Particle separator for use with turbines.

Description: TECHNICAL FIELD [Detailed description of the invention]

Background of the invention The present invention generally relates to gas turbine engines, particularly devices installed in such engines to separate foreign particles from the airflow entering the engine. Gas turbine engines typically include an air intake that receives all the air that enters the engine and a compressor inlet that receives the air that enters the compressor. Each engine also includes an inner wall that defines the main flow path of air that travels from the air intake to the compressor inlet. It is known that a particle separator is provided at the inlet of the compressor to clean the foreign particles from the engine intake air in order to reduce the possibility of the engine sucking foreign particles such as sand or debris. Usually such a separator includes an annular partition or split lip properly installed with respect to the main flow path, and during the operation of the gas turbine, the air to be used in the compressor is along one side of the split lip. Guided and guided along the other side of the split rip for collection and removal of foreign matter particles carried by the air entering the air intake. Examples of such separators are described in US Pat. Nos. 3832086, 4265646 and 4527387. Conventional particle separators, such as those described in the US patent specification, have only a single annular inlet that receives foreign particles carried by the air that enters the air intake of the engine. It is known that conventional particle separators with a single inlet separate a significant portion of foreign particles from the intake air, but some particles, including many finer particles, are at the separator inlet. Could not be collected by the separator, bypassing or accumulating in the engine air passage. Bypassing or accumulating such particles accelerates the deterioration of internal engine components, shortens the service life of those components, and reduces engine performance. Accordingly, it is an object of the present invention to provide a new and advanced particle separator for gas turbine engines with improved ability to collect foreign particles carried by the airflow entering the air inlet of the engine. It is in. Another object of the present invention is to provide a particle separator particularly well suited for collecting relatively fine particles carried by air entering an engine. Another object of the present invention is to provide a particle separator that reduces the amount of foreign particles in the air stream that has entered the air intake of an engine. Another object of the present invention is to provide a particle separator that reduces the possibility of airflow separation in a particular area of intake airflow and reduces the pressure loss normally resulting from airflow separation. Another object of the present invention is to provide a particle separator designed to disrupt the mass transport mechanism that results in the inefficiency of particle separation. Another object of the present invention is to provide a particle separation device having no moving element, that is, a passive particle separating device so that the service life is relatively long. Another object of the present invention is to provide a particle separator that is relatively inexpensive, lightweight and works effectively. Abstract of the invention The particle separator for a gas turbine engine of the present invention is characterized by including a plurality of particle extraction passages. The gas turbine engine includes an air intake passage that receives air taken into the engine and an inner wall that defines a compressor inlet passage that communicates with the air intake passage. The particle separator has a main particle separator and an auxiliary particle separator. The main particle separator includes a main collection chamber inlet passage that communicates with an air intake passage formed by a pair of inner walls of the engine arranged to face each other. The auxiliary particle separator is provided in association with one of the inner walls of the engine and includes means for defining an auxiliary passage having an inlet opening communicating with the air intake passage. The collection chamber inlet of the main particle separator accepts some of the foreign matter particles carried by the air entering the air intake passage, while the auxiliary passage of the auxiliary particle separator receives another part of the foreign matter particles. Therefore, the multiple extraction passages constructed by the main collection chamber inlet passage and the auxiliary passage increase the engine's ability to separate foreign particles from its intake air. Description of Examples FIG. 1 shows a partial cross-sectional side view of a typical gas turbine engine 10 adopting the present invention. The engine 10 includes a casing 14 that extends approximately along the engine central axis 12 in the axial direction and has an open front end 16 and an opposite open