JP2005248764A - Air bleeding system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent an engine form sucking high temperature bled air and thereby to prevent instability and drop in output of the engine caused, and to prevent an engine compression part from generating the bled air to be introduced to a front edge part of an engine intake and thereby to prevent less engine efficiency. <P>SOLUTION: In the air bleeding system S, compressed air is bled from the compression part 11 of an aircraft engine 1, and at least part of the bled air is introduced into an anti-icing bleeding line 4 which has an anti-icing heating part 42 positioned at the front edge part of the engine intake 2x, that is, a front edge part 2a of an engine nacelle 2, so that anti-icing is performed by heating the front edge part 2a of the engine nacelle. The bled air introduced into the anti-icing bleeding line 4 is introduced into an air-conditioning system AC at the next stage. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an extraction system that introduces at least a part of air extracted from a compression part of an aircraft engine into a front edge part of an engine intake and heats the front edge part of the engine nacelle to prevent ice.

In an aircraft having an engine such as a jet engine or a turboprop engine, if ice adheres to an engine intake which is an air introduction part for introducing air into the engine, for example, an air introduction part provided in a cowling part or a front end part of an engine nacelle The engine output can be reduced, or the engine can be damaged by sucking the peeled ice block. Accordingly, various engine intake anti-icing systems have been considered to prevent icing on the engine intake. As an example of such an engine intake anti-icing system, as schematically shown in FIG. 5, the anti-icing reaches the front edge b1 of the engine nacelle b which is the engine intake from the engine compression part through the anti-icing bleed introduction valve a. There is a so-called thermal anti-ice system in which bleed air is introduced into the bleed line c and the front edge b1 of the engine nacelle b is heated by bleed to prevent icing (see, for example, Patent Document 1).
JP-A-2-130225

  Thus, in an engine intake anti-icing system that employs a thermal anti-ice system in which the leading edge of the engine intake is heated by extraction, conventionally, the introduced extraction has been discharged to the outside as it is.

  However, with such a configuration, it has been unavoidable that problems such as instability of the engine and reduction in output due to the intake of high-temperature bleed air by the engine are unavoidable. Furthermore, since the bleed air to be introduced into the engine intake is disposable, the engine compression section has to create extra bleed air for this amount, and it has been unavoidable that the engine efficiency is reduced.

  In order to solve the above-described problems, the present invention constitutes an extraction system that extracts air from the compression portion of the engine and introduces it into the front end portion of the engine intake.

  That is, the extraction system according to the present invention extracts compressed air from a compression unit of an aircraft engine, and includes an anti-icing heating unit positioned at the front edge of the engine intake for at least part of the extracted extraction air. An bleed system that heats the leading edge of the engine intake to prevent ice by introducing it into the anti-ic bleed line, and introduces the bleed air introduced into the anti-ic bleed line into the next-stage air conditioning system It is characterized by.

  If this is the case, while the leading edge of the engine intake is heated by the bleed air introduced into the anti-icing heating part of the anti-icing bleed line, this bleed air is introduced into the next air conditioning system. It is possible to suppress problems that occur in a configuration in which conventional high-temperature and high-pressure compressed air is introduced into the front edge portion of the engine intake and discharged as it is, such as engine instability and output reduction due to intake of high-temperature bleed air by the engine. it can.

  In addition, it is possible to suppress a reduction in engine efficiency due to the generation of extra high-pressure air to be introduced into the front edge portion of the engine intake, thereby saving engine fuel consumption.

  Furthermore, a mode in which the extracted air extracted from the compression chamber of the engine is introduced into the air conditioning system through a precooler that is a heat exchanger having a function of reducing the temperature of the extracted air by heat exchange with the ram air is widely used. As a skin heat exchanger that reduces the temperature of the bleed air introduced into the anti-icing bleed line by exchanging heat with the front edge of the engine intake on the surface of the anti-icing heating unit if the configuration as described above is adopted. Therefore, the precooler can be downsized or omitted. In particular, if an embodiment in which the precooler is omitted is employed, engine fan air supplied to the precooler becomes unnecessary, and engine efficiency can be improved.

  In the present invention, the air conditioning system is a system that receives supply of extraction air from the extraction system, and adjusts temperature and pressure.

  According to the bleed system according to the present invention, the entire amount of the bleed air introduced into the anti-icing bleed line having the anti-icing heating part located at the front edge of the engine intake is introduced into the air conditioning system that controls the temperature and pressure of the bleed air. As a result, problems such as engine instability due to the intake of high-temperature bleed air by the engine can be solved.

  A first embodiment of the present invention will be described below with reference to the drawings.

