[0001] The present invention relates to a device for making artificial snow.
[0002] A device for making artificial snow according to the preamble of claim 1 is known
from
FR1372024.
[0003] Devices are already known for manufacturing artificial snow by using water and compressed
air, whereby water is atomised in compressed gas and.the atomised water is frozen
by the cooling effect of the air expansion.
[0004] A compressor is used to supply the compressed gas in the known devices.
[0005] It is known that the compressed gas, which generally consists of air, can have a
very high temperature at the outlet of this compressor and can also be moist.
[0006] The known devices thus also contain one or more after-coolers to cool the compressed
air, such that the moisture in the compressed air condenses as a result of cooling
and can be separated as a condensate using a water separator or similar.
[0007] These after-coolers are generally constructed in the form of air-air regenerative
heat exchangers, in which the incoming hot compressed air is cooled by compressed
air that has already been cooled.
[0008] The known devices are incorporated in a building of substantial dimensions in which
the compressor is housed, and whereby the inlet of the compressor is connected to
the outside air to draw in the air to be compressed, while the outlet of the compressor
installation is connected to a snow gun to supply the compressed air.
[0009] The pipes provided for the realisation of the abovementioned connections are sizeable
in order to emit the heat from the compressed air to the space in the abovementioned
building, and to utilise this heat to warm up the cold air drawn in.
[0010] A disadvantage is that this installation is quite large and rather immobile.
[0011] Another disadvantage is that the temperature of the compressed gas at the inlet of
the snow cannon is difficult to control.
[0012] A disadvantage attached to this is that the quality of the snow produced depends
on the weather conditions, such that the device has rather limited reliability.
[0013] Improved devices are also known, in which there is an additional heat exchanger after
the after-cooler for the purpose of controlling the temperature of the outgoing compressed
gas.
[0014] A disadvantage is that such a device only enables rudimentary control of the temperature,
such that it is not possible to produce high-quality snow under all conditions.
[0015] A further disadvantage is that the heat exchanger cannot prevent moisture condensing
in the after-cooler and freezing there.
[0016] A further additional disadvantage is that the known devices use a lot of energy.
[0017] The purpose of the present invention is to provide a solution to one or more of the
abovementioned and/or other disadvantages, by providing a device for making artificial
snow by means of a snow cannon in which water is atomised by means of compressed air,
whereby this device is provided with a compressor for supplying compressed air, which
compressor is positioned in a compressor area with an inlet for supplying air from
the environment and an outlet to deliver the compressed air to the snow cannon via
a pipe, whereby, according to the specific characteristic of the invention, the abovementioned
device comprises a heat exchanger with a primary part and a secondary part, whereby
the compressed air from the compressor is guided through the primary part, and whereby
the abovementioned secondary part makes part of the evaporator of a closed cooling
circuit in which a coolant is circulated by means of a compressor element that is
driven by a drive, and whereby the abovementioned device includes a controller for
controlling the abovementioned cooling circuit in order to obtain the desired temperature
or pressure dew point at the outlet of the primary part of the heat exchanger.
[0018] An advantage is that the temperature of the compressed air at the outlet of the primary
part of the heat exchanger can be well controlled, such that the snow produced is
always of a very good quality and the quality of the snow is not subject to the weather
conditions.
[0019] The invention enables the cooling circuit to be controlled accurately so that the
desired temperature and/or desired pressure dew point of the compressed air is realised.
[0020] Another advantage is that the device is relatively compact with respect to the known
devices.
[0021] An advantage attached to this is that the device is cheaper, not only with regard
to the installation cost but also with regard to energy consumption.
[0022] In the most practical embodiment the device can be incorporated into a container,
and thus be produced as a mobile device.
[0023] An advantage of this is that the container can be easily transported, such that the
device can deliver compressed air for the production of snow at different locations,
and consequently a relatively large piping system is not needed to connect different
snow cannons to one centrally located device for supplying compressed air.
[0024] In a practical embodiment of the invention, the cooling circuit contains a second
heat exchanger that forms the condenser of the cooling circuit, and which is located
downstream from the compressor element and upstream from the expansion means provided
in the cooling circuit.
