U.S. patent application number 12/020169 was filed with the patent office on 2008-09-04 for device for cooling electrical equipment in a turbomachine.
This patent application is currently assigned to HISPANO - SUIZA. Invention is credited to Eric DE WERGIFOSSE, Huguette Fichefet.
Application Number | 20080209914 12/020169 |
Document ID | / |
Family ID | 38476140 |
Filed Date | 2008-09-04 |
United States Patent
Application |
20080209914 |
Kind Code |
A1 |
DE WERGIFOSSE; Eric ; et
al. |
September 4, 2008 |
DEVICE FOR COOLING ELECTRICAL EQUIPMENT IN A TURBOMACHINE
Abstract
A device for cooling electrical or electronic equipment in a
turbomachine, such as a unit for controlling actuators for
variable-geometry elements, the device comprising at least one
vortex tube having an inlet connected to means for feeding
pressurized air taken from an element of the turbomachine, and a
cold air outlet connected to means for cooling the electrical
equipment.
Inventors: |
DE WERGIFOSSE; Eric; (Saint
Augustin, FR) ; Fichefet; Huguette; (Saint Augustin,
FR) |
Correspondence
Address: |
OBLON, SPIVAK, MCCLELLAND MAIER & NEUSTADT, P.C.
1940 DUKE STREET
ALEXANDRIA
VA
22314
US
|
Assignee: |
HISPANO - SUIZA
COLOMBES
FR
|
Family ID: |
38476140 |
Appl. No.: |
12/020169 |
Filed: |
January 25, 2008 |
Current U.S.
Class: |
62/5 |
Current CPC
Class: |
F25B 9/04 20130101; H01L
2924/0002 20130101; H01L 2924/0002 20130101; H01L 2924/00
20130101 |
Class at
Publication: |
62/5 |
International
Class: |
F25B 9/04 20060101
F25B009/04 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 30, 2007 |
FR |
07/00643 |
Claims
1. A device for cooling electrical equipment in a turbomachine, the
device comprising at least one vortex tube having an inlet
connected to pressurized air feed means, and a cold air outlet
connected to means for cooling the electrical equipment, wherein
the vortex tube is fed with pressurized air via a heat exchanger
having a secondary circuit fed with cooling fluid by the outlet of
the means for cooling the electrical equipment or by the hot air
outlet of the vortex tube.
2. A device according to claim 1, wherein the pressurized air feed
means comprise means for taking air from an annular duct for
passing a flow of cool air or a secondary flow of the
turbomachine.
3. A device according to claim 1, wherein the pressurized air feed
means comprise means for taking air from a compressor of the
turbomachine.
4. A device according to claim 1, wherein the pressurized air feed
means comprise an auxiliary compressor driven by an accessory
gearbox of the turbomachine.
5. A device according to claim 1, wherein the heat exchanger
includes two secondary circuits fed with cooling air, one by the
outlet from the means for cooling the electrical equipment, and the
other by the hot air outlet from the vortex tube.
6. A device according to claim 1, wherein the vortex tube is fed
with air at a pressure of a few bars.
7. A device according to claim 1, wherein the temperature of the
cold air leaving the vortex tube is about 50.degree. C. lower than
the temperature of the pressurized air.
8. A device according to claim 1, wherein the vortex tube is of the
double-circuit type and includes a second inlet connected to the
pressurized air feed means.
9. A device according to claim 1, including a plurality of vortex
tubes associated in series or in parallel.
10. A turbomachine, including a device according to claim 1 for
cooling electrical equipment.
Description
[0001] The present invention relates to a device for cooling
electrical or electronic equipment in a turbomachine.
BACKGROUND OF THE INVENTION
[0002] A turbomachine includes a certain number of pieces of
electrical or electronic equipment, such as units for controlling
actuators of variable-geometry elements, which pieces of equipment
generate a large amount of heat that needs to be removed in order
to maintain acceptable temperatures for the electrical equipment
and also for certain elements of the turbomachine situated in the
vicinity of said equipment.
[0003] Known cooling devices generally comprise means for
circulating a cooling fluid such as oil, fuel, or air, and they are
often bulky and complex to implement. Furthermore, those devices
present risks of leakage, and they require regular maintenance
operations, which are lengthy and expensive.
OBJECTS AND SUMMARY OF THE INVENTION
[0004] A particular object of the invention is to provide a
solution to those problems that is effective and inexpensive.
