Absorbent cartridge for collecting liquid dripping from the end of a tube

Abstract

Absorbent Cartridge for Recovering Liquid Drips from the End of a Tube. The invention relates to an assembly (2) for a turbomachine (1) comprising: a tube portion (10) with axis X terminating in an outlet end (11) for an oiled fluid (12); a cartridge (14) for recovering said fluid, a storage portion (19) of which is disposed under the tube portion and a collection portion (20) of which extends along X beyond said end; and removable means (15) for attaching the cartridge to the tube portion. Furthermore, this cartridge comprises: a housing (21), having a bottom wall (22), at least one side wall (23), and an upper face (24) directed towards the tube portion and open at least in the collection portion; and a spongy element (27) housed in the housing and extending into the collection portion and the storage portion. Figure to be published with the abbreviation: Figure 2

Description

Title of the invention: Absorbent cartridge for recovering liquid dripping from the end of a tube. TECHNICAL FIELD OF THE INVENTION

[0001] The present invention relates to a device for recovering a liquid that may drip from the end of a tube. Advantageously, it may be a device for recovering dripping oil, placed under the end of a tube through which oily air escapes.

[0002] More specifically, the invention may relate to an absorbent cartridge for recovering dripping oil, fixed under the end of an oiled air ejection tube opening into the secondary flow of a turbomachine, and intended to collect and store the dripping oil flowing from this tube when the turbomachine is stopped.

[0003] The invention finds applications in the field of aircraft turbomachinery and their maintenance. TECHNOLOGICAL BACKGROUND OF THE INVENTION

[0004] In aircraft turbomachinery, it is common practice to depressurize the housings containing the bearings and other lubricated components to prevent oil from escaping. This is done by drawing some of the air from these housings and sending it to an oil separator, which separates the air from the oil it contains, in order to recover the oil and return it to the lubrication system. The air exiting the oil separator is typically discharged into the downstream section of the turbomachine's secondary flow, via an ejection tube opening upstream of the nozzle. This air then mixes with the airflow circulating in the secondary flow.

[0005] Since the oil separator's efficiency is not perfect, the air exiting the oil separator still contains a small amount of oil, which is sent via the ejection tube into the secondary flow of the turbomachine. This poses no problem as long as the turbomachine is running. Indeed, this oil is then carried away as suspended droplets by the high-speed airflow circulating in the secondary flow and conducted to the exhaust.

[0006] However, when the turbomachine stops, the oil contained in the air exiting the ejection tube is no longer carried away by the gas flow, because there is no longer any air circulation in the secondary flow. It then trickles from the tube in the form of liquid droplets falling by gravity below the end of the ejection tube.

[0007] If a hot part of the turbomachine, such as the mixer or the exhaust cone, is located under the end of the ejection tube, significant fumes are generated when these oil droplets drip These fumes come into contact with this component, which remains hot long after the turbomachine has shut down. Although they do not pose any safety risk, these fumes are unacceptable because they are viewed very negatively by aircraft manufacturers, crew members, and passengers. They must therefore be avoided at all costs. Summary of the invention

[0008] The invention aims to solve this problem by proposing a device that can be used to store the dripping oil flowing from the ejection tube, thus preventing the formation of fumes when the turbomachine is stopped.

[0009] To this end, a first aspect of the invention teaches an assembly for a turbomachine comprising: • a portion of an oiled fluid ejection tube, said portion of the tube having axis X and ending with an oiled fluid outlet end; • a cartridge for recovering said oiled fluid, a first part of which, called the storage part, is disposed under the portion of tube and a second part, called the collection part, extends along the X axis beyond said end; and • removable means for attaching the cartridge to said portion of tube.

[0010] In addition, this cartridge comprises: • a casing, comprising a bottom wall, at least one side wall, and a top face which is directed towards the portion of the tube and open at least in the collection section; and • a spongy material element, housed in the casing and extending into the collection part and into at least part of the storage part.

[0011] The X-axis corresponds to the axis of the tube portion and not of the complete tube (which may be curved), that is to say, to the axis of the substantially straight portion of the tube that terminates at the end. It corresponds to the longitudinal direction of this tube portion, which is parallel to the tangential direction in the case of a tube curved at its end.