[0025] In the most practical embodiment the coolant that flows through this second heat
exchanger is cooled by a fan. Preferably the abovementioned fan is arranged such that
it blows air over the second heat exchanger to the .compressor area.
[0026] An advantage of this is that the fan distributes warm air in the compressor area,
such that the temperature in the compressor area is above 0° thereby avoiding freezing,
and damage due to freezing is thus completely ruled out.
[0027] A further advantage is that no extra large pipes are needed between the outlet of
the primary part of the heat exchanger and the inlet of the snow cannon.
[0028] Preferably the temperature of the compressed air at the outlet of the primary part
of the heat exchanger is less than 8° Celsius and preferably around 3° Celsius.
[0029] An advantage is that good-quality snowflakes can be produced in this temperature
range and the total production time for making the snow is reduced.
[0030] Preferably the compressed air at the outlet of the primary part of the heat exchanger
presents a pressure of 8 bar or almost 8 bar.
[0031] Preferably the air is compressed by means of an oil-free compressor such as a water-injected
screw compressor.
[0032] An advantage is that the compressed air cannot be contaminated by oil particles,
such that this compressed air does not necessarily have to go through one or more
filters, which of course has a favourable effect on the cost and size of the device.
[0033] With a water-injected compressor the risk of contaminating the air itself is even
completely ruled out.
[0034] With the intention of better showing the characteristics of the invention, a preferred
embodiment is described hereinafter by way of an example, without any limiting nature,
of a device according to the invention, with reference to the accompanying drawing,
which shows a device according to the invention for making artificial snow.
[0035] The device 1 for making artificial snow primarily contains a compressor area 2 with
a housing 3, which has an inlet 4 for supplying air from the environment and an outlet
5 for removing the compressed gas such as air.
[0036] In a practical embodiment of the invention, the housing 3 is formed by a container
that can be mobile or by a building or similar.
[0037] The dimensions of the housing 3 can, for example, be limited to a floor plan of six
metres by six metres, in contrast to existing devices where buildings are used with
dimensions that are dozens of metres long and wide.
[0038] There is a grid in a wall of the housing 3 that forms the inlet 4 through which the
surrounding air is drawn according to the direction of the arrow L.
[0039] In the housing 3 there is the abovementioned outlet 5 whereby a snow cannon 6 can
be supplied with compressed air through a pipe 7.
[0040] The snow cannon 6 also has a supply pipe 8 for water, such that water is atomised
by the compressed air in a known way at the outlet of the snow cannon 6, such that
snow crystals are formed that disperse from the muzzle of the snow cannon 6.
[0041] For the production of the compressed air, there is a compressor 9 in the compressor
area 2 with an inlet for drawing in air and an outlet 11 for removing the compressed
air.
[0042] The abovementioned compressor 9 is driven in a known way by means of a drive 10,
such as for example, but not necessarily, an electric motor.
[0043] The abovementioned compressor 9 can consist of a single compressor element, as shown
in the drawing, but can also be constructed as a multistage compressor, whereby the
air is compressed by a number of consecutive compressor elements.
[0044] In a particular embodiment the compressor 9 only contains water-injected compressor
elements and intercoolers can also be placed between successive pressure stages. It
goes without saying that the invention is not limited to this, as a different type
of oil-free compressor, or an oil-injected compressor with appropriate air filtering
can be used just as well.
[0045] In a preferred embodiment of the invention, the compressor 9 is set to a maximum
service pressure of between 8 bar and 9 bar, and preferably a maximum service pressure
of 8.5 bar or almost 8.5 bar.
[0046] According to the invention, there is a heat exchanger 12 in the compressor area 2
for the cooling of the compressed air, with a primary part and a secondary part, whereby
the inlet 13 of the primary part is connected to the outlet 11 of the compressor 9.
[0047] Preferably the heat exchanger 12 is designed such that the pressure drop of the compressed
air that goes through the primary part is less than 0.2 bar, or even better less than
0.1 bar, and preferably even less than 0.05 bar.
[0048] It is known that by reducing the temperature, the moisture in the compressed air
will condense.
