JPH0325096A - Cooling device utilizing airframe outer surface cooler for aviation electronic equipment - Google Patents

Abstract

PURPOSE:To improve cooling capacity by installing a heat exchanger in the airframe inner position of an aircraft, in such a way as to be in contact with the outer surface wall member of the airframe, and circulating refrigerant stored/loaded in the airframe through the heat exchanger. CONSTITUTION:Refrigerant in a reservoir 1 is circulated by a pump 2 through a heat exchanger 3 installed at the airframe outer surface inside the airframe of an aircraft. During a flight, air, a heat exchanging medium, acts as force refrigerant, thus improving cooling capacity.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to the outer surface (
This invention relates to a cooling system for avionics equipment that uses a heat exchanger (cooler) installed inside a member (outer surface) of a structure such as a fuselage, wing, nose, bod, or strut in contact with the outer surface.

The present invention is particularly effective in dealing with a new heat load when it occurs in an existing aircraft.

[Conventional technology]

Conventionally, the following types of cooling systems for aircraft are known.

Conventional freshwater cooling systems generally store low-temperature refrigerant in a gaseous tank in advance, and pump the stored refrigerant to the heat generating part of the electronic device to circulate the refrigerant.

Conventional cooling equipment with a refrigerator uses a refrigeration cycle, in which the refrigerant is pressurized by a compressor to produce high-pressure steam, and then
A common cycle is to circulate high-pressure liquid, low-pressure liquid, and low-pressure vapor to remove heat from electronic devices using an evaporator.

[Problem to be solved by the invention]

In a stored water cooling system, one refrigerant circulation system cannot obtain low temperature from other systems. Therefore, the temperature of the refrigerant in the gaseous reservoir (tank) increases monotonically as the cooling device is used due to the heat generated by the electronic device, and eventually reaches the operating limit temperature of the electronic device.

That is, in this system, the cooling capacity of the electronic device is determined by the refrigerant capacity of the reservoir, and the cooling time is guaranteed only by the refrigerant capacity of the reservoir.

In addition, in a cooling device with a refrigerator, if the drawbacks of the reservoir type cooling device are overcome and the refrigeration cycle is designed in consideration of the amount of heat generated by the electronic equipment, the cooling duration becomes infinite. However, installing a refrigerator poses problems such as a) power consumption due to the use of the refrigerator and b) weight and space of the cooling device due to the use of the refrigerator. In particular, the aSb problem described above becomes a big problem when dealing with a newly generated heat load.

Furthermore, when air is used as a low temperature source in a gaseous environment control system that includes cooling of electronic equipment, it has conventionally been common to provide an air intake port in the fuselage of an aircraft to take in ram air for heat exchange.

However, if a new heat load is generated and an attempt is made to similarly use ram air for cooling, it is necessary to provide a new air intake port in the fuselage for this new ram air. Providing such air intakes may impair the aerodynamic flight performance of the aircraft.

[Means to solve the problem]

The present invention relates to a cooling device for avionics equipment, in which a heat exchanger is installed in a position inside the gas of an aircraft in contact with an outer surface wall member of the aircraft body, and a refrigerant stored and carried in the gas is transferred to the cooling device for avionics. The above-mentioned problem is solved by a cooling device using an airframe outer surface cooler for avionics equipment, which is characterized by improved cooling capacity by circulating heat through the heat exchanger.

[For production]

The present invention circulates a refrigerant through a heat exchanger (cooler) installed on the outer surface of the aircraft in a gaseous state, and uses air, which is a heat exchange medium, for forced cooling during flight.

As a result, when the present invention is applied to a reservoir type cooling device, air, which is a heat exchange medium, acts as a forced cooling medium during flight, and the cooling capacity is improved.

In addition, in a cooling device with a refrigerator, a state in which the refrigerator is not used is realized, resulting in a significant reduction in power consumption and weight of the entire cooling system.