[0012] A spongy material element is understood to mean an assembly of one or more juxtaposed pieces of a porous and alveolar absorbent material, capable of absorbing a liquid and retaining it in its alveoli.

[0013] Advantageously, the cartridge allows the liquid dripping from the end of the tube portion to be collected and stored. The formation of fumes is thus avoided.

[0014] As the recovery cartridge is located under the portion of tube with its collection part extending beyond the end of the portion of tube, the drops of liquid that trickle from the end of the portion of tube fall by gravity into the collection part of the cartridge.

[0015] The upper face of the casing being open at the collection area, these droplets enter the casing and fall on the spongy material element contained therein and present in the collection area.

[0016] The porous nature of the spongy material advantageously allows it to absorb the liquid and retain it within its cavities. Furthermore, the liquid diffuses by capillary action throughout the spongy material element and is thus advantageously conducted and retained in the storage portion of the cartridge, even if the cartridge is not horizontal or inclined with its storage portion lower than the collection portion.

[0017] According to the embodiment, the cartridge can instead be inclined with its storage section higher than the collection section. Thanks to the spongy material element, the liquid does not overflow and can still be conveyed and retained in the storage section. The quantity of liquid that can be stored in the cartridge is thus much greater than with a simple reservoir.

[0018] The housing protects the spongy material element, particularly from crushing and abrasion. Furthermore, it provides the cartridge with a certain degree of sealing and satisfactory mechanical strength, which facilitates its attachment to the tube section.

[0019] The fastening means ensure suitable relative positioning between the tube portion and the cartridge. Being removable, they can be taken off to change the cartridge in its entirety, empty it, or replace only the spongy material element when the cartridge is filled with liquid.

[0020] Advantageously, the recovery cartridge can extend substantially parallel to the portion of tube, which limits the impact of its presence on the air flow in the secondary vein.

[0021] Thanks to the original design of the cartridge with its spongy material element, such an arrangement is possible regardless of the orientation of the portion of the tube and even if the X axis is inclined with respect to the horizontal downwards on the end side of the portion of the tube.

[0022] Advantageously, the housing is preferably fixed to the tube section with a gap between zero and two millimeters. The cartridge is thus pressed against the tube section or fixed to it with a small gap corresponding to a slight mounting clearance. The impact of the cartridge's presence on the airflow in the secondary channel thus remains very low.

[0023] The cartridge is largely disposed under the tube portion and protrudes from the tube portion only by its limited collection section. Advantageously, the length of the collection section along the X-axis preferably represents less than half, preferably less than a quarter, and even more preferably less than ten percent of the overall length of the cartridge along the X-axis.

[0024] This short overhang allows only the liquid that flows over the end of the tube portion to be collected, and not the suspended liquid droplets that are carried further by the gas flow. Only the targeted portion of the oiled fluid that flows over is thus collected and stored in the cartridge, which fills slowly. This reduces the frequency of cartridge replacement or emptying.

[0025] Advantageously, the collection part can protrude along the X axis by a length of between five and ten millimeters beyond the end of the portion of the tube.

[0026] Such an overhang is perfectly suited to the intended application example. It is long enough to allow satisfactory collection of the oil dripping from the oiled air ejection tube when the turbomachine is stopped, but short enough not to capture the suspended oil droplets that are carried further downstream in the nozzle by the airflow of the secondary duct when the turbomachine is running.

[0027] Advantageously, the spongy material element can extend throughout the entire casing, that is, along the entire length (along the X-axis) of the hollow internal volume of the casing. It thus extends both into the collection area and into the entire storage area of ​​the casing.

[0028] A larger storage volume is thus provided. The liquid can pass by capillary action throughout the entire sponge element, from the collection area where it flows to the entire storage area occupied by the sponge element. The storage capacity is thus maximized.

[0029] Advantageously, the top face of the housing and / or one of its side faces can be fully opened. This reduces the weight of the cartridge.