[0005] For this purpose, the invention provides a device for
cooling electrical equipment in a turbomachine, the device
comprising at least one vortex tube having an inlet connected to
pressurized air feed means, and a cold air outlet connected to
means for cooling the electrical equipment, wherein the vortex tube
is fed with pressurized air via a heat exchanger having a secondary
circuit fed with cooling fluid by the outlet of the means for
cooling the electrical equipment or by the hot air outlet of the
vortex tube.
[0006] In known manner, a vortex tube, also known as a Ranque tube,
serves to uses the vortex effect to create a flow of cold air and a
flow of hot air derived from a flow of compressed air at an
intermediate temperature. The inlet air is injected tangentially
into a chamber connected to the tube so as to create a rapidly
swirling flow that is directed towards one end of the tube, which
end is fitted with a conical outlet valve. A portion of the air
leaves the tube via said valve, while another portion of the air is
reflected on said valve and then progresses along the tube in the
opposite direction with swirling motion inside the injected air,
while yielding heat to said air, and then leaving via the opposite
end of the tube.
[0007] The cooling device of the invention has one or more vortex
tubes that are fed with pressurized air taken by suitable means
from a compressor of the turbomachine or from an annular duct for
passing a secondary air flow such as the fan duct of the
turbomachine. The cold air outlet from each vortex tube is
connected to a heat exchanger associated with the equipment for
cooling, or to a system for injecting air into the electrical
equipment for cooling.
[0008] Vortex tubes are simple to make and to implement and they
enable cold air to be produced with resources that are locally
available. They are fed with air at a pressure of several bars
(typically lying in the range 5 bar to 10 bar) and they generate
cold air at a temperature that may be about 50.degree. C. lower
than the temperature of the inlet air. Furthermore, vortex tubes
are inexpensive, reliable, and have a lifetime that is relatively
long without requiring special maintenance, since they do not
include any moving parts.
[0009] The cooling device may include a heat exchanger having a
primary circuit with an inlet connected to the outlet of the means
for taking air and an outlet connected to the inlet of the vortex
tube, and including at least one secondary circuit that is fed with
cooling fluid.
[0010] At least some of the air that has been used for cooling the
electrical equipment can be injected into a secondary circuit of
the heat exchanger in order to assist in cooling the air taken from
the turbomachine. Similarly, the air coming from the hot outlet of
the vortex tube can be injected into a secondary circuit of the
heat exchanger for assisting in cooling the air taken in, providing
its temperature is lower than that of the air taken from the
turbomachine. The heat exchanger may thus have two secondary
circuits fed with cooling air, one by the outlet from the means for
cooling the electrical equipment, the other by the hot air outlet
from the vortex tube.
[0011] The vortex tube may be of the double-circuit type, in which
case it includes a second inlet tube connected to the pressurized
air feed means, with this disposition making it possible to double
efficiency.
[0012] It is also possible to use a plurality of vortex tubes
associated in series or in parallel for cooling the electrical or
electronic equipment.
[0013] The invention also provides a turbomachine, including an
electrical or electronic equipment cooling device as described
above.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] The invention can be better understood and other details,
characteristics, and advantages of the present invention appear on
reading the following description made by way of non-limiting
example and with reference to the accompanying drawings, in
which:
[0015] FIG. 1 is a highly diagrammatic representation of a device
of the invention for cooling electrical equipment of a
turbomachine;
[0016] FIG. 2 is a diagrammatic axial section view of a vortex tube
of the cooling device of the invention; and
[0017] FIG. 3 is a section view on line III-III of FIG. 2.
MORE DETAILED DESCRIPTION
[0018] FIG. 1 is a highly diagrammatic representation of the device
of the invention for cooling electrical or electronic equipment 12
in a turbomachine 10, the device comprising a vortex tube 14 or
Ranque tube fed with pressurized air that is taken from an element
16 of the turbomachine, said element 16 being constituted for
example by a fan duct, a low pressure or high pressure compressor,
or an auxiliary compressor of smaller size driven by an accessory
gearbox of the turbomachine.
[0019] The vortex tube 14 has an inlet 18 opening out into a
chamber 20 formed between the ends of the tube, the tube having a
hot air outlet 22 at one of its ends and a cold air outlet 24 at
its other end. The well-known operation of the vortex tube is
described in detail below with reference to FIGS. 2 and 3.
