Fluid machine with side channel

Abstract

The invention relates to a fluid machine (1) comprising a stator (2) and a rotor (4) rotatably mounted inside the stator (4), the stator (2) comprising a central zone (25) around which extends a side channel (22) through which the fluid is intended to flow as a result of a rotation of the rotor (4) or with a view to rotating the rotor (4), the side channel (22) being formed by an inner wall (27) of the stator (2) and having a first rim (22a) and a second rim (22b) between which a sealing barrier (28) extends, characterised in that the stator (2) comprises an insert (8) which is arranged in the side channel (22) so as to form, in the stator (2), an additional inner wall (81) intended to be swept by the flowing fluid and to guide the fluid in the side channel (22).

Description

Side channel fluid machine

[0001] The invention relates to a side channel fluid machine, also called a regenerative machine. It can be a side channel pump, fan or compressor.

[0002] As a pump, the fluid machine according to the invention can be used, for example, in the dilution of Helium 3 in Helium 4. This is called a cryo-pump. As a ventilator, the fluid machine according to the invention can be used, for example, as a respirator for medical use.

[0003] The term "fluid machine" or "fluid processing" machine means a machine configured to convert energy stored by a fluid into mechanical energy or vice versa. The term "side channel" means a peripheral channel around a central area of ​​the machine and which has a mean plane parallel to two opposite flat faces of the machine.

[0004] A side channel fluid machine comprises, in known manner, a stator and a rotor rotatably mounted inside the stator. The stator comprises a central zone around which extends a side channel intended for a flow of the fluid under the effect of a rotation of the rotor or for the purpose of a rotation of the rotor. In particular, the side channel is formed by an internal wall of the stator and has a first rim and a second rim between which extends a sealing dam.

[0005] Such a machine, particularly in its compressor or fan configuration, is increasingly used for industrial applications where medium flow rates are required with low or medium compression ratios. Furthermore, when well insulated acoustically, such a machine can be very quiet, which is a major selection criterion in certain cases. Finally, unlike other volumetric machines, such a machine allows control and operability over a wide operating range with a minimum of moving mechanical parts.

[0006] Compared with a centrifugal impeller, the side channel fluid machine has the advantage of being easily manufactured with relatively simple geometric shapes (mainly consisting of 2D sketch extrusion). In addition, it is also very simple to design the machine designs to achieve different objectives meeting various specifications.

[0007] It should be noted that a side channel fluid machine can very easily be placed in multi-stage without much concern about pumping phenomena. The stages can be arranged in parallel to increase the flow rate, or in series to increase the pressure. Adaptability between the stages is very easy in both aeraulics and architecture and mechanics (very simple piping between the stages).

[0008] Despite the advantages listed above, manufacturers of side channel fluid machines are constantly looking for technical solutions capable of improving the performance of these machines, particularly with regard to flow rate and compression ratio.

[0009] One aim of the invention is to propose such a solution.

[0010] To this end, the machine according to the invention, moreover in accordance with the generic definition given in the preamble above, is essentially characterized in that the stator comprises an insert which is arranged in the lateral channel so as to form or introduce into the stator an additional internal deflecting wall intended to be swept by the flowing fluid and to guide the fluid into the lateral channel.

[0011] By providing an insert in the lateral channel, the invention makes it possible to improve the flow rate and compression rate of fluid delivered at the outlet of the machine.

[0012] Furthermore, embodiments of the invention may comprise one or more of the following features: - the stator comprises a suction duct and a fluid discharge duct; - the suction and discharge ducts each have one end in fluid communication with the lateral channel and one end intended to be in communication with an external environment; - the suction duct opens into the lateral channel at or near the first rim; - the discharge duct opens into the lateral channel at or near the second rim; - the insert is formed around the central area of ​​the stator; - the insert is held in suspension in the lateral channel by means of a stator support; - the support is formed by the sealing dam; - the insert has a first end and a second end arranged on either side of the sealing dam;- the support comprises at least one tab which extends from the inner wall forming the lateral channel;- the insert bears on the at least one tab;- the at least one tab has an aerodynamic profile configured to facilitate the flow of fluid in the lateral channel;- the support comprises two tabs positioned on either side of the sealing dam;- the lateral channel extends over an arc-shaped sector around the central part of the stator;- the insert extends over an arc-shaped sector around the central part of the stator;- the lateral channel has an arc length preferably between 290° and 350°;- the insert has an arc length preferably between 290° and 350°;- the lateral channel has in a vertical transverse plane a section in the form of a portion of a disc;- the insert has in a vertical transverse plane a section in the form of a portion of a disc;- the stator comprises a lower part and an upper part assembled against each other;- the lower part of the stator comprises the suction duct, the discharge duct and the insert;- the upper part of the stator comprises a housing configured to receive the rotor;- the rotor comprises a wheel provided with a plurality of peripheral fins;- the wheel rests on the central part of the stator;- the fins are arranged projecting towards the lateral channel and opposite the insert;- the machine is a fan, a compressor or a pump.;

[0013] The invention may also relate to any side channel fluid machine comprising any combination of the above or below features within the scope of the claims.