  As shown in FIG. 1, the aircraft according to this embodiment, in order from the front, compresses the air taken from the front, and mixes and burns the air compressed by the compression unit 11 and fuel. An engine 1 having a combustion chamber 12 and a turbine section 13 that converts combustion energy generated in the combustion chamber 12 into aircraft propulsion and a substantially cylindrical engine nacelle 2 that covers the engine 1 are provided. Further, in this aircraft, the front end portion of the engine nacelle 2 is an engine intake 2x that is an air introduction portion, and air passes through the engine intake 2x and is taken into the compression portion 11 of the engine 1.

  Moreover, in this embodiment, it is located in the extraction system S which extracts the extraction which is compressed air from the compression part 11 of the engine 1, and this extraction system S in the pre-pressure chamber after adjusting the temperature and pressure of extraction. And an air conditioning system AC to be supplied. The extraction air has a higher temperature and a higher pressure than the outside air due to adiabatic compression in the compression section 11.

  Further, the extraction system S introduces a part of the extraction into the front edge portion of the engine intake 2x, that is, the front edge portion 2a of the engine nacelle 2, and heats the front edge portion 2a of the engine nacelle 2 by this extraction to prevent ice. It also functions as a thermal anti-ice engine intake anti-icing system.

  Specifically, the extraction system S branches from a main extraction line 3 that connects the compression unit 11 of the engine 1 and the air conditioning system AC, and an anti-icing extraction inlet 3a provided in the main extraction line 3. An anti-icing bleed line 4 that merges with the main bleed line 3 is provided at an anti-icing bleed air recirculation port 3b provided downstream of the anti-icing bleed inlet 3a.

  The main bleed line 3 is provided with a backflow prevention valve 31 for preventing the backflow of the bleed air at a portion upstream from the anti-icing bleed intake port 3a, and an air-conditioner is provided at a portion downstream from the anti-icing bleed air recirculation port 3b. A bleed pressure regulating valve 32 is arranged to prevent abnormal high temperature and high pressure air from flowing into the system AC. Further, a precooler 33 that cools the bleed air is disposed downstream of the bleed pressure regulating valve 32. The precooler 33 is also connected to the front edge 2a of the engine nacelle 2 via the ram air line 331, and performs heat exchange between the bleed air passing through the main bleed line 3 and the ram air introduced via the ram air line 331. In this way, the bleed air is cooled. The ram air line 331 is provided with a ram air valve 331a for adjusting the flow rate of the ram air.

  Thus, in the present embodiment, the anti-icing bleed line 4 is positioned at the introduction part 41 reaching the front edge 2a of the engine nacelle 2 from the anti-icing bleed intake 3a and the front edge 2a of the engine nacelle 2. The anti-icing heating unit 42 is configured to circulate in a loop, and the reflux unit 43 communicates with the anti-icing heating unit 42 and reaches the anti-icing bleed air reflux port 3b. The introduction portion 41 is provided with an anti-icing valve 44 that adjusts the amount of air introduced into the anti-icing bleed line 4. The bleed air introduced into the anti-icing bleed line 4 is configured such that substantially the entire amount is introduced from the anti-icing bleed air recirculation port 3b to the next-stage air conditioning system AC through the main bleed air line 3. The shape of the anti-icing heating unit 42 is shown in FIG.

  The air conditioning system AC has a configuration similar to that known as this type of aircraft air conditioning system, for example, the one described in Japanese Patent Application Laid-Open No. 11-44463.

  In the present embodiment, the extraction air that is high-temperature and high-pressure compressed air extracted from the compression unit 11 of the engine 1 flows as follows. First, the bleed air is introduced into the main bleed line 3. Next, a part of the bleed air is branched from the anti-icing bleed intake 3 a and introduced into the anti-icing bleed line 4. The bleed air introduced into the anti-icing bleed line 4 reaches the anti-icing heating unit 42 through the introducing unit 41. In the anti-icing heating unit 42, the bleed air circulates around the front edge 2a of the engine nacelle 2 and exchanges heat with this part. That is, the front edge portion 2a of the engine nacelle 2 is heated by extraction. Substantially the entire amount of the bleed air merges with the main bleed line 3 through the reflux portion 43 at the anti-icing bleed air reflux port 3b. On the other hand, the remainder of the bleed passes through the main bleed line 3 toward the anti-icing bleed air recirculation port 3b. The bleed air that has joined at the anti-icing bleed air recirculation port 3 b is introduced into the precooler 33 that is a heat exchanger that exchanges heat between the bleed air and the ram air via the bleed pressure regulating valve 32, and is cooled in the precooler 33. Then, the bleed air cooled in the precooler 33 is introduced into the air conditioning system AC, and is further supplied to the preload chamber after the temperature is adjusted and regulated in the air conditioning system AC.