rear end 18. Within the casing 14, high temperature engine elements including a compressor 20, a combustor 22, a high pressure turbine 24 and a low pressure turbine 26 are arranged, as is known to those skilled in the art. The compressor 20 and the high pressure turbine 24 are connected by a shaft 28, and the low pressure turbine 26 is connected to the main engine drive shaft 30. During the operation of the gas turbine engine 10, air enters the front end 16 of the casing 14 and then flows through the compressor 20 to the combustor 22, where it is mixed with fuel and burned. Combustion products from the combustor 22 pass through the high pressure turbine 24 and then through the low pressure turbine 26, where the gas expands and energy is extracted. The energy extracted by the high-pressure turbine 24 drives the compressor 20 via the shift 28, and the energy extracted by the low-pressure turbine 26 drives the main engine-driven chassis 30. The drive shaft 30 powers an energy consuming device such as a helicopter rotor (not shown). The combustion gas after exiting the low-pressure turbine is discharged from the engine 10 through the rear end 18 of the casing 14. According to the present invention, the engine 10 is provided with a particle separating device that separates foreign particles from the air flow entering the front end 16 of the casing 14 and prevents the separated particles from entering the compressor 20. Foreign matter particles once separated from the air flow are accumulated in the engine 10 and removed from the engine 10. In order to accumulate and / or remove the separated foreign matter particles, the engine 10 is provided with an appropriate passage network that is operationally communicative with the front end of the casing. Such aisle networks can take any of a number of forms according to the present invention. Accordingly, specific examples of such passages used within the engine 10 for the accumulation and / or removal of separated foreign particles will be described in detail, the description of which is to limit the form of the passages. Please understand that it is not a thing. In FIG. 1, casing 14 has an annular inner wall 32 that extends rearward from the front end 16 to the annular cavity 34 and faces inward in the radial direction. Further, the casing 14 is provided with a passage 36 through which the passage 36 is generally L-shaped, one leg 38 opening along the inner wall 34 of the casing and the other leg 40. Opens out of the casing 14 at a position radially outside the cavity 34. The engine 10 further includes a hub 42 that supports the compressor 20, the combustor 22, and the turbines 24, 26 within the casing 14. The hub 42 is located entirely in the center of the casing 14 and includes a body 48 having a bow-shaped outer wall 44. The outer wall 44 extends in the axial direction of the engine 10 between the front end 16 of the engine 10 and the compressor 20 and faces the inner wall 32 of the casing 14 as a whole. The wall 32 of these casings and the wall 44 of the hub together constitute an annular air intake passage 46 that receives engine intake air. The hub wall 44 has a contour that defines the outermost radial ridge 44a with the largest diameter, so that a narrow throat with the smallest annular area is formed in the air intake passage 46. .. In FIGS. 1 and 2, the hub body 48 further includes a substantially annular passage 50 extending from an inlet or opening 52 located radially outward to an annular internal cavity 54 located radially inward. The aisle 50 is formed by interstitial wall members 56a and 56b supported within the hub body 48, the opening 52 of which is generally arranged to open upstream into the air intake aisle 46. There is. The hub body 48 further includes an opening 60 provided in the wall 44, and a wall member 56b is arranged inside the hub body 48 to define a passage 58 extending between the passage 50 and the opening 60. The hub 42 is supported within the casing 14 by a number of radial struts 62 (only one is shown in FIGS. 1 and 2). The single strut 62 illustrated in FIGS. 1 and 2 is hollow and includes a radial passage 64 that connects the passage 58 in the hub to the passage 36 in the casing. As will be described in detail later, the passage 50 is designed to receive foreign particles in the air entering the air intake passage 46, and the passages 58, 64 and 36 communicating with the passage 50 form a conduit 66 as a whole. Then, the particles received in the passage 50 are removed from the engine 10. With reference to FIG. 1 again, the engine 10 includes means of forming a first partition, generally represented by reference numeral 68, joined to the casing 14. Partition 68 is of the form of a split rip 70 with an upstreamly oriented tip 72, supported by casing 14 in the figure, but instead by hub 42 or another structure. You can also do it. As well shown in FIG. 2, the split rip 70 contains two totally concentric parts 74 and 76 that make up the facing inner walls 82 and 84, respectively, with the inner walls 82 and 84 interspersed. It is separated by 78 