[0014]

[0015] Other features and advantages will appear on reading the description below, made with reference to the following figures in which:

[0016] is an exploded isometric view partially illustrating a side channel machine according to the invention; the machine comprising a stator and a rotor;

[0017] is an isometric view illustrating the machine in its assembled configuration;

[0018] is an isometric sectional view partially illustrating the machine without the rotor, with a side channel and an insert at the stator;

[0019] is an isometric top view illustrating a first portion of the stator including the insert;

[0020] is an isometric view partially illustrating the machine with fluid flow around the insert and between rotor blades.

[0021] The invention relates to a side channel fluid machine 1, also referred to in the following description as a "regenerative machine" or "machine".

[0022] As illustrated in , the machine 1 comprises a stator 2 and a rotor 4 which is rotatably mounted inside the stator 2.

[0023] In particular, the stator 2 comprises two opposite main faces F1, F2 which extend in a plane parallel to a plane H, called the horizontal plane. The direction Z perpendicular to the horizontal plane H is called the main or vertical direction of the machine 1. Between the main faces F1, F2 of the stator 2 extends a lateral or peripheral face F3.

[0024] With reference to the, the stator 2 comprises a main housing 21 intended to receive the rotor 4, as well as a lateral channel 22 intended for a flow of a fluid under the effect of a rotation of the rotor 4 or with a view to a rotation of the rotor 4. In addition, the stator 2 comprises a conduit 23 for suction of the fluid to bring it into the lateral channel 22, and a conduit 24 for delivery of the fluid to discharge it out of the lateral channel 22. The suction conduit 23 is visible at the.

[0025] In particular, the main housing 21 and the lateral channel 22 extend between the main faces F1, F2 of the stator 2, each along a mean plane substantially parallel to the main faces F1, F2. In other words, the main housing 21 and the lateral channel 22 each extend along a horizontal mean plane. The lateral channel 22 surrounds the main housing 21 so that together they form a single cavity. In a horizontal plane, the lateral channel 22 has, for example, the shape of an arc of a circle.

[0026] With reference to the, the lateral channel 22 is formed between a central zone 25 and a peripheral zone 26 of the stator 2. In particular, the central zone 25 of the stator 2 can form a central core of material of cylindrical shape around which the lateral channel 22 extends. The central zone 25 and the peripheral zone 26 define an internal wall 27 which delimits the lateral channel 22. In addition, the central zone 25 is connected to the peripheral zone 26 by a radial strip, called a sealing dam 28.

[0027] The sealing dam 28 forms a shoulder in the lateral channel 22. In addition, the sealing dam 28 defines two opposite edges 22a, 22b of the lateral channel 22. Finally, the sealing dam 28 forms with the central zone 25 a sealing system whose function will be detailed later. In the example illustrated, the sealing dam 28 is made in one piece with the rest of the stator 2.

[0028] Still with reference to the, the suction duct 23 opens into the lateral channel 22 at a first region 22c located near the first rim 22a of the lateral channel 22. The discharge duct 24 communicates with the lateral channel 22 at a second region 22d located near the second rim 22b of the lateral channel 22. In the example illustrated, the suction duct 23 and the discharge duct 24 each extend in a vertical direction (or transverse to the horizontal plane). Alternatively, these ducts 23, 24 may extend in a radial direction, i.e. perpendicularly or at an angle relative to the main direction of the machine 1.

[0029] The fluid expelled through the discharge conduit 24 has a pressure higher than that of the fluid admitted at the suction conduit 23. In other words, between the suction conduit 23 and the discharge conduit 24, the fluid is compressed by the action of the rotor 4 during the flow in the lateral channel 22. The first region 22c into which the suction conduit 23 opens is thus called the “low pressure region”. The second region 22d into which the discharge conduit 24 opens is thus called the “high pressure region”.