[0049] At the outlet 14 of the primary part of the heat exchanger 12 there is preferably
a liquid separator 15 that can remove the condensed water.
[0050] According to the invention, the secondary part of the abovementioned heat exchanger
12 forms the evaporator 16 of a closed cooling circuit 17 that is filled with a coolant
or cooling fluid.
[0051] As is known, the coolant is circulated by means of a compressor element 18 in the
cooling circuit 17, and this compressor element 18 is driven by a drive 19.
[0052] Furthermore, in the closed cooling circuit 17 between the outlet of the compressor
element 18 and the secondary part of the heat exchanger 12, there is successively
a condenser 20 and expansion means, for example in the form of an expansion valve
21.
[0053] In a practical embodiment the abovementioned condenser 20 is formed by a second heat
exchanger and this second heat exchanger is cooled by means of a fan 22 that blows
air over the condenser 20 and this air is further blown into the compressor area 2.
[0054] In the most practical embodiment of the invention the speed of the abovementioned
fan 22 can be adjusted in order to control the temperature of the coolant at the outlet
of the condenser 20. To this end the abovementioned fan can, for example, be driven
by means of a speed-controlled motor that is connected to a control unit to which
measuring means are also connected to measure the abovementioned temperature at the
outlet of the condenser, for example in the form of a temperature sensor in the pipe
section between the expansion valve 21 and the condenser 20.
[0055] In a practical embodiment of the invention, the expansion valve 21 can be constructed
as a thermostatic or electronic valve and this valve 21 is connected to a temperature
sensor 23 that is positioned at the outlet 14 of the primary circuit.
[0056] According to the invention, the device is equipped with a controller 24 to control
the flow of the coolant, and the abovementioned controller 24 ensures the realisation
of the desired temperature or pressure dew point at the outlet 14 of the primary part
of the heat exchanger 12.
[0057] The controller 24 can thus control the speed of the drive 19, whereby a drive is
used in the form of a frequency-controlled motor, for example.
[0058] The controller 24 can also be used to control the motor of the fan 22 and/or to control
the expansion valve 21, and if applicable to also drive the drive 10 of the compressor
9.
[0059] It is clear that to control the temperature or pressure dew point, the control of
the drive 10 of the compressor 9 is one of the possibilities, but other arrangements
are also possible.
[0060] Between the outlet 11 of the compressor 9 and the inlet 13 of the primary part of
the heat exchanger 12, there is preferably an after-cooler 25 and a second water separator
26.
[0061] The method for making artificial snow by means of a device 1 according to the invention
is very simple and as follows.
[0062] A gas such as air is drawn into the compressor area 2 and compressed by the compressor
9. The hot compressed air is first driven through the after-cooler 25 and the second
water separator 26, after which this already partially cooled gas is guided through
the primary part of the heat exchanger 12, such that the compressed air at the outlet
14 of the primary part has an even lower temperature.
[0063] The condensate that is formed in the after-cooler 25 and the heat exchanger 12 is
separated in the respective liquid separators 26 and 15, and the cold less moist air
is then taken to the snow canon 6 via a pipe 7. In the snow cannon 6 the water will
be atomised by the cooled compressed air so that snow crystals are formed.
[0064] The cooling of the compressed air in the primary part of the heat exchanger 12 is
realised by driving a coolant through the secondary part of the heat exchanger 12.
Preferably this coolant flows in the opposite direction to the air that flows through
the primary part of this heat exchanger.
[0065] By passing through the secondary part, the abovementioned coolant is heated and then
cooled by the condenser 20, which in this case is placed immediately downstream from
the compressor element 18 in the cooling circuit 17.
[0066] The temperature of the coolant will then fall by flowing through the last-mentioned
condenser 20, as the fan 22 blows air over this condenser 20.
[0067] The air that is blown over the condenser 20 by the fan 22 is heated.
[0068] Because this warm air spreads through the entire compressor area 2, the temperature
in the compressor area 2 will always stay above freezing point.
[0069] The coolant that leaves the condenser 20 is then guided through the expansion valve
21, and then again to the inlet of the secondary part of the heat exchanger 12.