and supported by a plurality of circumferentially spaced stanchions or vanes 80. Concentrically arranged portions 74 and 76 are contoured to form a split rip 70 with a streamlined cross-sectional shape as a whole, and extend radially inwardly and radially outward of the split rip 70. Define the facing wall 81. As shown in FIGS. 1 and 2, the radial inner wall 83 of the split lip 70 is generally with a portion of the outer wall 44 of the hub 42 located in front of and adjacent to the compressor 20. I'm facing you. Therefore, the wall 83 of the split lip and the wall 44 of the hub together define an annular compressor inlet passage 86 for guiding air to the compressor 20. Further, as shown in FIG. 2, the air intake passage 46 and the compressor inlet passage 86 as a whole are the main airflow for moving the air into the engine 10 toward the compressor as shown by the arrow 88. Form a road. The main air flow path outlined in the form of an arrow 88 is an overall radial inward angle with respect to the first portion 90, which is generally parallel to the central axis 12 of the engine, and the first portion 90. It includes two parts 92 and a third part 94 that is totally parallel to the engine center axis 12. Further, the main air flow path 88 of the air flowing from the air intake passage 46 of the engine is formed between the first part 90 and the second part 92 by the first bending part and the second part 92 indicated by reference numeral 96. Includes a second curved portion, indicated by reference numeral 98, between the third portion 94 and the third portion 94. Furthermore, the main air flow path 88 includes facing radial inner side surfaces 88a and outer side surfaces 88b, respectively. For ease of understanding, these sides 88a and 88b are shown as the sides of arrow 88 in FIG. 2 provided at the center of the air intake passage 46 and the compressor inlet passage 86, but the side 88a And 88b represent the corresponding parts of the hub wall 44 and the casing wall 32 or the split rip wall 83, respectively. The engine 10 also includes means of constructing a second partition as a whole, indicated by reference numeral 100, which is a plurality of circumferences between the wall 32 of the casing 14 and the radial outer portion 76 of the split lip. It is supported by vanes 85 and 87 that are spaced apart in the direction. The partition 100 is in the form of an annular partition or diversion plate 102 having a radial outer wall 104 and a radial inner wall 106 extending rearward from the tip 108. The walls 104 and 106 of the diversion plate are contoured to form a diversion plate 102 having a relatively streamlined cross section. In the relatively harsh environment in which the engine 10 is operated, the air entering the air intake passage 46 may contain foreign particles such as sand or debris, so the engine 10 is further generally indicated by reference numeral 110. Includes particle separator. The particle separator has an increased ability to clean or separate foreign particles from the airflow entering the air intake passage according to the present invention. The particle separator 110, as described with reference to FIG. 2, has a main particle separator 112 and at least one auxiliary particle separator to clean foreign particles in the air that have entered the air intake passage 46. The illustrated engine 10 is provided with first, second and third auxiliary particle separators 114, 116 and 118, which separate foreign particles in the intake air that were not collected by the main particle separator 112. And relatively clean the air entering the compressor. In FIGS. 1 and 2, the main particle separator 112 includes a separation means 120 for separating foreign particles from the air moving in the air intake passage 46, a cleaning air passage 122 for guiding the separated foreign particles, and a passage. Includes removal means 124 to remove particles separated from 122. In the engine 10, the convenience means 120 is configured by the split rip 70. The split rip 70 allows foreign particles in the air moving through the air intake passage 46 to pass through one side of the split rip 70 and the air to be used by the compressor 20 to pass through the other side of the split rip 70. It is arranged with respect to the main air flow path of the relationship. More specifically, in FIG. 2, when the intake air is guided to the vicinity of the first curved portion 96 of the main air flow path 88, the operating amount of the foreign matter particles carried by the intake air causes the particles to be driven by the engine 10. It keeps moving in the axial direction of the particle, so that the particle is located radially outside the split lip 70. Therefore, the particles located radially outside the split lip 70 are separated from the air entering the compressor inlet passage 86 by the split lip 70. The separated particles are carried by a part of the inlet flow to an external discharge position away from the compressor inlet. The cleaning air passage 122 of the main particle separator 112 is configured by the annular cavity 34 