US20090114735A1

US20090114735A1 - Snowmaking methods

Info

Publication number: US20090114735A1
Application number: US12/264,389
Authority: US
Inventors: Jay H. COLLINS
Original assignee: Johnson Controls Technology Co
Current assignee: Johnson Controls Technology Co
Priority date: 2007-11-05
Filing date: 2008-11-04
Publication date: 2009-05-07
Also published as: WO2009061722A2; WO2009061722A3

Abstract

A method and apparatus for producing artificial snow is provided. The method and apparatus include controls and operating parameters for given ambient conditions to assure that fluid droplets are at equilibrium temperature before mixing with ice nuclei to produce artificial snow.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority from and the benefit of U.S. Provisional Application No. 60/985,481 entitled SNOWMAKING METHODS, filed Nov. 5, 2007, which is hereby incorporated by reference.

BACKGROUND

The application generally relates to snowmaking. The application relates more specifically to a method and apparatus for producing artificial snow.
Snowmaking is critical to winter sporting resorts because the amount of snow and the length and period of time that snow is present dictate whether a resort has a financially successful season. Generally, as the amount of snow increases, so does the length of time the snow is present. The earlier and the longer the length of time snow is present, the longer skiers, snowboarders, and the like are able to use a resort. However, unpredictable weather patterns can produce winters with low outputs of natural snow.
Therefore, winter sporting resorts have long recognized the need for making artificial snow. However, snowmaking is often capital and labor intensive for the resort. Generally, two different types of snowmaking systems are used, namely, airless systems and air (i.e., air/water) systems. Typically, in an air/water system, a ski resort has a water pumping center and an air compressor located near the base of the resort, e.g., at a lake or pond. From the center, water and air lines run uphill along the ski slopes. At various locations, provision is made for tapping into the air and water lines. In an airless system, pressurized water lines and electrical lines or other motorized means to power the snowmaking machine are used to make snow.
An example air/water system is a snowgun that includes a nozzle that combines high amounts of compressed air and relatively low amounts of pressurized water. The compressed air and pressurized water are simultaneously discharged from the snowgun. As the compressed air and pressurized water exit the snowgun, the expansion of air creates frozen nuclei, breaks up the water into smaller particles, and propels it across the slope. Cold ambient air completes the freezing process and causes the water to form into artificial snow. However, such gun designs produce relatively little snow despite the large amounts of air used. The high cost of producing compressed air is a disadvantage of this type of system. Such air/water systems are usually ineffective above 28 degrees Fahrenheit (−2 degrees Celsius) (wetbulb), and their maximum output is typically 17 to 20 gallons/minute (64-76 liters/minute) at 28 degrees Fahrenheit (−2 degrees Celsius) (wetbulb).
An example airless system is a low-pressure snow cannon that includes a propeller (e.g., a fan) for producing a main air stream into which freezing nuclei are sprayed by means of nucleator nozzles and small water droplets are spayed by means of water nozzles. The nucleator nozzles are constructed as water/air nozzles, and they are operated with compressed air and water under pressure and atomize a water/air mixture. The compressed air relaxes as it issues from the nucleator nozzles and thus cools water droplets of the water/air mixture to well below the freezing point so that small ice crystals are formed. The droplets discharged by the water nozzles collide and/or intersect with these freezing nuclei and form snow crystals. Although such snow cannons generally have a greater output than snowguns, they also are usually ineffective above 28 degrees Fahrenheit (−2 degrees Celsius) (wetbulb).
Current meteorological evidence indicates that, on average, the global climate is warming. Winters are becoming shorter, as well as the length of the skiing season. The amount of natural snow falling at winter sporting resorts is also declining. It is estimated that a 1 degree Celsius increase in average temperature will reduce the length of the skiing season by about 25%. It is therefore important for winter sporting resorts to be able to make snow at higher temperatures and to make greater amounts of artificial snow when ambient weather conditions permit.
Intended advantages of the disclosed methods satisfy one or more of these needs or provide other advantageous features. Other features and advantages will be made apparent from the present specification. The teachings disclosed extend to those embodiments that fall within the scope of the claims, regardless of whether they accomplish one or more of the aforementioned needs.
In an embodiment, a control system is provided that monitors snowmaking conditions (ambient temperature, relative humidity, etc.), as well as operational parameters (electric power supply, water supply, etc.), and operates a snowmaking device in accordance with pre-programmed parameters or instructions to maximize snow production.

