Furthermore, the or each of the second measuring devices comprises a fourth measuring unit configured to determine a characteristic parameter of optical properties of the samples.

[0016] According to a first embodiment, the displacement module comprises a retractable rod having a first end to which the collection probe is attached, the retractable rod being configured to alternately take at least a first configuration in which the retractable rod is deployed to bring the collection probe into a first position in which the collection probe is located in the condensation trail and a second configuration in which the retractable rod is retracted to move the collection probe away from the condensation trail in a second position.

[0017] According to a second embodiment, the movement module comprises an articulated rod, the articulated rod having a first end comprising a joint attached to the support and a second end to which the collection probe is attached, the joint being configured to move the collection probe alternately at least between a third position in which the collection probe is located in the condensation trail and a fourth position in which the collection probe is spaced from the condensation trail.

[0018] The invention also relates to a method of using the condensation trail sampling and analysis system generated by at least one engine of an aircraft in flight such as that described above.

[0019] According to the invention, the method comprises the following steps: a step of collecting, by the collection probe, samples of the condensation trail generated by said reactor of said aircraft in flight; a step of conducting, by the collection tube, the samples collected by the collection probe to the collection chamber; at least one step of measuring by the first measuring device(s) at least one characteristic parameter of the samples in the collection tube while they are conducted from the collection probe to the collection chamber; a step of collecting in the collection chamber the samples collected by the collection probe and conducted by the collection tube.

[0020] The invention also relates to an aircraft, in particular a transport aircraft, comprising a sampling and analysis system such as that specified above. BRIEF DESCRIPTION OF THE FIGURES

[0021] The invention, with its characteristics and advantages, will emerge more clearly on reading the description given with reference to the appended drawings in which: There figure 1 represents a top view of an aircraft in flight generating condensation trails and carrying a sampling and analysis system. The figure 2 represents a perspective view of an aircraft in flight carrying a sampling and analysis system according to one embodiment. The figure 3 represents a perspective view of an aircraft in flight carrying a sampling and analysis system according to another embodiment. The figure 4 represents a front view of an aircraft carrying a sampling and analysis system whose collection probe is placed in the condensation trail. The figure 5 represents a side view of an aircraft carrying a sampling and analysis system whose collection probe is placed in the condensation trail. The figure 6 schematically represents the process of using the sampling and analysis system. DETAILED DESCRIPTION

[0022] There figure 1 represents the system 1 for sampling and analyzing condensation trail 5 generated by at least one reactor 13 of an aircraft AC in flight. In the remainder of the description, the sampling and analysis system is called “system 1”.

[0023] The system, configured to be carried on the aircraft AC, comprises a collection probe 2 configured to be fixed on the aircraft AC by a fixing device 3. The collection probe is also capable of collecting samples 4 of the condensation trail 5. In the figure 1 , samples 4 are represented schematically by an arrow indicating their direction of movement relative to the aircraft AC.

[0024] Generally, the samples 4 of the contrail 5 contain elements of the contrail 5. Thus, the samples include at least one of the following elements: ice crystals, unburned fuel residues (HC), oxygen (O 2 ), ozone (O 3 ), carbon monoxide (CO), carbon dioxide (CO 2 ), nitrogen oxides (NO x ).

[0025] Advantageously, the collection probe 2 comprises a valve making it possible to prevent or authorize the collection of the samples 4.

[0026] The system 1 therefore makes it possible to take samples 4 directly in the condensation trail 5. In fact, the collection probe 2 can be arranged directly in the condensation trail 5 generated by the reactor of the aircraft on which said system 1 is integrated.

[0027] The system 1 also includes a collection chamber 6 configured to collect the samples 4 collected by the collection probe 2 and a collection tube 7 (shown as a dotted line on the figure 1 ) configured to conduct samples 4 from collection probe 2 to collection chamber 6.