[0030] Furthermore, it is easier to remove the spongy element from the housing for replacement when it is saturated with liquid. It can thus be replaced with a new spongy element while retaining the housing.

[0031] If the fastening means used allow it, this change can even be carried out without having to disassemble the housing.

[0032] Alternatively, one or more side faces of the housing can be closed by a removable, sliding or pivoting wall.

[0033] Furthermore, when the open lateral face is the downstream lateral face, a larger contact area with the spongy material element is offered to the droplets, which improves the collection and absorption of the dripping liquid.

[0034] Advantageously, the housing can be made of metal or plastic. These materials offer suitable mechanical protection for the spongy element and good sealing to contain the liquid.

[0035] Furthermore, the spongy material element can be made of synthetic sponge or metallic foam. Such materials are lightweight and have properties absorbents adapted to the intended applications. As an example, one can cite the nickel and chromium based metallic foam marketed under the name Retimet® by the company Dunlop-equipement.

[0036] Advantageously, the casing and the spongy material element can be parallelepiped-shaped. Such a shape is simple to produce while also being suitable for the shape of a section of tube.

[0037] Advantageously, the removable fastening means comprise at least one screw that passes through the cartridge and a wall of the tube portion. Such fastening means are strong, reliable, economical, and easy to implement. Moreover, they can be very easily removed and replaced to replace the cartridge.

[0038] Advantageously, the assembly according to the invention may further include a device for detecting the filling of the cartridge.

[0039] This device advantageously detects whether the cartridge is full. This device can be checked during routine maintenance to determine whether the cartridge needs to be changed or emptied. It can also send a signal to the crew or maintenance operators when the cartridge is full, so that a replacement / emptying operation can be scheduled.

[0040] In the event that the assembly does not include a detection device, the filling speed of the cartridge can be estimated based on the flow rate of liquid flowing in the portion of the tube and a replacement / emptying frequency of the cartridge can be recommended.

[0041] A second aspect of the invention relates to an aircraft turbomachine comprising an assembly as described above.

[0042] More specifically, this aircraft turbomachine may advantageously be a turbofan engine comprising: • a secondary stream, delimited by an outer wall and an inner wall that are substantially cylindrical and concentric, extending from a blower to an exhaust nozzle and through which a portion of the air drawn in by the blower circulates; and • an air ejection tube exiting an oil separator and ending in the downstream part of the secondary vein by said portion of tube which opens at its end upstream of the nozzle.

[0043] 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

[0044] The figures are presented for illustrative purposes only and are in no way limiting of the invention.

[0045] [Fig-1] is a schematic cross-sectional view of an example of an oiled air ejection tube of a turbomachine illustrating the technical problem to be solved.

[0046] [Fig.2], [Fig.3] and [Fig.4] are schematic cross-sectional views respectively of a first example, a second example and a third example of the assembly according to the invention.

[0047] [Fig. 5], [Fig. 6] and [Fig. 7] are perspective top views of the cartouche of the assembly examples of [Fig. 2], [Fig. 3] and [Fig. 4] respectively, shown alone. DETAILED DESCRIPTION

[0048] Unless otherwise specified, the same element appearing on different figures has a unique reference.

[0049] In the present application, the terms "upstream" and "downstream" are defined with respect to the normal direction of gas flow (upstream to downstream) through a turbomachine.

[0050] The "turbomachine axis" is the longitudinal axis of the turbomachine corresponding to the axis of rotation of the turbomachine's rotor. A radial direction is a direction perpendicular to the turbomachine axis and intersecting this axis.

[0051] Unless otherwise specified, the adjectives "internal" and "external" are used in this application with reference to a radial direction such that the internal part of an element is, along a radial direction, closer to the axis of the turbomachine than the external part of the same element.

[0052] The terms "up", "down", "lower" and "upper" are defined in terms of the normal orientation of the turbomachine when installed in an aircraft flying horizontally and upright. This orientation corresponds to that shown in the figures.

[0053] Figure 1 schematically represents a portion of a turbomachine 1 in which an assembly 2 according to the invention could advantageously be installed. This is, for example, a turbofan engine.