[0020] In the example shown, the cooling device further comprises a
heat exchanger 30 having one or more stages comprising a primary
circuit with an inlet 32 connected to means for taking air from the
element 16 of the turbomachine, and an outlet 36 connected by a
duct 38 to the inlet 18 of the vortex tube 14.
[0021] The air that is taken is cooled in the heat exchanger 30 by
natural convection (and also by radiation), and/or by heat exchange
with a cooling fluid flowing in a secondary circuit 31 of the heat
exchanger 30.
[0022] The heat exchanger 30 may optionally include another
secondary circuit for cooling fluid, with an inlet 40 connected by
a duct 42 to the outlet of a heat exchanger 50 used for cooling the
electrical equipment, the air rejected from the outlet 44 of the
secondary circuit of the heat exchanger 30 possibly being used for
cooling elements of the turbomachine.
[0023] Similarly, the hot air outlet 22 from the vortex tube 14 can
be connected by a duct 46 to an inlet 34 of another secondary
circuit of the heat exchanger 30.
[0024] The cold air outlet 24 from the vortex tube is connected
either to the heat exchanger 50 or to an air ejector system
associated with the electrical equipment 12, this electrical
element being constituted, for example, by an electronic unit for
controlling variable-geometry portions of the turbomachine.
[0025] The device may also include pressurized air filter means
mounted at 32 or at 38 for limiting wear in the vortex tube and
thus increasing its lifetime.
[0026] The cooling device of the invention operates as follows:
pressurized air is taken from the element 16 and passes through the
primary circuit of the heat exchanger 30 so as to be cooled by
exchanging heat with a cooling fluid flowing in the secondary
circuit 31 and possibly also with air flowing in the secondary
circuit 40-44 of the heat exchanger 30, and with hot air delivered
by the outlet 22 from the vortex tube. The cooled air leaving the
heat exchanger 30 is injected tangentially into the chamber 20 of
the tube that is situated in the vicinity of the first end 24 of
the tube (FIG. 2). This chamber 20 is generally cylindrical in
shape so as to cause the injected air to move and so as to create a
rapid swirling flow 52 inside the tube, this flow going towards the
second end 22 of the tube (arrow 54). The air at the outer
periphery of the swirling flow is relatively hotter while the air
situated at the inner periphery of the swirling flow is relatively
cooler.
[0027] A frustoconical control valve 56 is mounted in the second
end 22 of the tube and co-operates with the inside surface of the
tube to define an annular air outlet channel for the air situated
at the outer periphery of the swirling flow, i.e. for the hot air
(arrows 58). The central portion of the swirling flow is reflected
on the valve 56 and forms a second swirling flow 60 that flows in
the opposite direction inside the first swirling flow 52 (arrow
62), while yielding heat thereto, until it reaches the first end 24
of the tube (arrow 64).
[0028] The vortex tube may be of the double-circuit type in which
case it has a second air inlet at its end 22 opposite from the
chamber 20 for the purpose of improving the efficiency of the tube,
as is well known in the art. In the example shown, an orifice 66 on
the axis of the tube is formed through the control valve 56 and can
be connected to air feed means (arrow 68), this air, for example,
having the same temperature and a lower pressure than the air
injected into the chamber 20.
[0029] In a particular embodiment of the invention, the flow rate
of air taken from the element 16 and passing through the heat
exchanger 30 is 2833 liters per minute (L/min), this air being at a
pressure of 6.3 bar and at a temperature of 200.degree. C. The
cooling fluid fed to the secondary circuit 31 of the heat exchanger
30 is air at a temperature of 90.degree. C. and it enables the
temperature of the pressurized air fed to the vortex tube 14 to be
reduced to 100.degree. C. The heat exchanger 50 is fed with cold
air at a flow rate of 1840 L/min, this air having a temperature of
57.degree. C. at the inlet to the heat exchanger 50 and a
temperature of about 80.degree. C.-90.degree. C. at the outlet from
the heat exchanger, which air can subsequently be injected into a
secondary circuit of the heat exchanger via the duct 42.
[0030] A plurality of vortex tubes 14 may be connected in series or
in parallel for the purpose of cooling one or more pieces of
electrical or electronic equipment. The dimensioning of the or each
vortex tube depends on the flow rate and the temperature of the
cold air at the outlet from the tube, which flow rate and
temperature are determined as a function of the type of equipment
to be cooled.
* * * * *