in the form of a scroll-type collection chamber known to those skilled in the art. The cleaning air passage 122 communicates with the air intake passage 46 through the space formed between the part 76 of the split lip 70 and the diversion plate 102, and this space is for the cleaning air passage of the main particle separator 112. It constitutes the passage entrance 126. The space defined between the split lip portion 76 and the diversion plate 102 further constitutes a passage portion 144 adjacent to the passage entrance 126. The portion referred to as the main cleaning flow portion in the main air flow path 88 indicated by reference numeral 126a in FIG. 2 crosses the passage inlet 126 during the operation of the engine 10. The passage portion 144 is arranged at an acute angle B of, for example, 30 ° with respect to the passage portion 126a. In such a relationship, the passage portion 144 is positioned within the line of the axial momentum of the foreign particles, and the intake air flowing along the main air passage 88 and the particles in the passage portion 144 are received by the passage portion 144. Make it easier. The removing means 124 of the main particle separator 112 includes a guiding device 128 coupled to communicate with the cleaning air passage 122 through the opening of the casing 14 to guide the cleaning flow. The guidance device 128 can be a blower, an ejector or other device that guides the flow. In action, the induction device 128 draws the particles trapped in the passage 122 with the cleaning air and discharges them to the atmosphere through the pipe 130. According to an embodiment of the invention, the auxiliary particle separator 114,116 or 118 is provided in association with the internal wall 32,44 or 83 of each engine 10 and along or along the corresponding wall 32,44 or 83. It accepts particles entrained in an air stream that flows close to it. For this reason, each of the auxiliary particle separators 114, 116 and 118 was separated from the inlet opening communicating with the air intake passage 46, the cleaning air passage leading the separated particles received by this inlet opening, and the engine 10. Includes means for removing particles. With reference to FIGS. 1 and 2, the first auxiliary particle separator 114 of the engine 10 has an opening 52 made in the wall 44 as an inlet to receive foreign particles moving along the wall 44 of the hub. Includes said passage 50. As is well shown in FIG. 2, the opening 52 is provided on the wall 44 of the hub at the throat 132, which has the smallest annular area of the throat 132. As described above, the facing wall members 56a and 56b of the passage 50 are arranged so that the opening 52 of the passage entrance faces the front of the engine as a whole and faces the upstream of the main air flow path 88 as a whole. Has been done. Further, as is well shown in FIG. 2, the passage 50 has a portion 134 adjacent to the opening 52, which portion 134 is overall with respect to the portion 52A in the main air flow path 88 across the opening 52. Is oriented at an acute angle C of, for example, 10 ° or less. Such an angular relationship of the passage portion 134 and an overall upstream arrangement of the passage entrance opening 52 facilitates the operation of air passing through the opening 52 and foreign particles therein, and thus the opening 52 allows the air and the opening 52 to operate. It is considered that foreign matter particles are easily accepted. The auxiliary particle separator 114 further includes an auxiliary cleaning passage 136 connected in communication with the passage 50 to collect particles received through the opening 52. In the engine 10, the auxiliary cleaning passage 136 is composed of a cavity 54 formed in the hub body 48. The auxiliary particle separator 114 further includes a removing means 138 that removes the captured particles with an auxiliary cleaning stream. In engine 10, removal means 138 includes a guidance device 140 that communicates with the legs 40 of the passage 36 in the casing to guide the auxiliary cleaning stream. In action, the induction device 140 draws air from the air intake passage 46 through the hub passage 50, the cleaning passage 136, the strut passage 64, and the casing passage 36, and discharges the air to the atmosphere through the discharge pipe 142. The amount of air extracted by the auxiliary particle separator 114 from the airflow moving through the air intake passage 46 can be, for example, properly adjusted for the power supplied to the induction device 140 or doubled in the passage 50 (figure). It can be controlled by attaching (not shown) or the like. The guidance device 140 may be the same as or different from the guidance device 128 used to guide the main cleaning stream. The auxiliary particle separator 114 has the advantage of facilitating the collection of foreign particles entrained in the intake airflow portion adjacent to the hub wall 44, including the boundary layer. Foreign particles carried by the intake air often contain coarse sand and / or very fine dust, so such particles