[0070] For the heat exchanger 12 and the cooling circuit 17 connected to it with the controller
24, a conventional cool dryer can be used if necessary, however the air-air recuperative
heat exchanger that is normally used in such a cool dryer is left out.
[0071] An advantage is that the device can be easily built from a compressor that is connected
to a suitable cool dryer which is available on the market.
[0072] The present invention is by no means limited to the embodiment described as an example
and shown in the drawing.
1. Device for making artificial snow by means of a snow cannon (6) in which water is
atomised by means of compressed air, whereby this device is provided with a compressor
(9) for supplying compressed air, which compressor (9) is positioned in a compressor
area (2) with an inlet (4) for supplying air from the environment and an outlet (5)
to deliver the compressed air to the snow cannon (6) via a pipe (7), wherein the above-mentioned
device (1) comprises a heat exchanger (12) with a primary part and a secondary part,
whereby the compressed air from the compressor (9) is guided through the primary part,
and whereby the abovementioned secondary part makes part of the evaporator (16) in
a closed cooling circuit (17) in which a coolant is circulated by means of a compressor
element (18) that is driven by a drive (19), characterised in that the abovementioned device includes a controller (24) for controlling the abovementioned
cooling circuit, in order to obtain a desired temperature or pressure dew point at
the outlet (14) of the primary part of the heat exchanger (12).
2. Device according to any one of the preceding claims, characterised in that at the outlet (14) of the primary part of the heat exchanger (12) is provided a liquid
separator (15) for removing the condensed water.
3. Device according to any one of the preceding claims, characterised in that the cooling circuit (17) comprises a heat exchanger (20) downstream from the compressor
element (18), which heat exchanger (20) forms the condenser of the cooling circuit
(17) and in that this heat exchanger (20) is cooled by means of a fan (22) blowing air over the heat
exchanger (20) in the compressor area (2).
4. Device according to any one of the preceding claims, characterised in that the compressor (9) compresses air that is drawn in from the compressor area (2).
5. Device according to any one of the preceding claims, characterised in that the controller (24) is such that the temperature at the outlet (14) of the primary
part is between 3° and 8° Celsius, preferably between 3° and 5° Celsius.
6. Device according to any one of the preceding claims, characterised in that the controller (24) is such that the temperature of the outlet (14) of the primary
part is 3° Celsius or around 3° Celsius.
7. Device according to any one of the preceding claims, characterised in that the controller (24) is such that a pressure dew point in the order of magnitude of
3° Celsius is realised.
8. Device according to any one of the preceding claims, characterised in that the compressor (9) is set to a maximum working pressure of 8.5 bar.
9. Device according to any one of the preceding claims, characterised in that the heat exchanger (12) is designed such that the pressure drop of the compressed
air over the primary part is less than 0.2 bar, or even better less than 0.1 bar,
and preferably less than 0.05 bar.
10. Device according to any one of the preceding claims, characterised in that the device (1) is mobile and housed in a container.
11. Device according to any one of the preceding claims, characterised in that the device (1) comprises a conventional cool dryer without recuperative heat exchanger.
12. Device according to any one of the preceding claims, characterised in that an after-cooler (25) is provided between an outlet (11) of the abovementioned compressor
(9) and an inlet (13) of the abovementioned primary part of the heat exchanger (12).
13. Device according to claim 12, characterised in that just downstream from the after-cooler (25) is provided a second liquid separator
(26).
1. Vorrichtung zur Herstellung von Kunstschnee mittels einer Schneekanone (6), worin
Wasser mittels verdichteter Luft vernebelt wird, wobei diese Vorrichtung mit einem
Verdichter (9) für die Zufuhr verdichteter Luft versehen ist, welcher Verdichter (9)
in einem Verdichterraum (2) mit einem Einlass (4) zur Zufuhr von Luft aus der Umgebung
und einem Auslass (5) zur Abfuhr der verdichteten Luft durch eine Leitung (7) zu der
Schneekanone (6) aufgestellt ist, wobei die vorgenannte Vorrichtung (1) einen Wärmetauscher
(12) mit einem Primärteil und einem Sekundärteil umfasst, wobei die verdichtete Luft
von dem Verdichter (9) durch den Primärteil geleitet wird und wobei der vorgenannte
Sekundärteil Teil des Verdampfers (16) in einem geschlossenen Kühlkreislauf (17) ist,
worin ein Kühlmittel mittels eines Verdichterelements (18), das durch einen Antrieb
(19) angetrieben wird, zirkuliert wird, dadurch gekennzeichnet, dass die vorgenannte Vorrichtung eine Steuerung (24) zur Steuerung des vorgenannten Kühlkreislaufs
umfasst, um an dem Auslass (14) des Primärteils des Wärmetauschers (12) eine gewünschte
Temperatur oder einen gewünschten Drucktaupunkt zu erhalten.