[0028] The system 1 can be installed on board the aircraft AC in the following manner. The collection probe 2 is configured to be attached to the aircraft AC on a portion of the fuselage of the aircraft AC at the rear of the engine(s) 13 of the aircraft AC in the direction of movement of the aircraft AC. The collection tube 7 is configured to be installed parallel to a longitudinal axis 14 of the aircraft AC on board the aircraft AC. The collection chamber 6 is configured to be installed in a portion of the aircraft AC at the front of the engine(s) 13.

[0029] In a non-limiting manner, the collection tube 7 may have a length between a length substantially equal to half the length of the aircraft AC and a length substantially equal to a third of the length of the aircraft AC.

[0030] The length of the collection tube 7 makes it possible to observe the evolution of the samples 4, in particular of the ice crystals, in time and distance, as if the measurements of the parameters were carried out in an area behind the aircraft AC in which the condensation trail 5 is completely formed and in which the ice crystals contained in the samples 4 have their final size and their final chemical composition.

[0031] Furthermore, by knowing the type of fuel consumed by the aircraft AC in flight and the flight conditions, it is possible to measure the gradual formation of ice crystals in the condensation trail 5 as a function of the type of fuel and the flight conditions.

[0032] In order to drive the samples 4 in the collection tube 7 from the collection probe 2 to the collection chamber 6, the system 1 may comprise a vacuum pump 9. The vacuum pump 9 makes it possible to create a vacuum in the collection tube 7 in order to suck the samples 4 through the collection probe 2 and drive them into the collection chamber 6 by suction. Furthermore, the system 1 may comprise a flow regulator configured to regulate the flow rate of the samples 4 in the collection tube 7 sucked by the vacuum pump 9. According to a particular example, the vacuum pump 9 may act as a flow regulator by regulating the pumping rate of the vacuum pump 9.

[0033] The system 1 further has at least one measuring device 8 configured to measure at least one parameter characterizing the samples 4 in the collection tube 7 while they are conducted from the collection probe 2 to the collection chamber 6.

[0034] The system 1 may comprise a plurality of measuring devices 8 distributed along the collection tube 7. The figure 1 shows an example of the system 1 having three measuring devices 8 including a measuring device 8 arranged in the vicinity of the collection probe 2, a measuring device arranged in the vicinity of the collection chamber 6 and a measuring device 8 arranged substantially in the middle of the collection tube 7.

[0035] The or each of the measuring devices 8 may comprise a measuring unit 81 configured to determine at least one characteristic parameter of a chemical composition of the samples 4. The measuring unit 81 may contain a spectrometer.

[0036] The or each of the measuring devices 8 may further comprise a measuring unit 82 configured to determine at least one characteristic parameter of a particle size distribution, such as ice crystals, contained in the samples 4. The measuring unit 82 may contain a particle size sensor 82.

[0037] Thus, the spectrometer 81 makes it possible to analyze the chemical composition of the samples 4. The particle size sensor 82 makes it possible to count the particles contained in the samples 4 and to determine the size of these particles.

[0038] Furthermore, by knowing the type of fuel consumed by the AC aircraft in flight and the flight conditions, it is possible to measure the concentration of particles 4 as a function of the type of fuel and the flight conditions.

[0039] The system may also comprise at least one measuring device 12 configured to measure at least one characteristic parameter of the samples 4 collected in the collection chamber 6.

[0040] The or each of the measuring devices 12 may comprise a measuring unit 121 configured to determine a characteristic parameter of a chemical composition of the samples 4, in particular of the ice crystals contained in the samples 4.

[0041] The or each of the measuring devices 12 may further comprise a measuring unit 122 configured to determine a characteristic parameter of optical properties of the samples 4, in particular of the ice crystals contained in the samples 4. The optical properties determined may be the infrared absorption or the reflectivity of the samples 4.

[0042] Thus, it is possible to analyze in flight the optical properties of ice crystals generated in condensation trails 5.

[0043] The measuring unit 121 and the measuring unit 122 may each contain a spectrometer.