[0030] Thus, the sealing dam 28, which separates the edges 22a, 22b of the lateral channel 22 also forms a separating member between the high pressure region 22c and the low pressure region 22d of the lateral channel 22. In other words, the sealing dam 28 makes it possible to prevent the fluid that has been compressed during the flow through the lateral channel 22 from returning to the suction duct 23. Conversely, the sealing dam 28 makes it possible to prevent the fluid admitted at the suction duct 23 from passing directly to the discharge duct 24 without passing through a compression step through the lateral channel 22.

[0031] The central zone 25 of the stator 2, which is formed in the continuity of the sealing dam 28, also ensures the functions described above.

[0032] Referring again to the, the rotor 4 is rotatably mounted on itself around an axis perpendicular to the horizontal plane H, thanks to a motor 6 (visible in the). In addition, the rotor 4 comprises a wheel 41 equipped with peripheral vanes 42. In particular, the wheel 41 is housed in the main housing 21 and rests on the central zone 25 of the stator 2. The vanes 42 project towards the lateral channel 22.

[0033] In order to ensure a coupling between the rotor 4 and the motor 6, the stator 2 comprises, with reference again to the, two secondary passages or housings 29a, 29b intended to receive an axis (not illustrated) for driving the rotor 4 in rotation. The secondary housings 29a, 29b are arranged for example along the main direction Z of the machine 1 (i.e. perpendicular to the horizontal plane H), on either side of the main housing 21.

[0034] According to the invention, the stator 2 comprises an insert 8 which is arranged in the lateral channel 22 so as to form in the stator 2 an additional deflecting internal wall 81 intended to be swept by the flowing fluid and to guide this fluid into the lateral channel 22. This insert 8 preferably extends in an arc of a circle over the entire length of the lateral channel 22 (in a horizontal plane). The term “additional” is defined in relation to the internal wall 27 which forms or delimits the lateral channel 22.

[0035] Thus, thanks to this double internal wall 27, 81 swept by the flowing fluid, the invention makes it possible to increase the flow rate and the compression rate of the fluid delivered at the outlet of the machine 1.

[0036] Advantageously, as illustrated in Figures 3 and 4, the insert 8 is mounted in suspension in the lateral channel 22. Thus, the fluid flowing in the lateral channel 22 circulates around the insert 8. The flow of the fluid in the lateral channel 22 is thus better guided thanks to the presence of the insert 8.

[0037] The term “suspension” means that the insert 8 has a side wall 81 which is not in contact with the internal wall 27 which delimits the lateral channel 22, except by means of a support 9 separate from the internal wall 27. In other words, the insert 8 is not in direct contact with the internal wall 27 which delimits the lateral channel 22.

[0038] Advantageously, the support 9 of the insert 6 can be formed by the sealing dam 28. The insert 8 then has ends 82, 83 which are fixed on either side of the sealing dam 28. In the example illustrated, the ends 82, 83 of the insert 6 are carried by the edges 22a, 22b of the lateral channel 22.

[0039] The support 9 may also be formed by at least one tab 91, 92 which extends into the lateral channel 22 from the internal wall 27 delimiting the lateral channel 22. The lateral face 81 of the insert 8 bears on the at least one tab 91, 92.

[0040] It should be noted that the at least one leg 91, 92 advantageously has an aerodynamic profile configured to promote the flow of fluid in the lateral channel 22 (for example an aerodynamic profile to cope with the flow of fluid). Furthermore, the at least one leg 91, 92 may be in addition to the sealing dam 28. Such a combination provides better stability to the insert 8 in the lateral channel 22.

[0041] In the example illustrated, the insert 8 is held in suspension in the lateral channel 22 by means of a support comprising the sealing dam 28 and two legs 91, 92. The legs 91, 92 are arranged equidistant from the sealing dam 28. Here, the legs 91, 92 are spaced from each other by 120° measured around a central vertical axis of the machine 1.

[0042] Advantageously, as illustrated in the, the stator 2 may comprise two distinct parts 2A, 2B. These parts 2A, 2B may be manufactured separately (for example by additive manufacturing) then assembled along a horizontal plane H to form a single block illustrated in the. In addition, these parts 2A, 2B each carry a main face F1, F2 of the stator 2 and a secondary housing 29a, 29b intended for the passage of the rotational drive shaft of the rotor 4. After assembly, the parts 2A, 2B of the stator 2 form the lateral face F3 of the stator 2.

