WO2013067886A1

WO2013067886A1 - Refrigeration system for aircraft

Info

Publication number: WO2013067886A1
Application number: PCT/CN2012/083361
Authority: WO
Inventors: 况薇; 南国鹏; 简夕忠
Original assignee: 中国商用飞机有限责任公司; 中国商用飞机有限责任公司上海飞机设计研究院
Priority date: 2011-11-08
Filing date: 2012-10-23
Publication date: 2013-05-16
Also published as: CN102506514A

Abstract

A refrigeration system (200) for aircraft is provided, which includes: a first stage heat exchanger (102) for receiving hot bleed air from an engine; a second stage heat exchanger (106) with an inlet communicated with an outlet of the first stage heat exchanger (102) and an outlet communicated with an inlet of a mixing chamber; a valve (204) is arranged between the outlet of the second stage heat exchanger (106) and the inlet of the mixing chamber; sensors (210, 212) senses at least the temperature of environment air; and a controller (120) receives parameter from the sensors (210, 212) which are compared with a stored preset range, if the parameter is within the preset range, the controller (120) opens the valve (204), and the hot bleed air enters into the mixing chamber after passing through the first stage heat exchanger (102), the second stage heat exchanger (106) and the valve (204) in order. The refrigeration system (200) can save energy and improve economic performance.

Description

Refrigerator system for aircraft

The present invention relates to a refrigeration system, and more particularly to a refrigeration system for an aircraft. Background technique

The refrigeration system is the core component of the air conditioning of the aircraft cabin. At present, air circulation refrigeration systems are used on most passenger aircraft, and the three-wheel air circulation refrigeration system is particularly popular on mainstream trunk passenger aircraft.

As shown in FIG. 1, the refrigeration system 100 includes a first stage heat exchanger 102, a compressor 104, a second stage heat exchanger 106, a regenerator 108, a condenser 110, a water separator 1 12, and a turbine 1 14 , flow control valve 116, ram air conditioning valve 1 17, temperature control valve 1 18 and so on. Wherein, one end of the first stage heat exchanger 102 is for receiving the hot bleed air from the flow control valve 116, and the other end is connected to the intake end of the compressor 104 and the temperature control valve 186, respectively. The outlet end of the compressor 104 is in communication with the inlet end of the second stage heat exchanger 106, and the outlet end of the second stage heat exchanger 106 is connected to the regenerator 108. The regenerator 108, the condenser 110 and the water separator 112 are sequentially connected to form a one-way fluid circulation loop, and the regenerator 108 and the condenser 110 are also connected to the inlet of the turbine 114 and the outlet of the turbine 114, respectively. The aforementioned temperature control valve 18 is also connected to the outlet of the turbine 1 14 such that air passing through a one-way fluid circulation enters the turbine 114 and again enters the condenser 110 to pass into the mixing chamber. In order to control the flow control valve 116, the ram air regulating valve 1 17 and the temperature control valve 1 18 described above, the refrigeration system 100 further includes a controller 120 and a temperature sensor 122. Wherein, the controller 120 can control the state of the flow control valve 116, the ram air regulating valve 117 and the temperature control valve 118, such as opening (including the degree of opening of the valve) and closing, and the temperature sensor 122 is disposed in, for example, a mixing chamber or a cockpit. The temperature value is transmitted to the controller 120, and the controller 120 controls the temperature control valve 1 18 according to the received temperature value.

Hereinafter, the cooling will be described by the flow path diagram of the refrigeration system 100 shown in FIG. The principle of system 100.

First, the hot bleed air (or auxiliary power unit APU) of the engine is regulated by the flow control valve 116 under the control of the controller 120, and enters the first stage heat exchanger 102 for cooling; then, after cooling The gas enters the compressor 104 and is compressed into a high temperature and high pressure gas; then, the high temperature and high pressure gas that exits enters the second stage heat exchanger 106 for cooling. The air flowing out of the second stage heat exchanger 106 enters the regenerator 108 and enters the condenser 110, so that the temperature of the air continues to decrease below the dew point temperature and the wet air is formed with free water. Then, the above-described wet air in which free water is formed enters the water separator 1 12, and most of the free water is removed in the water separator 12 12 . As shown in Fig. 1, the air from the water separator 1 12 is returned to the regenerator 108 again, and at this time, even if there is no separated moisture, it is evaporated again in the regenerator 108. Subsequently, the dehydrated dry air enters the turbine 114, and after the expansion of the turbine 1 14 is cooled, the temperature is further lowered, and then, through the condenser 110, is input into the mixing chamber. The cryogenic air-intake air distribution system then provides conditioned fresh air to the cockpit.