remain in the intake air portion that flows adjacent to the hub wall 44. Therefore, it is easily sucked into the compressor 20, the combustor 22, the turbines 224 and 26, and other internal devices or passages. If such particles enter the engine, they will wear the internal elements, deposit on the internal surface, or clog the internal cavities, resulting in deterioration and performance degradation of the engine elements. In action, the first auxiliary particle separator 114 draws air flowing along the hub wall 44 through the opening 52. It is believed that constant extraction of air through the opening 52 facilitates the capture of slow-moving particles and / or fine particles that would not be collected if air were not extracted from the hub wall 44. These particles have insufficient momentum to reach the main particle separator 112 and easily enter the compressor 30 through the compressor inlet 86. By providing the auxiliary particle separator, such particles are drawn through the opening 52 and separated from the intake air moving toward the compressor 20. Therefore, the auxiliary particle separator 114 is a relatively fine particle and a slow large particle present in the air moving along the wall 44 of the hub, both of which are insufficient to be collected at other positions. It is particularly suitable for separating these particles, which have only momentum. In FIGS. 1 and 2, the second auxiliary particle separator 116 of the engine 10 is provided by an annular space 78 defined between concentric portions 74 and 76 of the split lip 70. Includes the formed passage 146. As is often shown in FIG. 2, the passage 146 in the split rip has an inlet 148 that opens close to the tip 72 and out of the radial outer wall 81 of the split rip 70, and has an inlet 148. It includes a portion 150 adjacent to the inlet 148 arranged at an acute angle D of, for example, 25 ° overall with respect to the portion 148a of the main air passage 88 (Fig. 2) flowing across. Passage 146 facilitates the acceptance of air and foreign particles in it. The split rip aisle 146 further has an outlet 152 communicating with the cleaning air passage 122 between the downstream ends of the split rip walls 82 and 84. The auxiliary cleaning air passage of the auxiliary particle separator is configured by the main cleaning air passage 122 described above, so that particles entering the passage 146 through the inlet 148 pass through the passage 122. Further, the removing means for removing the particles collected in the passage 122 by the passage 146 is composed of an induction device or 128. In action, the induction device 128 draws engine intake air through passages 146 and 122 and discharges it into the atmosphere through discharge pipe 130. The amount of air extracted by the auxiliary particle separator 116 from the airflow moving in the engine 10 is, for example, properly adjusted the induction device 128, or a cross (not shown) in the passage 146 of the split lip. It can be controlled by arranging. Instead of the above, a cleaning passage and / or guidance device independent of the main particle separator 112 can be used. The auxiliary particle separator 116 has an advantage that the passage 146 accepts foreign particles including particles that have not been captured by the main particle separator 112 due to an action such as rebound. It is believed that such additional particles are concentrated around the split lip 70, resulting in being drawn into the separator passage 146. Another advantage gained by the second auxiliary particle separator 116 is that it functions on the action of the local flow field around the split rip 70 and has any passage equivalent to the split rip passage 146. It can be easily understood by considering the effect of a similar flow field in the case of a split lip 70 having a normal smooth surface as if it were not. Typically, the amount of air sucked into the inlet of the divider is much less (ie less than 20%) than the amount of air entering the compressor inlet passage. Therefore, the air moving along the compressor inlet side of the split lip moves much faster than the air moving along the separator side of the split lip. At least in part, the acceleration of the air moving around the rip due to the difference in air velocities moving on both sides of the split rip causes the air flow around the split rip to separate from the wall near its tip. (Ie, the flow is not kept attached). Such flow separation is known to result in undesired pressure loss in the airflow flowing across the split lip towards the compressor. On the other hand, the second auxiliary particle separator 116 improves the flow pattern around the split rip 70 to reduce the possibility of flow separation near the tip 72 of the split rip 70. Such an improvement is thought to be due to the extraction of air through the passage inlet 148 by the auxiliary particle separator 116 and guiding it to flow along the wall 84 of the split lip, thus extracting and guiding the air. It is considered that the acceleration of the air around the tip 72 is suppressed by