[0043] One of the parts 2A, 2B of the stator 2, here the part 2A, comprises the central zone 25, the suction duct 23, the discharge duct 24, the insert 8, and a portion 27a of the wall 27 which delimits the lateral channel 22. The other of the parts 2A, 2B of the stator 2, here the part 2B, comprises the main housing 21 intended to receive the rotor 4 as well as a portion 27b of the wall 27 which delimits the lateral channel 22.

[0044] It should be noted that, in the example illustrated, the secondary housing 29b provided at the level of the part 2B of the stator 2 opens onto the external face F2 associated with this part 2B. This makes it possible to connect the rotational drive axis of the rotor 4 to the motor 6 positioned outside the stator 2. On the other hand, the secondary housing 29a provided at the level of the part 2A of the stator 2 is blind, that is to say does not open onto the main face F1 associated with this part 2A. The housing 29a is formed in the central zone 25 of the stator 2.

[0045] Advantageously, as illustrated in particular in the, the internal wall 27 delimiting the lateral channel 22, as well as the lateral wall 81 delimiting the insert 8, can have a quasi-toroidal shape around the central zone 25 of the stator 2. In other words, according to a top view of the part 2A of the stator 2 (see), the lateral channel 22 (respectively the insert 8) can extend over a sector in the form of an arc of a circle defined between the first rim 22a and the second rim 22b. This sector has an arc length advantageously between 290 and 350°

[0046] The quasi-toroidal shape here means a surface or a solid generated by an incomplete revolution of a closed plane curve (generating curve) around an axis located in the plane of this closed plane curve. The axis of revolution does not pass through the center of the generating curve. The closed plane curve can for example be a circle, a square, a rhombus, etc.

[0047] In the illustrated example, the internal wall 27 delimiting the lateral channel 22 is generated by a generating curve in the shape of a circle. In other words, the lateral channel 22 has a circular-shaped section in a vertical transverse plane. The lateral wall 81 delimiting the insert 8 is generated by a generating curve in the shape of a portion of a disc. In other words, the insert 8 has a half-disc-shaped section in a vertical transverse plane.

[0048] In the illustrated example, the respective sections of the lateral channel 22 and the insert 8 are constant. Alternatively, these sections may be variable around the main direction of the machine 1. In particular, the section of the lateral channel 22 may decrease from the low pressure region 22d to the high pressure region 22c. Such a configuration promotes an increase or a decrease in the pressure of the fluid flowing in the lateral channel between the suction duct 23 and the discharge duct 24.

[0049] Referring again to the, it should be noted that the sealing dam 28 also extends over a sector in the shape of an arc of a circle. This sector has an arc length advantageously between 10 and 70°. Furthermore, this sector is complementary to that associated with the lateral channel 22, so that the sealing dam 28 and the lateral channel 22 make a complete turn around the central zone 25 of the stator 2.

[0050] Advantageously, as illustrated in , the peripheral wall 81 of the insert 8 may comprise a first curved portion 81a of convex shape and a second curved portion 81b of planar shape. The two portions 81a and 81b are for example oriented in opposite directions in a direction perpendicular to the horizontal plane H. The first convex portion 81a is arranged for example opposite the part 2A of the stator 2, and in particular opposite the portion 27a of the internal wall 27. The second planar portion 81b is turned for example towards the rotor 4 (not illustrated) in the direction of the part 2B of the stator 2.

[0051] Advantageously, with reference again to the, the rotor 4 may have a general dome shape. In particular, the wheel 41 of the rotor 4 may have a flat horizontal face and a concave lateral face. The fins 42 of the rotor 4 may each be formed by a portion of disk, for example a half-disk, which extends radially from the concave lateral face of the wheel 41. In other words, the fins 42 may each have a convex face which at least partly matches the concave shape of the lateral face of the wheel 41, and a flat face 42a in a horizontal plane. The respective flat faces 42a of the fins 42 are arranged opposite the flat portion 81b of the insert 8.

[0052] In the example illustrated, the fins 42 are flat and arranged radially relative to the wheel 41, that is to say perpendicular to the main direction of the machine 1. Alternatively, the fins 42 may be left-handed and arranged at an angle relative to the main direction of the machine 1.

[0053] Advantageously, the suction duct 23 has a diameter greater than that of the discharge duct 24. Furthermore, the suction duct 23 and the discharge duct 24 open into the lateral channel 22 from one of the main faces F1, F2 of the stator, here the face F1. In a variant not illustrated, the ducts 23, 24 can open into the lateral channel 22 from the peripheral face F3 of the stator 2.