The cold sources of the first stage heat exchanger 102 and the second stage heat exchanger 106 are both ram air flowing through the punching passage, which is adjusted by the ram air regulating valve 117, which is generally one. Alternatively, it may be disposed at the intake end of the cold source of the second stage heat exchanger 106, or may be disposed at the outlet end of the cold source of the first stage heat exchanger 102. When flying at high altitude, the ram air is cold outside air, and when it is on the ground, it can be sucked by a fan 119 provided in the ram lane to introduce air as a cold source.

In the condenser 110, the higher temperature air flowing from the second stage heat exchanger 106 and entering the condenser 110 acts as a heat source, and the temperature flowing from the turbine 1 14 to the condenser 1 10 is higher. Low air is used as a source of cold. Thus, not only can a small amount of moisture or ice condensed at the outlet of the turbine 114 be warmed, melted and evaporated, but also a dry and cooler air can be supplied to the mixing chamber.

In addition, when the temperature control valve 118 disposed between the first stage heat exchanger 102 and the turbine 1 14 outlet is opened, the hot bleed air is output to the turbine 1 14 outlet through the first stage heat exchanger 102 and then through the condenser 1 10 output into the mixing chamber to adjust the temperature in the mixing chamber Degree.

However, the optimized use of engine bleed air under certain conditions is not considered in such conventional refrigeration systems. For example, when the bleed air pressure of the refrigeration system 100 is too low, and the bleed air does not achieve effective expansion cooling through various devices to meet the temperature requirements of the mixing chamber or the cockpit, the bleed air system usually switches. The bleed air is supplied to the high pressure stage of the engine compressor to meet the pressure requirements of the refrigeration system. However, such a refrigeration system that switches to a high pressure stage for bleed air reduces both the efficiency of the engine and the economy of the refrigeration system. Summary of the invention

In order to make rational use of engine bleed air and increase the economics of the refrigeration system, the present invention has been improved and optimized on the basis of the conventional refrigeration system, and the operation mode of the refrigeration system under specific conditions, that is, the economic mode, has been increased. It is achieved by adding valves and corresponding piping and various types of sensors to the refrigeration system.

The present invention discloses a refrigeration system comprising: a first stage heat exchanger having an inlet for receiving hot bleed air from the engine; a compressor having an inlet communicating with an outlet of the first stage heat exchanger; a heat exchanger having an inlet communicating with an outlet of the compressor; a first valve disposed between the hot edge outlet of the first stage heat exchanger and the hot edge inlet of the second stage heat exchanger and bypassing the compressor; a regenerator having a first inlet communicating with a hot edge outlet of the second stage heat exchanger; a condenser having a first inlet in communication with the first outlet of the regenerator and a second outlet communicating with the mixing chamber; the water separator , the inlet thereof is in communication with the first outlet of the condenser, the outlet thereof is connected to the second inlet of the regenerator; the turbine is connected to the second outlet of the regenerator, and the outlet is connected to the second inlet of the condenser; a two valve disposed between the outlet of the second stage heat exchanger and the mixing chamber, and bypassing the regenerator, the condenser, the water separator, and the turbine; the sensor for sensing parameters of the ambient air; the controller , its receiving parameters and with the reservation of the store In the flight state, when the parameter is not within the predetermined range, the first valve and the second valve are closed, and the hot bleed air is sequentially passed through the first stage heat exchanger, the compressor, and the second stage heat exchanger. In the regenerator, it is returned to the regenerator through the condenser and the water separator, and then enters the turbine and is then sent to the mixing chamber through the condenser; When the parameter is within the predetermined range, the first valve and the second port are opened, and the hot bleed air sequentially enters the mixing chamber through the first stage heat exchanger and the second stage heat exchanger.

Wherein the parameter includes a temperature value.

Further, the parameter further includes a humidity value.

Alternatively, the first valve is a one-way valve.

Preferably, the refrigeration system further includes a temperature control valve disposed between the hot edge outlet of the first stage heat exchanger and the outlet of the turbine.

Preferably, the first stage heat exchanger and the second stage heat exchanger exchange heat with external ram air flowing through the ram of the aircraft, and the refrigeration system further includes a ram air conditioning chamber for regulating the flow of the external ram air.