[0054] The turbomachine portion 1 shown comprises an outer wall 3 ('outer fan duct' or OFD) and an inner wall 4 ('inner fan duct' or IFD) substantially cylindrical which extend inside each other.

[0055] They delimit between themselves an annular space of air flow constituting the secondary vein 5 (also called blower duct or "fan duct" in English), which extends from the blower to the exhaust nozzle 6 and in which part of the air drawn in by the blower circulates.

[0056] The other part of the air drawn in by the blower circulates in the primary vein (not shown) before also being sent into the exhaust nozzle 6.

[0057] A mixer 8, disposed at the inlet of the exhaust nozzle 6, is shaped to ensure the mixing around an exhaust cone of the gases exiting the primary vein with the airflow exiting the secondary vein 5.

[0058] As the gases exiting the primary stream are very hot after passing through the combustion chamber, their contact gives the mixer and the exhaust cone a temperature above 250°C, which remains high long after the turbomachine 1 has stopped.

[0059] Conventionally, an air ejection tube 9 exiting the oil separator terminates in the downstream part of the secondary vein 5 by a portion of tube 10 with axis X which opens at its end 11 upstream of the nozzle 6. As it still contains a small proportion of oil, the air exiting this tube 9 is called oiled air or oiled fluid.

[0060] When the turbomachine is in operation, the oiled air exiting the tube 9 is rapidly carried downstream of the nozzle 6 by the large airflow from the secondary vein 5. The oil droplets it contains then remain suspended in this flow and are carried downstream without running off the end 11 of the portion of tube 10.

[0061] When the turbomachine 1 stops, the airflow from the secondary duct 5 stops and an oily fluid 12, composed of oil droplets 13, begins to trickle down the end 11 of the tube portion 10 and falls by gravity onto the parts below, namely, in the example shown, the mixer 8, which is still very hot. Fumaroles are then generated.

[0062] Several examples of assembly 2 according to the invention, allowing this situation to be avoided, have been shown in figures 2 to 4.

[0063] In addition to the tube portion 10, these assemblies 2 include a cartridge 14 for recovering the oiled fluid 12 which is placed under the tube portion 10 and preferably extends parallel or substantially parallel to the tube portion 10 and its axis X. It is attached to it in a removable manner by fastening means 15.

[0064] These removable fixing means 15 are, for example, as shown, screws 16 which pass through the cartridge 14 and the wall 17 of the portion of tube 10 and cooperate with nuts 18, preferably self-locking to simplify screwing / unscrewing and flush with the wall 17 so as not to disturb the flow of air inside the portion of tube 10.

[0065] Other removable fastening means 15 can be used alternatively, for example fastening clips, one or more clamps surrounding the cartridge 14 and the tube portion 10, or additional attachment means carried by the cartridge 14 on the one hand and the tube portion 10 on the other hand, in particular an additional rail / slide or rib / groove assembly.

[0066] The cartridge 14 is placed under the portion of tube 10, so as to protrude slightly beyond the end 11 in the direction of the X axis. It thus comprises a first part, called the storage part 19, which is located under the portion of tube 10 and a second part, called the collection part 20, which protrudes beyond the portion of tube 10.

[0067] The cartridge 14, which is illustrated alone in figures 5 to 7, comprises a case 21, for example of parallelepiped shape, which has a bottom wall 22 and one or more side walls 23 depending on its shape.

[0068] The upper face 24 of the housing 21, which is oriented towards the portion of the tube 10, can be completely open or partially closed by an upper wall 25. In all cases, it has an opening 26 at the level of the collection part 20 through which the drops 13 of oiled fluid 12 can pass.

[0069] Thus for example, in figures 2 and 5, the housing 21 has a bottom wall 22, four side walls 23 and a top wall 25 with an opening 26 at the level of the collection part 20.

[0070] In figures 3 and 6, the housing 21 has a bottom wall 22, three side walls 23 and a top wall 25 with an opening 26 at the collection part 20. It does not have a side wall at its downstream side face 28 which is completely open.

[0071] In figures 4 and 7, the housing 21 has a bottom wall 22 and four side walls 23. It does not have a top wall, its upper face 24 being completely open.