[0054] In another embodiment not illustrated, the insert 8 is formed by vanes formed on the internal wall 27 forming the lateral channel 22. These vanes also introduce an additional deflecting internal wall (relative to the internal wall 27 forming the lateral channel 22) intended to be swept by the flowing fluid and to guide this fluid into the lateral channel 22.

[0055] In operation, the fluid is admitted into the conduit 23 and then into the side channel 22 at a relatively low pressure. Under the effect of the rotation of the rotor 4, the fluid circulates in the side channel 22 and performs a swirling movement around the insert 8 passing between the adjacent fins 42 of the rotor 4 (see). This swirling movement increases the pressure of the fluid throughout the flow in the side channel 22. The compressed fluid exits the side channel 22 through the discharge conduit 24.

[0056] The fluid machine 1 can also be used as an expansion turbine. In this configuration, the fluid is admitted into the conduit 23 and then into the side channel 22 at a relatively high pressure. The fluid pressure drives the rotor 4 to rotate. The fluid flows in a swirling motion around the insert 8, passing between the adjacent fins 42 of the rotor 4. This swirling motion gradually reduces the fluid pressure throughout the flow in the side channel 22. The expanded fluid exits the side channel 22 through the conduit 24.

Claims

Fluid machine (1) comprising a stator (2) and a rotor (4) rotatably mounted inside the stator (4), the stator (2) comprising a central zone (25) around which extends a lateral channel (22) intended for a flow of the fluid under the effect of a rotation of the rotor (4) or with a view to a rotation of the rotor (4), the lateral channel (22) being formed by an internal wall (27) of the stator 2 and having a first rim (22a) and a second rim (22b) between which extends a sealing dam (28), the stator (2) comprising an insert (8) which is arranged in the lateral channel (22) so as to form in the stator (2) an additional internal wall (81) intended to be swept by the flowing fluid, and to guide the fluid in the lateral channel (22), the rotor (4) comprising a wheel (41) provided with a plurality of peripheral fins (42), characterized in that the insert (8) is held in suspension in the lateral channel (22), so that,under the effect of the rotation of the rotor (4), the fluid circulates in the lateral channel (22) and performs a swirling movement around the insert (8) passing between adjacent fins (42) of the rotor (4)., Machine (1) according to the preceding claim, characterized in that the stator (2) comprises a suction duct (23) and a fluid discharge duct (24), the ducts (23, 24) each having one end in fluid communication with the lateral channel (22) and one end intended to be in communication with an external environment. Machine (1) according to the preceding claim, characterized in that the suction duct (23) opens into the lateral channel (22) at or near the first rim (22a), the discharge duct (24) opens into the lateral channel (22) at or near the second rim (22b). Machine (1) according to any one of the preceding claims, characterized in that the insert (8) is formed around the central zone (25) of the stator (2) and held in suspension in the lateral channel (22) by means of a support (9) of the stator (2). Machine (1) according to the preceding claim, characterized in that the support (9) is formed by the sealing dam (28), the insert (8) having a first end (82) and a second end (83) arranged on either side of the sealing dam (28). Machine (1) according to claim 4, characterized in that the support (9) comprises at least one tab (91, 92) which extends from the internal wall (27) forming the lateral channel (22), the insert (8) bearing on the at least one tab (91, 92). Machine (1) according to the preceding claim, characterized in that the at least one leg (91, 92) has an aerodynamic profile configured to facilitate the flow of fluid in the lateral channel (22). Machine (1) according to any one of claims 6 or 7 in combination with claim 5, characterized in that the support (9) comprises two legs (91, 92) positioned on either side of the sealing dam (28). Machine (1) according to any one of the preceding claims, characterized in that the lateral channel (22), respectively the insert (8), extends over an arc-shaped sector around the central part (25) of the stator (2) and has an arc length preferably between 290° and 350°. Machine (1) according to the preceding claim, characterized in that the lateral channel (22), respectively the insert (8), has in a vertical transverse plane a section in the form of a portion of a disc. Machine (1) according to the preceding claim, characterized in that the stator (2) comprises a lower part (2A) and an upper part (2B) assembled against each other, the lower part (2A) comprising the suction duct (23), the discharge duct (24) and the insert (8), the upper part (2B) comprising a housing (21) configured to receive the rotor (4). Machine (1) according to the preceding claim, characterized in that the wheel (41) rests on the central part (25) of the stator (2), the fins (42) being arranged projecting towards the lateral channel (22) and opposite the insert (8). Machine (1) according to any one of the preceding claims, characterized in that the machine (1) is a fan, a compressor or a pump.

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