SUMMARY

In one embodiment of the disclosure, a method of producing artificial snow is disclosed that includes providing a mass of propelled fluid through a housing having an inlet and an outlet, injecting a spray of liquid droplets into the propelled fluid, and injecting ice crystals and additional liquid droplets into the mass of propelled fluid from a structure disposed within the housing proximate the outlet.
Alternative exemplary embodiments relate to other features and combinations of features as may be generally recited in the claims.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 illustrates an exemplary arrangement of a snowmaking apparatus providing artificial snow to a ski area.

FIG. 2 illustrates a side view of an exemplary snowmaking apparatus according to the disclosure.

FIG. 3 illustrates a second side view of the snowmaking apparatus of FIG. 2.

FIG. 4 is an illustration of support components of the snowmaking apparatus of FIGS. 2 and 3.

FIG. 5 is a top view of a housing of the snowmaking apparatus of FIGS. 2 and 3.

FIG. 6 is an inlet end view of the housing of the snowmaking apparatus of FIGS. 2 and 3.

FIG. 7 is a cross sectional view of the housing of FIG. 5 taken along line 7-7.

FIG. 8 is a cross sectional view of the housing of FIG. 5 taken along line 8-8.

FIG. 9 is an outlet end view of the housing of the snowmaking apparatus of FIGS. 2 and 3.

FIG. 10 is a perspective view of a structure located in an embodiment of a snowmaking apparatus.

FIG. 11 is an enlarged partial perspective view of a portion of the structure of FIG. 10.

FIG. 12 is a perspective front view of an exemplary snow particle generator.

FIG. 13 is a perspective front view of an exemplary nozzle.

FIG. 14 is a side view of the structure of FIG. 10.

FIG. 15 is a top view of the structure of FIG. 10 taken along line 15-15.

FIG. 16 is an end view of the structure of FIG. 10.

FIG. 17 is a bottom view of the structure of FIG. 10 taken along line 17-17.

FIG. 18 is a cross-sectional view of the structure of FIG. 10 taken along line 18-18.

FIG. 19 is a sectional view of an exemplary outer ring system of the snowmaking apparatus of FIGS. 2 and 3.

FIG. 20 is top view of an exemplary manifold of the snowmaking apparatus of FIGS. 2 and 3.

FIG. 21 is a front view of the manifold of FIG. 20.

FIG. 22 is a bottom view of the manifold of FIG. 20

FIG. 23 is a side view of the manifold of FIG. 20.

FIG. 24 is an illustration of an exemplary water spray pattern from a snow cannon during operation according to the disclosure.

DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS

FIG. 1 illustrates an exemplary arrangement of a ski area 1 having at least one snowmaking apparatus 10 arranged to produce artificial snow 11 on ski area 1. The snowmaking apparatus 10 is connected to a source 16 of pressurized liquid and compressed fluid. The pressurized liquid and compressed fluid may be provided from various locations at or near ski area 1. The placement and number of snowmaking apparatus 10 is exemplary, and any number and placement of snowmaking apparatus 10 may be arranged to meet snow coverage demands of ski area 1.
In one embodiment, the pressurized liquid may be water and the compressed fluid may be air. However, the liquid and fluid are not limited to water and air, respectively. That is, both liquid and fluid may be composed partially or entirely of materials other than water and air. The term ice, as used herein, refers to a solid state of a substance resembling ice, and is not limited to water in a solid state.
FIGS. 2 and 3 show an exemplary snowmaking apparatus 10 according to the disclosure. Snowmaking apparatus 10 includes a housing 36 having an inlet 54 and an outlet 56. A fluid is introduced into inlet 54 and propelled by an fluid moving device 51 (FIG. 6) disposed within housing 36 to exit through outlet 56 as indicated by fluid direction arrow 74. Snowmaking apparatus 10 further includes a screen 34 mounted over inlet 54 to prevent debris and/or access to the interior of housing 36. In another embodiment, screen 34 may be omitted.
As shown in FIG. 3, housing 36 is mounted upon support assembly 50 at connection points 52. Connection points 52 are configured to permit housing 36 to rotate about connection points 52 as indicated by arrows B by operation of an elevator arm 42. Support assembly 50 is rotatably mounted in the horizontal plane upon chassis 12 at pivot point 48. In one embodiment, support assembly 50 may be mounted to a turntable (not shown) that overlies and is rotatably mounted to chassis 12 such that support assembly 50, and thus also housing 36, collectively rotate about an axis 48 as indicated by arrows C. Pivot point 48 should be sufficiently strong to support at least several hundred pounds, yet rotatable about its central axis 47 as indicated by arrows C. A motor 44 (FIG. 4), which is connected to pivot point 48 by reciprocating arm 46, rotates support assembly 50, and thus housing 36, about axis 47. Stated another way, housing 36 may be selectively rotated to affect pitch and yaw with respect to chassis 12. The resulting adjustable movement about different axis of rotation of snowmaking apparatus 10 permits snow to be distributed through a broad predetermined range.
Referring to FIGS. 2, 3 and 4, snowmaking apparatus 10 further includes support components 14 including tires 16, drop jacks 28, and support brackets 24. Snowmaking apparatus 10 may be maneuvered into a position alongside a ski trail or other location by raising drop jacks 28, pulling snowmaking apparatus 10 into location, and lowering drop jacks 28. Drop jacks 28 are operated by hand crank 30, which may be operated in order to support chassis 12 of snowmaking apparatus 10 in a level position. Low-pressure tires 16 are attached to chassis 12 by single-pin quick release tire locks 32, which permit the rapid replacement of tires 16 without the need for tools. Snowmaking apparatus 10 also includes an emergency light 20, a utility light 22, an automated valve assembly 18, a control panel 15, a control cable 40, a hose 38, a compressor 26, and various other components. In this exemplary embodiment, compressor 26 is mounted upon support assembly 50, however, in alternative embodiments, compressor 26 may be located remote from the snowmaking apparatus 10 and provided with hoses, piping or other fluid communication structures to provide compressed fluid to the snowmaking apparatus.
FIG. 5 illustrates a top view of housing 36. Housing 36 includes inlet 54 protected by screen 34 and outlet 56. Housing 36 is tapered from inlet 54 to outlet 56. Housing 36 is sufficiently long to substantially prevent unproductive recirculation of fluid from outlet 56 back to inlet 54. Housing inlet 54 is flared. Although cylindrical housing 36 is shown as being cylindrical, one skilled in the art will appreciate that other similar geometric forms may also be used.