2. Vorrichtung nach einem der vorgenannten Ansprüche, dadurch gekennzeichnet, dass an dem Auslass (14) des Primärteils des Wärmetauschers (12) ein Flüssigkeitsabscheider
(15) zum Abführen des Kondenswassers vorgesehen ist.
3. Vorrichtung nach einem der vorgenannten Ansprüche, dadurch gekennzeichnet, dass der Kühlkreislauf (17) stromabwärts von dem Verdichterelement (18) einen Wärmetauscher
(20) umfasst, welcher Wärmetauscher (20) den Kondensator des Kühlkreislaufs (17) bildet,
und dass dieser Wärmetauscher (20) mittels eines Ventilators (22) gekühlt wird, der
Luft über den Wärmetauscher (20) in den Verdichterraum (2) bläst.
4. Vorrichtung nach einem der vorgenannten Ansprüche, dadurch gekennzeichnet, dass der Verdichter (9) Luft verdichtet, die aus dem Verdichterraum (2) angesaugt wird.
5. Vorrichtung nach einem der vorgenannten Ansprüche, dadurch gekennzeichnet, dass die Steuerung (24) derart ist, dass die Temperatur am Auslass (14) des Primärteils
zwischen 3° und 8° Celsius, bevorzugt zwischen 3° und 5° Celsius beträgt.
6. Vorrichtung nach einem der vorgenannten Ansprüche, dadurch gekennzeichnet, dass die Steuerung (24) derart ist, dass die Temperatur des Auslasses (14) des Primärteils
3° Celsius oder ungefähr 3° Celsius beträgt.
7. Vorrichtung nach einem der vorgenannten Ansprüche, dadurch gekennzeichnet, dass die Steuerung (24) derart ist, dass ein Drucktaupunkt in der Größenordnung von 3°
Celsius verwirklicht wird.
8. Vorrichtung nach einem der vorgenannten Ansprüche, dadurch gekennzeichnet, dass der Verdichter (9) auf einen maximalen Betriebsdruck von 8,5 bar eingestellt ist.
9. Vorrichtung nach einem der vorgenannten Ansprüche, dadurch gekennzeichnet, dass der Wärmetauscher (12) so gestaltet ist, dass der Druckabfall der verdichteten Luft
über den Primärteil weniger als 0,2 bar, oder noch besser weniger als 0,1 bar und
bevorzugt weniger als 0,05 bar beträgt.
10. Vorrichtung nach einem der vorgenannten Ansprüche, dadurch gekennzeichnet, dass die Vorrichtung (1) mobil und in einem Behälter untergebracht ist.
11. Vorrichtung nach einem der vorgenannten Ansprüche, dadurch gekennzeichnet, dass die Vorrichtung (1) einen herkömmlichen Kühltrockner ohne rekuperativen Wärmetauscher
umfasst.
12. Vorrichtung nach einem der vorgenannten Ansprüche, dadurch gekennzeichnet, dass ein Nachkühler (25) zwischen einem Auslass (11) des vorgenannten Verdichters (9)
und einem Einlass (13) des vorgenannten Primärteils des Wärmetauschers (12) vorgesehen
ist.
13. Vorrichtung nach Anspruch 12, dadurch gekennzeichnet, dass unmittelbar stromabwärts von dem Nachkühler (25) ein zweiter Flüssigkeitsabscheider
(26) vorgesehen ist.