doing so. As a result, the air flow near the split lip 70 is less likely to separate, and the pressure loss of the main air flow that once flows through the split lip 70 toward the compressor 20 is effectively reduced. It is advantageous in engine design that the provision of the passage 146 reduces the pressure loss of the air flowing around the split lip 70. In particular, since it is considered that the split rip 70 having the passage 146 inside reduces the pressure loss of the main air flow as compared with the conventional normal split rip, the split rip 70 is equipped with the normal split rip in the casing 14. It can be installed in a position in front of the position. With such an attachment, the particle collection efficiency of the main particle separator can be increased while keeping the pressure loss of the airflow around the split lip 70 within a predetermined level or acceptable level. In FIGS. 1 and 2, the third auxiliary particle separator 118 of the engine 10 provides a passage 154 defined between the inner wall 32 of the casing and the radial outer wall 104 of the diversion plate 102. Including. The passage 154 has an upstream-facing inlet 156 that receives foreign particles and a downstream-facing outlet 157 that communicates with the cleaning air passage 122. The cleaning air passage associated with the third auxiliary particle separator 118 can be the same cleaning air passage 122 associated with the second auxiliary particle separator 116 and also removes particles collected from the passage 122. Guidance device 128 is used as the means. In action, the induction device 128 draws some air from the engine intake air through passages 154 and 122 and expels it into the atmosphere. Control of the air flow extracted from the intake air through the aisle 154 can be achieved, for example, by appropriately adjusting the induction device 128 or by arranging a cross (not shown) in the aisle 154. As is also well shown in FIG. 2, the passage 154 has a portion 158 adjacent to the inlet 156, which portion 158 is the code 52a of the main air passage 88 moving across the inlet 156. Or, it is oriented so as to form an acute angle E of, for example, 10 ° or less as a whole with respect to the axial portion shown in 90). It is believed that this orientation facilitates the acceptance of air directed towards the inlet 156, and as a result, facilitates the acceptance of foreign particles carried by the air entering the inlet 156. The third auxiliary particle separator 118 moves along the wall 32, especially adjacent to the wall 32 of the casing, because one wall of the passage 154 is formed by a portion of the wall 32 of the casing. It is considered suitable for extracting air from air. Therefore, the third auxiliary particle separator 118 collects foreign particles carried by a relatively high speed air flow along the wall 32 of the casing. The third auxiliary particle separator 118 is also advantageous with respect to the separation of the flow along the wall 32 of the casing of the engine 10. Since the air moving along the main air flow path 88 (Fig. 2) is fast, the flow may separate along the wall 32 of the casing downstream of which part 132 of the air intake passage 46. It has been known. Such delamination is due, at least in part, to the instability of air rapidly expanding or diffusing as the flow cross-sectional area downstream of the throat 132 increases. As a result of such flow separation, unstable separation flow areas are created, and foreign matter particles trapped in these separation flow areas are thrown into the main air flow, for example, to the center of the main air flow for cleaning. It will enter the compressor without being done. A third auxiliary particle separator 118, including passage 154, is believed to reduce the likelihood of flow separation along the casing wall 32. The reduction of such flow separation is at least partially desired to provide a diversion plate 102 between the split lip 70 and the casing wall 32, i.e., thereby allowing air to flow along the casing wall 32. It is considered that this is due to the extraction of the casing or a predetermined amount. Therefore, by dividing the flow section by the diversion plate 102 and adjusting the amount of air extracted or drawn from that one section area, the possibility of flow separation along the casing wall 32 is significantly reduced. In addition, the diversion plate 102 and vane 87 should form an additional blocking that reduces the flow area while ensuring that the surfaces do not angle the collision particles in an undesired direction. Can be done. This reduction in flow area helps reduce the tendency of flow separation. Further, the tendency of flow separation along the wall 32 of the casing is reduced by the passage 154, so that the pressure loss of the air flow moving around the first curved portion 96 (FIG. 2) of the main air flow path 88 is reduced. To do. The third auxiliary particle separator 118 provides another advantage of destroying the mass transport mechanism that makes sand separation inefficient. Such a mass