Moreover, even when the present invention is applied to an existing aircraft, there is no need to newly provide an air intake port, and aerodynamic flight performance is not impaired in any way.

〔Example〕

(a) Embodiments of the reservoir water type cooling device (1) Basic circuit and control diagram of the cooling device Figures 1 and 2 are basic circuit diagrams of the reservoir water type cooling device according to the present invention ((a) in each figure). Figure) and control diagrams (Figure (b) of each figure) are shown schematically.

In the case of stored water cooling devices, there are two types depending on the type of tank (reservoir). FIG. 1 shows an embodiment of an oven type reservoir, and FIG. 2 shows an embodiment of an accumulator type reservoir.

In FIGS. 1 and 2, a low-temperature refrigerant is stored in a reservoir (R) 1. A bomb 2 driven by a power source (EPS) sucks refrigerant from a reservoir 1 to cool the heat load (EHL) of the electronic device.

A pressure regulating valve (R V) connected to the reservoir 1 regulates the pressure within the reservoir 1. The flow regulating valve (FV) regulates the flow rate of the refrigerant flowing from the bomb 2 to the heat load (EHL) of the electronic equipment.

In addition, as shown in FIG. 1(a) and FIG. 2(a),
A flow rate sensor (LS), a pressure sensor (PS), a temperature sensor (TS), and a flow rate sensor (FS) are provided to detect the characteristics of the refrigerant in each part.

A three-way switching solenoid valve (S V) is installed between the heat load (E H L) of the electronic equipment and the reservoir (R) 1 (Fig. 1) or between the heat load (L) and the outlet of the reservoir (R) 1. 4 is provided. By switching the three-way solenoid valve 4, the refrigerant that has left the heat load (E H L) of the electronic equipment reaches the three-way solenoid valve 4 as it is, or is placed in contact with the outer wall member of the fuselage according to the present invention. The heat exchanger 3 then reaches the three-way switching solenoid valve 4.

(2) The refrigerant in the working reservoir 1 is sucked up by the bomb 2 and sent to the cooling section (EHL) of the electronic equipment. In the normal mode, the refrigerant that has passed through the cooling section (EHL) of the electronic device returns to the reservoir 1 through a route different from that of the heat exchanger 3 installed in contact with the outer surface wall member of the aircraft body.

However, when the following relationships occur, the electronic control unit (EC)
A three-way switching solenoid valve (SV) receives a signal from the heat exchanger 3 and switches the heat exchanger 3 to a circuit through which the refrigerant passes.

That is, the conditions for controlling the refrigerant to pass through the heat exchanger 3 are to satisfy the following equations 1 to 3 at the same time.

TB,In (or T2,out)>T.
(Formula 1) where TI! ．． In is the heat negative of electronic equipment n:
This is the inlet temperature of part J (ie, the cooling device outlet temperature), and is detected by the temperature sensor TSI.

Also, T. , OLIt is the outlet temperature of the heat load part of the electronic equipment (
In other words, the temperature sensor TS
I is moved to the exit location of the heat load section and installed for detection.

Therefore, in this case, the Tp,InDI Sadakawa sensor is not required.

Furthermore, Tw is the aircraft outer surface temperature (detected by temperature sensor TS2) TE, in>TLow (Formula 2)
Here, "rt.ow" is the minimum operating temperature of electronic equipment,
Set in the controller.

T=, In<T. (Equation 3) Here, T1 is the maximum operating temperature of the electronic device, and is set in the controller.

(b) Embodiment of cooling device with refrigerator (1) Application circuit and control diagram of cooling device Figures 3 and 4 show circuits that have been further applied and developed from the basic circuit shown in Figures 1 and 2. .

That is, FIG. 3(a) shows a refrigerant circulation circuit diagram of a cooling system having an oven type reservoir, and FIG. 3(b) shows a control circuit diagram of the controller. Also, Figure 4 (
4(a) shows a refrigerant circulation circuit diagram of a cooling system having an accumulator reservoir, and FIG. 4(b) shows a control circuit diagram of the controller.