[0072] The set of these walls 22, 23, 25 define a hollow interior volume in which is housed an element made of spongy material 27.

[0073] This element 27 extends preferentially throughout the entire housing 21 as illustrated in [Fig.7].

[0074] Alternatively, it may occupy only part of the internal volume of the housing 21. In this case, it occupies at least the collection part 20 and thus extends under the opening 26. The drops 13 of oiled fluid 12 which pass through the opening 26 are thus absorbed and retained by the spongy material element 27.

[0075] The housing 21 may also include one or more openings in its side walls 23, or even have one or more fully open side faces as illustrated for example in [Fig.6].

[0076] In addition to a weight saving, such an open face can allow the sponge material element 27 to be changed when it is completely saturated with oil, without having to replace the housing 21. Depending on the fastening means 15 used, this change can even be carried out without dismantling the housing 21.

[0077] When the open lateral face is the downstream lateral face 28 as in [Fig.6], a larger contact area with the spongy material element 27 is offered to the drops 13, which improves the collection and absorption of the oiled fluid 12.

[0078] As can be seen in figures 5 to 7, through passages 29 can also be provided through the housing 21 and possibly the spongy material element 27 to allow the passage of the fastening means 15 if necessary.

[0079] Assembly 2 can also be equipped with a detection device 30, an example of which has been schematically represented in [Fig. 7]. This device advantageously makes it possible to monitor the filling of the cartridge 14 and to indicate when it is full, so that a maintenance operation to replace it can then be planned.

[0080] Such a detection device 30 may include, in particular, a presence or liquid level sensor, a cartridge weight sensor 14, or any other suitable device readily conceivable by a person skilled in the art.

Claims

Demands

1. Assembly (2) for a turbomachine (1) comprising a portion of a tube (10) for ejecting oiled fluid, said portion of the tube (10) having axis X and terminating in an end (11) for the outlet of the oiled fluid (12), assembly (2) characterized in that it further comprises: - a cartridge (14) for recovering said oiled fluid, a first part of which, called the storage part (19), is disposed under the portion of the tube (10) and a second part of which, called the collection part (20), extends along axis X beyond said end (11); and - removable means (15) for attaching the cartridge (14) to said portion of the tube (10); and in that the cartridge (14) comprises: - a casing (21), having a bottom wall (22), at least one side wall (23), and a top face (24) which is directed towards the portion of tube (10) and open at least in the collection part (20);and - a spongy material element (27), housed in the casing (21) and extending into the collection part (20) and into at least a part of the storage part (19).;

2. Assembly (2) according to claim 1 characterized in that the housing (21) is fixed to the portion of tube (10) with a gap between zero and two millimeters.

3. Assembly (2) according to any one of the preceding claims characterized in that the length of the collection portion (20) along the X axis represents less than ten percent of the overall length of the cartridge (14) along the X axis.

4. Assembly (2) according to any one of the preceding claims characterized in that the collection part (20) extends along the X axis by a length of between five and ten millimeters beyond the end (11).

5. Assembly (2) according to any one of the preceding claims characterized in that the upper face (24) of the housing (21) and / or one of its side faces (28) is fully open.

6. Assembly (2) according to any one of the preceding claims characterized in that the housing (21) is made of metal or plastic.

7. Assembly (2) according to any one of the preceding claims characterized in that the spongy material element (27) is made of synthetic sponge or metallic foam.

8. Assembly (2) according to any one of the preceding claims characterized in that it further comprises a device for detecting the filling of the cartridge (14).

9. Aircraft turbomachine (1) comprising an assembly (2) according to any one of the preceding claims.

10. Aircraft turbomachine (1) according to claim 9 characterized in that it is a turbofan engine comprising: - a secondary duct (5), delimited by an outer wall (3) and an inner wall (4) substantially cylindrical and concentric, which extends from a fan to an exhaust nozzle (6) and in which a portion of the air drawn in by the fan flows; and - an air ejection tube (9) exiting an oil separator and terminating in the downstream part of the secondary duct (5) by said portion of tube (10) which opens at its end (11) upstream of the nozzle (6).

Images