transport mechanism is due to a high degree of turbulence of air moving through the air intake passage 46, in a manner that guides the air in a vortex and changes its state over time in various regions of the flow. Try to get it back. Therefore, when the promoted particles are carried into such an area to the inlet of the engine main particle separator, the vortex action of the air causes the particles to be carried back out from the separator inlet and the particles are separated. Enter the compressor without being collected in the vessel. In contrast, passage 154 of the third auxiliary particle separator 118 constitutes a clearly limited and relatively narrow passage that air entering its inlet 156 should follow as it moves toward the cleaning air passage 122. .. This limited passage 154 stabilizes the flow and significantly prevents the eddying action of air entering the inlet 156, which may act to return particles from the inlet 156 to the main air passage 88. As is clear from the above description, the inlets 52,148,156 of the auxiliary particle separators 114,116,118 and the inlets 126 of the main particle separator 112 are installed inside 88a or outside 88b of the main air flow path 88. It is considered that such an arrangement of the inlets deviated from the center of the main air flow path 88 does not significantly increase the pressure loss of the air flow flowing in the engine 10 at any of the inlets 52, 126, 148 or 156. Further, the passage 52,126,148 or 156 can reduce the engine pressure loss to the extent that the inlet 52,126,148 or 156 reduces the possibility of airflow separation. In addition, as mentioned earlier in connection with the second auxiliary particle separator 116, some to the extent that each of the particle separator inlets 52, 126, 148 or 156 disrupts the pattern of airflow adjacent to each inlet. The engine design change can be made to reduce or reduce the pressure loss of the air flow moving toward the compressor 20 to a predetermined value, or to further improve the particle collection efficiency of the particle separator 110. Such design changes include changing the dimensions of the particle separator inlets 52,126,148,156, changing the position of the split rip relative to the main air flow path 88, changing the shape of the walls 32,44,82,84 inside the engine, and scrolling vanes. Includes 80 focus adjustments, or appropriate changes to achieve uniform cleaning air extraction through separator inlets 52,126,156. Next, with reference to FIG. 3, a gas turbine engine 160 including a particle separator according to another embodiment of the present invention is shown in a simplified manner. The engine 160 includes a casing 164 with a wall 166, a hub 168 with a wall 170, and a split lip 172 with a radial inner wall 174 and a radial outer wall 176. The casing wall 166 and the hub wall 170 form an engine air intake passage 178 as a whole, and a throat portion 170a is formed in this passage. Similarly, the split rip wall 174 and the hub wall 170 form an overall compressor inlet passage 180, and the split rip wall 176 and casing wall 166 overall clean the main particle separator 184. It forms an inlet passage 182 with respect to the air passage. According to the present invention, the engine 160 includes, in addition to the main particle separator 184, a particle separator 162 having at least one auxiliary particle separator. The engine 160 is provided with six auxiliary particle separators, each with passages 190, 192, 194, 196, 198 and 200, as shown in FIG. Three passages 190, 192 and 194 open into the hub wall 170, two of which open at a defined location upstream of the throat 170a of the air intake passage 178, the remaining one. The two passages 194 are open downstream of the throat 170a of the air intake passage 178, that is, at a defined position within the compressor inlet passage 180. Two passages 196 and 198 are provided in the split rip 172, one of which opens near the immediate downstream of the tip 202 and the other passage 198 opens further away from the tip 202. doing. The last one passage 200 opens into the casing wall 166 at a position around the throat 170a. In action, passages 190, 192, 194, 196 and 200 receive intake air portions that flow adjacent to their respective walls, and thus receive foreign particles carried by the received air. The associated removing means for removing the particles collected by the particle separating device 162 may be any removing means known to those of skill in the art, including blowers or ejectors. The removal means is coupled to communicate with the separator passages 190,192,194,196,198 and 200. Therefore, the passage of the auxiliary particle separator according to the present invention can be opened at any number of positions along the inner wall of the engine. Next, FIG. 4 shows an engine 204 including a separator according to another embodiment of the present invention. The engine 204 includes a casing 206 with a radial inner wall 208, a hub 210 with a radial outer wall 212, and a split lip 214 with a radial inner wall 216 and a