In the refrigeration system of the present invention, due to the increased economic mode, the operator can place the refrigeration system in an economic mode according to the prompt information of the controller under suitable conditions. When operating in low-temperature, low-humidity ambient air, the refrigeration system operating in economy mode eliminates the compression process and the water removal process to ensure that the refrigeration system is not using air cycle machines (fans, compressors, turbines) and The water separator is still capable of providing dry conditioned air while it is running. Therefore, in the state of flying at high altitude, there is still a large amount of ambient air as the chilled air entering the first and second stage heat exchangers as a cold source when the fan power is not consumed, and in addition, due to the high altitude flight The ambient temperature is low so that even if only the first and second stage heat exchangers are used to cool the hot bleed air, sufficient cooling is ensured. In this way, energy consumption can be effectively saved and its economic performance can be improved. DRAWINGS

In order to explain the present invention, an exemplary embodiment thereof will be described hereinafter with reference to the accompanying drawings, in which:

Figure 1 schematically shows a conventional refrigeration system;

Fig. 2 schematically shows a refrigeration system according to an embodiment of the present invention; Fig. 3 schematically shows a control principle diagram of a refrigeration system according to an embodiment of the present invention.

Similar features in different figures are indicated by like reference numerals. detailed description

Because the refrigeration system 200 of the present invention is optimized based on the conventional refrigeration system 100 described in the Background section, and in a preferred embodiment of the present invention, any components of the conventional refrigeration system are not eliminated. Therefore, the same or similar components will not be described again here. Specific improvements can be understood in conjunction with the following description.

A branch line 202 is installed between the outlet line of the second stage heat exchanger 106 and the line connected to the mixing chamber. The branch line 202 is provided with a valve 204, which is referred to as an economical valve in the present invention. When the economical valve 204 is open, airflow can pass from the outlet of the second stage heat exchanger 106 through the components of the regenerator 108, condenser 1 10, water separator 1 12 and turbine 114 into the mixing chamber.

A branch line 206 is installed between the outlet of the first stage heat exchanger 102 and the outlet of the compressor 104. The branch line 206 is provided with a one-way valve 208, which is referred to in the present invention. It is a one-way valve for the compressor. When the economical valve 204 is open, the air circulation machine (fan, compressor, turbine) almost stops the swirling airflow from passing through the compressor 104, at which point the airflow can pass through the compressor 104 from the compressor one-way valve 208.

Mounting another temperature sensor 210 and humidity sensor 212 in a non-pressurized zone (i.e., an area in communication with the outside atmospheric environment) can provide controller 120 with temperature and humidity information in the external environment. The controller 120 collects the signals from the temperature and humidity sensors 210, 212 and the flight altitude signals provided by the flight management system (FMS) and then makes a determination by comparing with preset values (including preset ranges). When the temperature, humidity, and height reflected by the above signals are all within a preset range, the controller 120 issues a prompt message that the economic mode can be activated. After the pilot receives the prompt message through the display or other equipment, the operation panel can be operated to make the refrigeration system 200 enter the economic mode. The economy valve 204 is opened after the economy mode is activated. At this time, only the ram air is used to effectively cool the hot bleed air to meet the cabin requirements.

More specifically, in a preferred embodiment of the present invention, the startup economy mode is ambient air that can be at a low temperature (eg, by the device sensing whether the ambient air is constant Low temperature range), low humidity ambient air (for example, whether the ambient air is a certain low humidity range through the device) and high altitude flight (for example, whether the aircraft is at a certain height range by means of the device) are jointly constrained. However, those skilled in the art will appreciate that it is not necessary for low humidity ambient air and high altitude flight constraints. This is because, when the aircraft is in high-altitude flight, the humidity of the hot bleed air of the engine can generally meet the requirements of the passenger cabin, so the humidity constraint can be omitted. In addition, the constraint condition of the high-altitude flight is mainly to make the controller 120 judge that the aircraft is not The standby, starting, etc. of the ground in an extremely cold area is in a high-altitude flight state, so that the ram air in the ram can be used to cool the first-stage and second-stage heat exchangers 102, 106 for extremely cold regions. For the aircraft, it is advantageous for the controller 120 to judge whether the aircraft is on the ground or at a high altitude. However, such judgment can also be obtained by capturing other parameters, such as data related to the cruise state, the operator. Instructions, etc. In other words, the aforementioned high-altitude flight constraints can be omitted and changed to constrain the aircraft to be in flight. However, it should be understood that this constraint is generally for higher temperature regions or seasons.