  That is, the leading edge 2a of the engine nacelle 2 is heated by the bleed introduced into the anti-icing bleed line 4 to prevent the ice from adhering to this part. Further, since the temperature of the bleed air introduced into the anti-icing bleed line 4 is lowered by heat exchange with the front edge portion 2a of the engine nacelle 2, the temperature of the bleed air toward the precooler 33 is also lowered.

  As described above, when the anti-icing system S according to the present embodiment is employed, the leading edge 2a of the engine intake 2x, that is, the engine nacelle 2 is extracted by the bleed introduced into the anti-icing heating unit 42 of the anti-icing bleed line 4. While heating the leading edge 2a, substantially the entire amount of the bleed introduced into the anti-icing bleed line 4 is joined to the main bleed line 3 at the anti-icing bleed recirculation port 3b. It is possible to prevent the occurrence of problems such as instability and reduced output caused by inhaling air. In addition, when introducing the bleed air to the front edge of the engine nacelle and discharging it to the outside as it is, it is necessary to create an extra amount of bleed air that is discharged to the outside, resulting in a decrease in engine efficiency associated therewith, In the present embodiment, since almost the entire amount of the bleed air introduced into the anti-icing bleed line 4 and used to heat the front edge 2a of the engine nacelle 2 is joined to the main bleed line 3 and introduced into the air conditioning system AC. The occurrence of this problem can also be prevented.

  Further, as described above, the bleed air introduced into the anti-icing bleed line 4 is cooled by heat exchange with the front edge portion 2a of the engine nacelle 2, so that the precooler 33 can be downsized.

  Next, a second embodiment of the present invention will be described below with reference to the drawings. In addition, the same name and code | symbol are attached | subjected to the site | part corresponding to 1st Embodiment mentioned above.

  As shown in FIG. 3, the aircraft according to this embodiment, in order from the front, compresses the air taken from the front, and mixes and burns the air compressed by the compression unit 11 and fuel. An engine 1 having a combustion chamber 12 and a turbine section 13 that converts combustion energy generated in the combustion chamber 12 into aircraft propulsion and a substantially cylindrical engine nacelle 2 that covers the engine 1 are provided. Also in this aircraft, the front end portion of the engine nacelle 2 is an engine intake 2x that is an air introduction portion, and air passes through the engine intake 2x and is taken into the compression portion 11 of the engine 1.

  Further, in the present embodiment, the extraction system S that extracts the extraction air, which is high-temperature and high-pressure compressed air, from the compression unit 11 of the engine 1, and the extraction system S is located in the next stage of the extraction system S, and after adjusting the extraction temperature and pressure And an air conditioning system AC that supplies the preload chamber. The extraction air has a higher temperature and a higher pressure than the outside air due to adiabatic compression in the compression section 11.

  The bleed system S introduces substantially the entire amount of bleed air into the front edge portion of the engine intake 2x, that is, the front edge portion 2a of the engine nacelle 2 and heats the front edge portion 2a of the engine nacelle 2 to prevent ice. It also functions as a thermal anti-ice engine intake anti-icing system. Furthermore, it is configured such that substantially the entire amount of this bleed air is introduced into the next-stage air conditioning system AC.

  Specifically, the extraction system S includes a main extraction line 6 that reaches the air conditioning system AC from the compression unit 11 of the engine 1 via the front edge 2a of the engine nacelle 2.

  The main bleed line 6 includes an introduction part 61 that connects the compression part 11 of the engine 1 and the front edge part 2a of the engine nacelle 2, an anti-icing heating part 62 that is located at the front edge part 2a of the engine nacelle 2, A reflux portion 63 that connects the front edge 2a of the engine nacelle 2 and the air conditioning system AC is provided. The introduction part 61, the anti-icing heating part 62, and the reflux part 63 are all in communication. In addition, the anti-icing heating unit 62 is formed in a staggered pattern on the front edge 2a of the engine nacelle 2 as shown in FIG.

  Therefore, in the present embodiment, a configuration in which substantially the entire amount of the bleed air introduced into the main bleed line 6 is introduced into the air conditioning system AC through the introduction portion 61, the anti-icing heating portion 62, and the reflux portion 63. doing.

  The introduction portion 61 is provided with a backflow prevention valve 611 for preventing the backflow of extraction air, and an anti-icing valve for adjusting the amount of air introduced into the main extraction line 6 downstream of the backflow prevention valve 611. 612 is arranged. In addition, a bleed pressure regulating valve 631 is disposed in the recirculation unit 63 in order to prevent abnormal high temperature and high pressure air from flowing into the air conditioning system AC.

  The air conditioning system AC has a configuration similar to that known as this type of aircraft air conditioning system, for example, the one described in Japanese Patent Application Laid-Open No. 11-44463.