radial outer wall 218. Overall, the casing wall 208 and the hub wall 212 form the air intake passage 220 of the engine 204. Similarly, the wall 216 of the split lip and the wall 212 of the hub form a compressor inlet passage 222. In addition, a number of annular dividers or diversion plates 226,228,230 and 232 are operably mounted at intervals between the casing wall 208 and the split lip wall 218, as shown in FIG. According to the present invention, the engine 204 has a large number of passages 236,238,240,242 and 244 to receive foreign particles carried by the intake air moving towards the compressor inlet passage 222, as shown in FIG. Includes particle separator 224. The passage 236 is composed of an annular slot formed between the dividing lip wall 218 and the diversion plate 226, and the passage 238 is composed of an annular slot formed between the diversion plates 226 and 228. The passage 240 is composed of an annular slot formed between the diversion plates 228 and 230, and the passage 242 is composed of an annular slot formed between the diversion plates 230 and 232. The passage 244 is composed of an annular slot formed between the diversion plate 232 and the wall 208 of the casing. As shown in FIG. 4, each of the passages 236, 238, 240 and 244 communicates with the cleaning air passage 234 formed in the casing 206. During the operation of the engine 204, passages 236,238,240,242 and 244 receive intake air moving along the casing wall 208 in the air intake passage 220 and are therefore trapped in the intake air. Accept particles. Particles collected in the collection chamber or passage 234 through passages 236,238,240,242 and 244 can be removed from it by a suitable removal means 246 such as a blower or digita. Like the diversion plate 102 of the engine 10 in FIGS. 1 and 2, the diversion plates 226,228,230 and 232 of FIG. 4 reduce the possibility of flow separation along the casing wall 208 and inefficient particle separation. Destroy the mass transport mechanism. On the other hand, the diversion plate 226,228,230,232 of the engine 204 in Fig. 4 shall be used in place of the diversion plate 102 in the engines shown in FIGS. 1 and 2 in order to effectively utilize the selected area of the intake air flow. Can be done. In either case, the airflow through the separator passages formed by the casing walls, diversion plates and split rips is balanced to allow the airflow traveling through the engine to have acceptable properties or patterns. It is desirable that the air is removed. Although various embodiments of the particle separator of the present invention have been described above, it is clear to those skilled in the art that other modifications can be made, and thus fall within the true spirit and scope of the present invention. Such modifications are within the scope of the claims. For example, the particle separators in FIGS. 1 to 4 are for an annular or axially symmetric engine, but the particle separator according to the invention can also be used in engines with non-axisymmetric air intake passages. Can be used. Further, the present invention can be used in an engine having either an axial flow or a vortex type separator and can be integrated within a movable engine element and within an immovable engine element or airframe / equipment. Further, in the examples of the particle separators of FIGS. 1 to 4, at least four annular separator passages are provided for collecting foreign particles, but the particle separator according to the present invention has a smaller number. A passage, for example, two passages may be provided. Furthermore, one passage of the particle separator can be associated with or integrated with the collection and removal means of the other passage. For example, separate blowers may be provided for the two passages of the particle separator, or a single common blower may be provided to remove the collected particles. In addition, a single common cleaning air passage system may be provided for the two passages of the particle separator, or separate cleaning air passage systems may be provided. Therefore, the above-described embodiment is for illustration purposes only, and is not intended to limit the present invention to it.

[Simple explanation of drawings]

FIG. 1 is a partial cross-sectional side view of a gas turbine engine including a particle separator according to the present invention. Fig. 2 is an enlarged view of a part of Fig. 1. FIG. 3 is a simplified side sectional view of a part of a gas turbine engine including another particle separator according to the present invention. FIG. 4 is a simplified side sectional view of a part of a gas turbine engine including yet another particle separator according to the present invention. [Explanation of main codes], 32: Casing 14 wall, 44: Hub 42 wall, 46: Air intake passage, 86: Compressor inlet passage, 88: Main air passage, 112: Main particle separator, 114,116,118: Auxiliary particle separator, 50,144,146,154: Particle separator inlet passage, 70: Split rip, 102: Divergence plate, 122: Cleaning air passage, 124,138: Removal means.