(such as southern China or summer) can be omitted. In this way, the parameters of the ambient air can be provided by the added temperature sensor 210 or the temperature sensor 210 and the humidity sensor 212. The state of the aircraft can be obtained indirectly from the data of the flying height. For example, if the flying height is 10,000 meters, it is known that the aircraft is generally located. In the cruise flight state, where the flight altitude data can be provided by the Flight Management System (FMS). Therefore, in the flight state, when the environmental parameter is low temperature or low temperature and low humidity, that is, when the ambient air temperature satisfies a preset numerical range or the temperature and humidity satisfy the preset numerical range, Enter the economic model. In the economic mode, the compression process and the water removal process can be eliminated to ensure that the refrigeration system 200 can still provide temperature suitable and dry when not using the air cycle machine (fan 119, compressor, turbine 114) and water separator 1 12 Adjust the air. In addition, in the economic mode, even if the fan 1 19 of one of the air cycle machine components is not in operation, a large amount of ambient air is supplied as ram air into the cold edges of the first and second stage heat exchangers 102, 106 as a cold source. Heat exchange is carried out. In addition, since the air temperature is generally high and the ambient temperature is low, only the first stage and the second stage heat exchange are used. The cooling of the hot bleed air by the devices 102, 106 ensures sufficient cooling.

2 is a schematic diagram of the refrigeration system 200, and FIG. 3 is a schematic diagram of the control system in the economic mode. Referring to Figures 2 and 3, wherein the flow path for hot bleed air to the mixing chamber and the flow path for ram air to the ram air outlet are shown in Figure 3, respectively. Once the economy mode is activated, the economic valve 204 is opened and the gas stream flows through the first stage heat exchanger 102, the compressor one-way valve 208 and the second stage heat exchanger 106, and bypasses the compressor 104, the turbine 114, The regenerator 108, the condenser 110 and the water separator 112 directly enter the mixing chamber supply cockpit. At this time, the amount of ram air passing through the cold side of the first stage heat exchanger 102 and the second stage heat exchanger 106 is controlled only by adjusting the opening degree of the ram air regulating valve 117 provided in the ram line to realize the hot bleed air. Effective cooling and meet the cabin temperature, humidity and pressure requirements. Here, since it is not necessary to increase the bleed air pressure, energy consumption can be effectively saved and the economic performance can be improved.

Specifically, the hot bleed air from the flow control valve 116 is first cooled by the first stage heat exchanger 102, then passed by the compressor one-way valve 208 through the compressor 104 and then into the second stage heat exchanger 106 and then cooled to The temperature required to meet the cabin requirements is finally passed through the economic valve 204 into the mixing chamber and supplied to the cabin. Wherein, the flow rate of the ram air is controlled by the opening degree of the ram air regulating valve 117 regulated by the controller 120.

The present invention is not limited in any way to the examples presented in the specification and the drawings, and many variations are possible within the scope of the invention as set forth in the claims.

Claims

Claim

1. A refrigeration system for an aircraft, comprising:

a first stage heat exchanger having an inlet for receiving hot bleed air from the engine;

a compressor having an inlet connected to an outlet of the first stage heat exchanger;

a second stage heat exchanger having an inlet connected to an outlet of the compressor;

a first valve disposed between the outlet of the first stage heat exchanger and the inlet of the second stage heat exchanger and bypassed by the compressor;

a regenerator having a first inlet connected to an outlet of the second stage heat exchanger;

a condenser having a first inlet communicating with the first outlet of the regenerator and a second outlet communicating with the mixing chamber;

a water separator having an inlet communicating with a first outlet of the condenser and an outlet communicating with a second inlet of the regenerator;

a turbine having an inlet in communication with a second outlet of the regenerator and an outlet connected to a second inlet of the condenser;

a second valve disposed between the outlet of the second stage heat exchanger and the mixing chamber, and bypassing the regenerator, the condenser, the water separator, and the turbine;

a sensor for sensing parameters of ambient air;

a controller that receives the parameter and compares it to a predetermined range of storage;

among them:

In the flight state, when the parameter is not within the predetermined range, the first valve and the second valve are closed, and the hot bleed air sequentially passes through the first stage heat exchanger, the compressor The second stage heat exchanger enters the regenerator, passes back to the regenerator through the condenser and the water separator, then enters the turbine and passes through the condenser Delivered into the mixing chamber;

When the parameter is within the predetermined range, the first valve and the second valve are opened, and the hot bleed air sequentially enters through the first stage heat exchanger and the second stage heat exchanger Into the mixing chamber.

s

2. The refrigeration system according to claim 1, wherein the parameter comprises a temperature value.

3. The refrigeration system of claim 2, wherein the parameter further comprises a humidity value.

4. The refrigeration system according to claim 1, wherein the first valve is a one-way valve.

5. The refrigeration system according to claim 1, wherein the refrigeration system further comprises a temperature control valve disposed between a hot side outlet of the first stage heat exchanger and an outlet of the turbine.

6. The refrigeration system according to claim 1, wherein the first stage heat exchanger and the second stage heat exchanger exchange heat with external ram air flowing through a ram of an aircraft, the refrigeration system A ram air regulating valve for regulating the flow of the external ram air is also included.