The paper cycle shown in FIGS. 3 and 4 is a cycle having normal refrigeration functions, including a compressor 11 that compresses gaseous refrigerant, a condenser 12 that cools and heats refrigerant vapor to condense and liquefy it, and a It is composed of an expansion valve 13 that expands the refrigerant, an evaporator 14 that evaporates the refrigerant to remove surrounding heat, and a liquid receiver.

In addition to the above-mentioned known Baber cycle circuit, as shown in Figs. A three-way solenoid valve (SV) 4) is provided.

(2) Operation The basic structure and operation except for the heat exchanger 'a3' are the same as the conventional device. However, T2,In>Tw (Formula 4) (
Here, TH,in is the temperature detected by the sensor TSl, and Tw is the temperature detected by the sensor TS2), the three-way switching solenoid valve (SVl4 is switched,
The flow path of the refrigerant is switched to the passage circuit of the heat exchanger 3 disposed in contact with the outer surface member.

However, under conditions where the capacity of the heat exchanger 3 placed in contact with the outer surface member cannot offset the heat load of the electronic device EHL, the maximum operating temperature of the electronic device is TUP, and Tg. In-Tup (Formula 5)
Then, the three-way switching solenoid valve (SV) 4 is switched to the circuit passing through the evaporator 14, and the paper cycle mode is set.

Next, the installation location of the body outer surface member contact heat exchanger 3 will be described.

The fuselage outer surface heat exchanger may be installed at any position on the fuselage skin inside the aircraft. In other words, the target is the gas inside of the outer surface members of structures such as the fuselage, wings, aircraft, bod, and struts.

However, as common sense suggests, it is preferable to avoid positions that are a long distance backward from the stagnation point where the temperature boundary layer becomes thick, as it is expected that the heat exchange efficiency will be poor.

FIG. 5 briefly shows an example of the heat exchanger 3 incorporated into the outer surface member.

A box-shaped header 32 is fitted inside the outer surface member 31, and the header 32 is provided with an artificial conduit 33 and an outlet conduit 34. Inside the header 32, as shown in FIG. 6, an end plate 36 is supported by a cover plate 34 and a partition plate 35, parallel to the outer surface portion 31 and with a gap therebetween. A lanced offset fin 37 shown in the figure is provided. Such a lanced offset fin 37 has the advantage that the flow is not blocked in the heat exchanger and it easily follows the 14II rate of the outer surface, so that it is suitable as a heat exchange skewer.

In the heat exchanger 3 of this embodiment, there are two buses in which the flow is reversed once from the inlet pipe line 33 to the outlet pipe line 342, and one layer of fins is shown. pump performance,
Taking pressure drop, heat exchange rate, etc. into consideration, it is also possible to use a heat exchanger with three or more buses and a multilayered fin structure.

An example of a method for attaching the heat exchanger 3 described above is shown in FIGS. 8 and 9. A hole 41a is made in an outer surface member 41 such as the fuselage of an aircraft to match the outer surface member 31 of the heat exchanger 3 (FIG. 8), and the heat exchanger 3 is installed in this hole 41a. 41 are joined by seam welding. The thickness of the outer surface member 31 of the heat exchanger 3 is approximately the same as the thickness of the outer surface member 41 of the aircraft.

In addition, instead of the seam welding described above, a doubler is drilled around the fitting frame, as is commonly done by aircraft manufacturers.
Riveting may be done from the outside.

〔Effect of the invention〕

The present invention provides the following effects.

(1) When the present invention is applied to a storage water type cooling system and a cooling system with a cooling machine, depending on the flight conditions (altitude, Mach number), cooling can be continued for an infinite amount of time. Reservoirs, pumps, and external heat exchangers can be sized to suit cooling requirements.