[0044] Advantageously, the fixing device 3 of the collection probe 2 may comprise a support 31 configured to be fixed to the fuselage of the aircraft AC and a displacement module 32 fixed to the support 31. The displacement module 32 is configured to move the collection probe 2 relative to the aircraft AC. The fixing support 3 may be formed of beams mounted in a pyramid having at least three faces. For example, the base of the pyramid is fixed to the fuselage and the displacement module 32 is fixed to the top of the pyramid.

[0045] According to a first embodiment ( figure 2 ), the displacement module 32 comprises a retractable rod 33 having a first end to which the collection probe 2 is fixed and a second end fixed to the support 31. The retractable rod 33 is configured to alternately take at least one configuration in which the retractable rod 33 is deployed to bring the collection probe 2 into a position C1 in which the collection probe 2 is located in the condensation trail 5 and a configuration in which the retractable rod 33 is retracted to move the collection probe 2 away from the condensation trail 5 into a position C2. figure 2 represents the two positions C1 and C2 of the collection probe 2. In position C1 of the collection probe 2, the retractable rod 33 is in the configuration in which it is deployed, whereas, in position C2 of the collection probe 2, the retractable rod 33 is in the configuration in which it is retracted. On the figure 3 , the double arrow 36 indicates the transition from position C1 to position C2 and vice versa.

[0046] According to a second embodiment ( figure 3 ), the movement module 32 comprises an articulated rod 35. The articulated rod 35 has a first end comprising a joint 34 fixed to the support 31. The articulated rod 35 has a second end to which the collection probe 2 is fixed. The joint 34 is configured to move the collection probe 2 alternately at least between a position P1 in which the collection probe 2 is located in the condensation trail 5 and a position P2 in which the collection probe 2 is spaced from the condensation trail 5. The figure 3 shows the two positions P1 and P2 of the collection probe 2. The reference P1 shows the position of the collection probe 2 located in the condensation trail 5 while the reference P2 shows the position of the collection probe 2 away from the condensation trail 5. On the figure 3 , the double arrow 37 indicates the passage from position P1 to position P2 and vice versa. According to one configuration, the displacement module 32 can also bring the articulated rod 35 into another position (not shown) in which the collection probe 2 is located in a condensation trail of another reactor of the aircraft AC.

[0047] THE figures 4 et 5 represent the collection probe 2 in position P1 or position C1.

[0048] Other embodiments may be envisaged. For example, the articulated rod 35 of the second embodiment may be a retractable rod, such as the retractable rod 33 of the first embodiment.

[0049] Advantageously, the system 1 further comprises a temperature control device 10 configured to maintain the interior of the collection tube 7 at a desired operating temperature. The operating temperature may be equal to an outside temperature of the aircraft AC.

[0050] The temperature control device 10 may comprise an insulating tube 11 (shown in solid lines on the figure 1 ) at least partially enveloping the collection tube 7. The insulating tube 11 is configured to circulate between the collection tube 7 and the insulating tube 11 a refrigerant or a mixture of refrigerant and air. For example, the air with which the refrigerant is mixed may come from inside the cabin of the aircraft AC. The air inside the aircraft cabin is generally warmer than the refrigerant. The temperature control device 10 can thus regulate the temperature in the collection tube 7. The temperature control can be achieved by regulating the flow rate of the refrigerant or by regulating the flow rate of said mixture of refrigerant and air between the insulating tube 11 and the collection tube 7. Alternatively or additionally, the temperature control can be achieved by modifying the proportions of the mixture between the refrigerant and the air.

[0051] For example, the refrigerant can be liquid nitrogen.

[0052] The formation of ice crystals in the condensation trail 5 depends on the temperature of the medium in which it propagates. For example, at the outlet of the reactor 13, the medium is very hot and then cools down as one moves away from the reactor 13. The ice crystals form during cooling. The temperature control in the collection tube 7 makes it possible to simulate the temperature changes of the medium in which the condensation trail propagates. Thus, it is possible to reproduce in the collection tube 7 the evolution of the formation of ice crystals in a condensation trail 5.