  In the engine 1 according to the present embodiment, the extraction air that is high-temperature and high-pressure compressed air extracted from the compression unit of the engine 1 flows as follows. First, substantially the entire amount of the bleed air is introduced into the introduction portion 61 of the main bleed line 6. Next, substantially the entire amount of the extracted air reaches the anti-icing heating unit 62. The bleed air that has reached the anti-icing heating unit 62 goes to the reflux unit 63 while exchanging heat with the front edge 2a of the engine nacelle 2. That is, the front edge 2a of the engine nacelle 2 is heated and the bleed air is cooled by the heat exchange. Then, substantially the entire amount of the cooled bleed air is introduced into the next-stage air conditioning system AC through the recirculation unit 63, and is supplied to the preload chamber after the temperature is adjusted and regulated in the air conditioning system AC. That is, in the present embodiment, the main ventilation line 6 also has a function as the anti-icing ventilation line 4 in the first embodiment described above.

  If the extraction system S according to the present embodiment is employed, the entire amount of extraction air introduced into the anti-icing heating unit 62 of the main extraction line 6 is introduced into the subsequent air conditioning system AC through the reflux unit 63. All the main effects in the extraction system S according to the first embodiment described above can be obtained.

  Further, in the present embodiment, since the anti-icing heating unit 62 is formed in a staggered pattern, the surface area of the anti-icing heating unit 62 is large, and accordingly, the leading edge 2a of the bleed air and the engine intake 2x, that is, the leading edge of the engine nacelle 2 The air can be supplied to the air conditioning system AC after the heat exchange with the section 2a is more completely performed and the temperature of the extraction air is sufficiently lowered. That is, by making this anti-icing heating unit 62 function as a skin heat exchanger that performs heat exchange between the bleed air and the front edge 2a of the engine nacelle 2, the precooler 33 in the first embodiment is omitted and the structure is simplified. Further, by omitting the precooler 33, the engine fan air supplied to the precooler 33 is not necessary, so that the engine efficiency can be further improved. Such an effect can also be obtained by, for example, the anti-icing heating unit 62 formed in a spiral shape around the front edge 2a of the engine nacelle 2.

  The present invention is not limited to the embodiment described above.

  For example, if the anti-icing heating part is located at the front edge of the engine nacelle and has a function as a heat exchanger for exchanging heat between the bleed air and the front edge of the engine nacelle, the shape thereof is arbitrary. May be set.

  Further, as long as at least a part of the bleed air introduced into the anti-icing bleed line having the anti-icing heating unit is configured to be introduced into the next-stage air conditioning system, the configuration of the bleed line of the bleed system is the above-described first and A configuration other than that described in the second embodiment may be employed.

  Further, in an aircraft in which an engine intake that is an air introduction portion is formed in a portion other than the front end portion of the engine nacelle, bleed air is introduced into an anti-icing bleed line having an anti-icing heating portion located at a front edge portion of the engine intake. Then, the front edge of the engine intake may be heated, and the bleed air introduced into the anti-icing bleed line may be introduced into the air conditioning system as the next stage.

  Even with such a configuration, since at least a part of the bleed air is introduced into the air conditioning system without being discharged, it is possible to suppress problems associated with the intake of high-temperature bleed air by the engine and to discharge it to the front edge of the engine intake. Therefore, it is possible to suppress a decrease in engine efficiency caused by generating extra bleed air for the purpose. Further, since the extraction air is cooled by heat exchange between the extraction air and the front edge portion of the engine intake, it is possible to reduce the size or omit the precooler.

  In addition, various changes may be made without departing from the spirit of the present invention.

Schematic which shows the extraction system which concerns on 1st Embodiment of this invention. Schematic which shows the anti-icing heating part of the anti-icing extraction line which concerns on the same embodiment. Schematic which shows the extraction system which concerns on 2nd Embodiment of this invention. Schematic which shows the anti-icing heating part of the anti-icing extraction line which concerns on the same embodiment. Schematic which shows the conventional extraction system.

Explanation of symbols

S ... Bleeding system AC ... Air conditioning system 1 ... Engine 11 ... Compression section 2 ... Engine nacelle 2x ... Engine intake 2a ... Front edge of engine nacelle 4 ... Anti-icing bleed line 6 ... Bleeding line (anti-icing bleed line)
42, 62 ... Anti-icing heating section

Claims (1)

By extracting compressed air from the compression part of an aircraft engine and introducing at least part of the extracted air, which is the extracted air, into an anti-icing extraction line having an anti-icing heating part located at the front edge of the engine intake A bleed system that heats a front edge of an engine intake and performs ice prevention, wherein the bleed air introduced into the anti-icing bleed line is introduced into a next-stage air conditioning system.

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