More specifically, FIGS. 10 and 11 show examples of calculations of the refrigerant temperature in the reservoir with respect to the cooling duration when the outer surface temperature is constant at 20° C. and 30° C., respectively. The conditions for subtraction are: Reservoir capacity: 61j Refrigerant used: Nybline Z-1 80% heat load: 3
．． 7KW Refrigerant flow rate 71/gin Tup"50°C, T,,ows*5°C, Cooler outer surface area 5.07rt2 In addition, Fig. 12 shows an example of trial calculation of the outer surface temperature for an aircraft's Mach 8 number on a high temperature day.

Since the cooling temperature of electronic devices is usually about 0 to 50 degrees Celsius,
It can be seen from FIGS. 10 and 11 that cooling is possible for 60 minutes or more, and from FIG. 11 that it is possible to cool down to a Mach number of about 1.5.

(2) Furthermore, in the stored water cooling system and the refrigerator-equipped cooling system according to the present invention, the low-temperature source used for cooling is forced cooling air outside the aircraft, and the energy source is unlimited during flight.

In particular, in the cooling device with a refrigerator of the present invention, it is possible to realize a state in which the refrigerator is not used during the flight. Therefore, power consumption can be significantly reduced. Therefore, the amount of melon in the entire cooling system can be reduced.

(3) In conventional water cooling systems, a method is adopted in which low-temperature refrigerant is sent from ground support equipment to a reservoir immediately before flight, but according to the present invention, the refrigerant in the reservoir can be brought to a low temperature during flight. Can be done. Therefore, conventional ground support equipment can be made unnecessary.

In addition, in the reservoir water type cooling device and the refrigerator (1) cooling device of the present invention, it is possible to save the trouble of sending low-temperature refrigerant to the reservoir in advance and storing it ffi' before the start of the flight.

(4) Furthermore, the reservoir water type cooling device and the refrigerator-equipped cooling device of the present invention are not provided with an air intake port.

Therefore, unlike a general gaseous environment control system that provides an air intake, takes in ram air, and secures a low temperature source, the present invention does not impair aerodynamic flight performance in any way.

[Brief Description of the Drawings] Figures 1 (a) and (b) are a circuit diagram and control diagram of an embodiment of a reservoir type cooling device with an oven type reservoir according to the present invention, and Figure 2 (a) 3(b) is a basic circuit diagram and control diagram of an embodiment of the accumulated water type cooling device according to the present invention with an accumulator type reservoir {=i, and FIG. 3(a) is a refrigerant circulation circuit of a cooling system having an oven type reservoir. 3(b) is a control circuit diagram of the controller, FIG. 4(a) is a main part of the refrigerant circulation circuit diagram of the cooling system for heating the accumulator reservoir, and FIG. 4(b) is the control circuit diagram of the controller. 5 is an oblique view of the heat exchanger according to the present invention, FIG. 6 is an oblique view of the heat exchanger of the present invention with the header removed, and FIGS. 7 to 9 are oblique views of the heat exchanger of the present invention. Figures 10 and 11 are oblique diagrams showing the installation state, and diagrams showing the results of different calculations of the refrigerant temperature in the reservoir with respect to the cooling duration when the outer surface temperature is constant at 20°C and 30°C, respectively. , FIG. 12 is a diagram showing the results of a trial calculation of the outer surface temperature with respect to the Mach number of an aircraft with a high temperature of 1. 1... Reservoir, 2... Bomb, 3... Heat exchanger, 4... Three-way 12J exchange solenoid valve. Fig. 6 Fig. 7 Fig. 10 Fig. 11 Fig. Offshore carp f time (intermediate) Fig. 9 Fig. 12 Fig. , Ha Atsushi

Claims (1)

[Claims] 1. In a cooling system for avionics equipment, a heat exchanger is installed inside the aircraft fuselage in contact with the outer surface wall member of the aircraft, and a refrigerant stored and carried in a gas is circulated through the heat exchanger to increase the cooling capacity. A cooling system that utilizes an airframe external surface cooler for avionics equipment, which is characterized by improved performance.