[0053] Furthermore, the collection chamber 6 can be configured to be maintained at a storage temperature for the ice crystals contained in the samples 4 collected in the collection chamber 6. The temperature regulation device 10 can participate in maintaining the storage temperature for the ice crystals of the samples 4 in the collection chamber 6.

[0054] Thus, it is possible to simulate different atmospheric conditions by changing the temperature inside the collection tube 7.

[0055] The system 1 may also comprise at least one computing unit and a memory (not shown). The computing unit makes it possible to manage the system 1 by synchronizing, for example, the vacuum pump 9, the measuring devices 8 and 12 and the temperature control device 10. The memory makes it possible, for example, to store the parameters measured by the measuring devices 8 and 12 as well as the measurement conditions of the parameters. The measured parameters may be sent to a user device for processing. The computing unit may also process the measured parameters.

[0056] The invention also relates to a method of using the system 1 ( figure 6 ).

[0057] The process includes the following steps: a step E1 of collecting, by the collection probe 2, samples 4 of the condensation trail 5; a step E2 of conducting, by the collection tube 7, the samples 4 collected by the collection probe 2 to the collection chamber 6; at least one step E3 of measuring by the measuring device(s) 8 at least one characteristic parameter of the samples 4 in the collection tube 7 while they are conducted from the collection probe 2 to the collection chamber 6; a step E4 of collecting in the collection chamber 6 the samples 4 collected by the collection probe 2 and conducted by the collection tube 7.

[0058] Preferably, the collection step E1 is preceded by a preparation step. The preparation step may comprise the following sub-steps: a vacuuming sub-step, implemented by the vacuum pump 9, consisting of vacuuming the collection tube 7; a temperature regulation sub-step, implemented by the temperature regulation device 10, consisting of regulating the temperature of the collection tube 7 to a desired operating temperature; a positioning sub-step, implemented by the movement module 32, consisting of placing the collection probe 2 in the condensation trail 5; a sub-step of opening the valve of the collection probe 2.

[0059] Furthermore, the collection step E4 may be followed by a measurement step by the measuring device(s) 12 of at least one characteristic parameter of the samples 4 in the collection chamber 6.

[0060] The collection chamber 6 may contain a sampling chamber in which measurements can be made. Similarly, a sampling tube contained in the sampling chamber may allow samples to be taken from the collection chamber 6 in order to store them at a desired operating temperature for further analyses.

[0061] Thanks to system 1 and the method, it is not necessary to use a second aircraft following aircraft AC whose condensation trails 5 are to be analyzed. In addition, a probe placed far behind aircraft AC would not have allowed the nature of samples 4 to be studied. System 1 and the method also avoid the need to mount a spectrometer on the tail of aircraft AC to measure the chemical nature of condensation trails 5 behind aircraft AC. Indeed, a spectrometer placed at this location would not have allowed information to be obtained on the nature, formation and density of the ice crystals contained in samples 4.

Claims

1. A system for sampling and analyzing condensation trail generated by at least one jet engine of an aircraft in flight, wherein said system is configured to be embedded onboard the aircraft (AC) and said system comprises at least: - a collection probe (2) configured to collect samples (4) of the condensation trail (5) generated by said jet engine of said aircraft in flight; - a fixing device (3), the collection probe (2) being configured to be fixed to the aircraft (AC) by the fixing device (3), the fixing device (3) comprising: • a support (31) configured to be fixed to the fuselage of the aircraft (AC) and • a movement module (32) fixed to the support (31), wherein the movement module (32) is configured to move the collection probe (2) with respect to the aircraft (AC) to a position in which the collection probe (2) is located in the condensation trail (5); - a collection chamber (6) configured to gather the samples (4) collected by the collection probe (2); - a collection tube (7) configured to conduct the samples (4) from the collection probe (2) to the collection chamber (6); - at least one first measurement device (8) configured to measure at least one parameter characterizing the samples (4) in the collection tube (7) while said samples are conducted from the collection probe (2) to the collection chamber (6).