1. Dispositif pour fabriquer de la neige artificielle au moyen d'un canon à neige (6)
dans lequel on atomise de l'eau au moyen d'air comprimé, ce dispositif étant équipé
d'un compresseur (9) pour l'alimentation d'air comprimé, ledit compresseur (9) étant
disposé dans une zone de compresseur (2) comportant une entrée (4) pour alimenter
de l'air depuis l'environnement et une sortie (5) pour distribuer l'air comprimé ou
canon à neige (6) via un conduit (7), le dispositif susmentionné (1) comprenant un
échangeur de chaleur (12) possédant une partie primaire et une partie secondaire,
l'air comprimé émanant du compresseur (9) étant guidé à travers la partie primaire,
et la partie secondaire susmentionnée faisant partie de l'évaporateur (16) dans un
circuit de refroidissement fermé (17) dans lequel on fait circuler un réfrigérant
au moyen d'un élément faisant office de compresseur (18) qui est entraîné par un entraînement
(19), caractérisé en ce que le dispositif susmentionné englobe un contrôleur (24) pour commander le circuit de
refroidissement susmentionné afin d'obtenir un point de rosée de température ou de
pression désiré à la sortie (14) de la partie primaire de l'échangeur de chaleur (12).
2. Dispositif selon l'une quelconque des revendications précédentes, caractérisé en ce qu'on prévoit, à la sortie (14) de la partie primaire de l'échangeur de chaleur (12),
un séparateur de liquide (15) pour éliminer l'eau condensée.
3. Dispositif selon l'une quelconque des revendications précédentes, caractérisé en ce que le circuit de refroidissement (17) comprend un échangeur de chaleur (20) en aval
de l'élément (18) faisant office de compresseur, ledit échangeur de chaleur (20) formant
le condenseur du circuit de refroidissement (17), et en ce que cet échangeur de chaleur (20) est refroidi au moyen d'un ventilateur (22) qui souffle
de l'air sur l'échangeur de chaleur (20) dans la zone (2) du compresseur.
4. Dispositif selon l'une quelconque des revendications précédentes, caractérisé en ce que le compresseur (9) comprime l'air qui est aspiré depuis la zone (2) du compresseur.
5. Dispositif selon l'une quelconque des revendications précédentes, caractérisé en ce que le contrôleur (24) est tel que la température à la sortie (14) de la partie primaire
se situe entre 3° et 8 °C, de préférence entre 3° et 5°C.
6. Dispositif selon l'une quelconque des revendications précédentes, caractérisé en ce que le contrôleur (24) est tel que la température de la sortie (14) de la partie primaire
s'élève à 3 °C ou à environ 3 °C.
7. Dispositif selon l'une quelconque des revendications précédentes, caractérisé en ce que le contrôleur 24 et telle que l'on obtient un point de rosée de pression dans l'ordre
de grandeur de 3 °C.
8. Dispositif selon l'une quelconque des revendications précédentes, caractérisé en ce que le compresseur (9) est réglé à une pression de travail maximal de 8,5 bars.
9. Dispositif selon l'une quelconque des revendications précédentes, caractérisé en ce que l'échangeur de chaleur (12) est conçu de telle sorte que la chute de pression de
l'air comprimé sur la partie primaire est inférieure à 0,2 bar ou encore mieux inférieure
à 0,1 bar et de préférence inférieure à 0,05 bar.
10. Dispositif selon l'une quelconque des revendications précédentes, caractérisé en ce que le dispositif (1) est mobile et logé dans un conteneur.
11. Dispositif selon l'une quelconque des revendications précédentes, caractérisé en ce que le dispositif (1) comprend un sécheur conventionnel à refroidissement par air en
l'absence d'un échangeur de chaleur de récupération.
12. Dispositif selon l'une quelconque des revendications précédentes, caractérisé en ce qu'on prévoit un refroidisseur final (25) entre une sortie (11) du compresseur susmentionné
(9) et une entrée (13) de la partie primaire susmentionnée de l'échangeur de chaleur
(12).
13. Dispositif selon la revendication 12, caractérisé en ce qu'on prévoit, juste en aval par rapport au refroidisseur final (25), un deuxième séparateur
de liquide (26).