2. The system as claimed in claim 1, wherein said system comprises a vacuum pump (9) configured to drive the samples (4) from the collection probe (2) to the collection chamber (6).

3. The system as claimed in either one of claims 1 and 2, wherein said system comprises a temperature regulation device (10) configured to maintain the interior of the collection tube (7) at a desired operating temperature.

4. The system as claimed in claim 3, wherein the temperature regulation device (10) comprises an insulating tube (11) at least partly jacketing the collection tube (7), the insulating tube (11) being configured to circulate a refrigerant or a mix of refrigerant and air between the collection tube (7) and the insulating tube (11).

5. The system as claimed in any one of claims 1 to 4, wherein the or each of the first measurement devices (8) comprises a first measurement unit (81) configured to determine at least one parameter characteristic of a chemical composition of the samples (4).

6. The system as claimed in any one of claims 1 to 5, wherein the or each of the first measurement devices (8) comprises a second measurement unit (82) configured to determine at least one parameter characteristic of a particle size analysis of particles contained in the samples (4).

7. The system as claimed in any one of claims 1 to 6, wherein the collection chamber (6) is configured to be maintained at a temperature of conservation of the samples (4) gathered in the collection chamber (6).

8. The system as claimed in any one of claims 1 to 7, wherein said system comprises at least one second measurement device (12) configured to measure at least one parameter characteristic of the samples (4) gathered in the collection chamber (6).

9. The system as claimed in claim 8, wherein the or each of the second measurement devices (12) comprises a third measurement unit (121) configured to determine a parameter characteristic of a chemical composition of the samples (4).

10. The system as claimed in either one of claims 8 and 9, wherein the or each of the second measurement devices (12) comprises a fourth measurement unit (122) configured to determine a parameter characteristic of optical properties of the samples (4).

11. The system as claimed in claim 1, wherein the movement module (32) comprises a retractable rod (33) having a first end to which the collection probe (2) is fixed, the retractable rod (33) being configured to alternately assume at least a first configuration in which the retractable rod (33) is extended to bring the collection probe (2) into a first position (C1) in which the collection probe (2) is located in the condensation trail (5) and a second configuration in which the retractable rod (33) is retracted to distance the collection probe (2) from the condensation trail (5) in a second position (C2).

12. The system as claimed in either one of claims 1 and 12, wherein the movement module (32) comprises an articulated rod (35), the articulated rod (35) having a first end comprising an articulation (34) fixed to the support (31) and a second end to which the collection probe (2) is fixed, the articulation (34) being configured to move the collection probe (2) alternately at least between a third position (P1) in which the collection probe (2) is located in the condensation trail (5) and a fourth position (P2) in which the collection probe (2) is separated from the condensation trail (5).

13. A method for using a system for sampling and analyzing condensation trail generated by at least one jet engine of an aircraft in flight as claimed in any one of claims 1 to 12, wherein said method comprises the following steps: - a step (E1) of collection, by the collection probe (2), of samples (4) of the condensation trail (5) generated by said jet engine of said aircraft in flight; - a step (E2) of conducting, by the collection tube (7), of the samples (4) collected by the collection probe (2) to the collection chamber (6); - at least one step (E3) of measurement, by the first measurement device or devices (8), of at least one parameter characteristic of the samples (4) in the collection tube (7) while said samples are conducted from the collection probe (2) to the collection chamber (6); - a step (E4) of collection, in the collection chamber (6), of the samples (4) collected by the collection probe (2) and conducted by the collection tube (7).

14. An aircraft, wherein said aircraft comprises a sampling and analysis system (1) as claimed in any one of claims 1 to 12.