FIGS. 6, 7 and 8 illustrate various components within housing 36. FIG. 6 is an end view taken of the interior of housing 36 with screen 34 removed for clarity. FIG. 7 is an end view taken of outlet 56 of housing 36. FIG. 8 is a cross-sectional view of housing 36. As can be seen in FIGS. 6, 7 and 8, housing 36 has a fluid moving device 51 disposed therein. Fluid moving device 51 may be a fan 58 rotatably attached to a fan motor 68. Fan 58 induces fan blades 60. Fan motor 68 rotates fan blades 60 in the direction noted by fan rotation direction arrow 76. Fan motor 68 is mounted on a fan motor support 66 and mounting bracket 64. Curved straightening vanes 62 are located behind fan blades 60 and compensate for any swirling motion of the fluid that may be caused by fan blades 60. Fan motor power supply 70 provides electric power to fan motor 68 and grease leads 72 permit lubrication of the components of fan motor 68 without having to disassemble snowmaking apparatus 10. Fan 58 propels fluid through housing 36 at a rate between about 12,000 cubic feet per minute (cfm) and about 14,000 cfm. In other embodiments, the amount of fluid propelled through housing 36 may fall outside the about 12,000 cfm to about 14,000 cfm range. In yet another embodiment, the amount of fluid propelled through housing 36 may be at a rate of between about 6,000 cfm to about 25,000 cfm. In still yet another embodiment, the amount of fluid propelled through housing 36 may be at a rate of between about 10,000 cfm to about 20,000 cfm.
FIG. 9 illustrates an end view of outlet 56. As can be seen in FIG. 9, the housing 36 further includes a structure 84 secured to a manifold 81 and a distribution system 85. In one embodiment, structure 84 and distribution system 85 are formed of a metal alloy. In another embodiment, structure 84 and distribution system 85 are formed of an aluminum alloy.
The distribution system 85 includes a plurality of peripheral nozzles 78, such as V-jet nozzles, arranged concentrically in three concentric circles at outlet 56 of housing 36. In one embodiment, nozzles 78 may be arranged in one, two, three or more than three concentric circles. In another embodiment, nozzles 78 may be arranged in two concentric circles. Distribution system 85 is in fluid communication with a pressurized liquid supply through a valve assembly 82 and a manifold 81 attached to a rear surface (not shown) of distribution system 85. In one embodiment, the peripheral nozzles 78 in distribution system 85 are inclined inward at an angle between about 5 degrees and about 85 degrees so that during operation of snowmaking apparatus 10 the spray pattern of each nozzle 78 is directed into the fluidflow exiting housing 36 to inject the formed liquid droplets into the fluidflow. In another embodiment, the peripheral nozzles 78 in distribution system 85 are inclined inward at an angle between about 5 degrees and about 25 degrees. In another embodiment, the peripheral nozzles 78 are inclined inward at an angle between about 10 degrees to about 20 degrees. In another embodiment, the nozzles 78 are inclined inward at an angle of about 15 degrees. In one embodiment, the distribution system 85 has three concentric circles of nozzles 78, and the nozzles 78 on the inside circle are inclined inward at an angle between about 10 degrees and about 18 degrees, and preferably about 12 degrees, and the nozzles 78 on the middle circle are inclined inward at an angle between about 8 degrees and about 15 degrees, and preferably about 10 degrees, and the nozzles 78 on the outside ring are inclined inward at an angle between about 5 degrees and about 10 degrees, and preferably about 8 degrees. For reference, a 0 degree inclination would be parallel to the fluidflow, and a 90 degree inclination would be perpendicular to and directed inwardly towards the fluidflow.
In one embodiment, nozzles 78 produce a flat spray pattern in the shape of a triangle having a spray angle of between about 15 degrees to about 65 degrees. In another embodiment, the spray angle is between about 25 degrees and about 50 degrees. In another embodiment, nozzles 78 produce a flat spray pattern in the shape of a triangle having a spray angle of between about 25 degrees to about 40 degrees. In yet another embodiment, nozzles 78 produce a flat spray pattern in the shape of a triangle having a spray angle of about 25 degrees. In still another embodiment, the spray pattern may be in a shape other than a flat triangle, for example, the spray pattern may be a hollow conical or cylindrical shaped pattern.
During operation of snowmaking apparatus 10, liquid is supplied to nozzles 78 under a pressure between about 100 pounds per square inch (psi) and 600 psi to form liquid droplets, which are injected into the propelled fluid. The nozzles 78 are configured to produce water droplets having a mean droplet size for a particular water pressure. Nozzles 78 may be selected to produce droplets having mean droplet sizes of between about 200 microns to about 1000 microns. In another embodiment, nozzles 78 are selected to produce droplets having a mean droplet size of between about 300 microns to about 900 microns. The droplet size may increase in this range as ambient temperature decreases. Droplet size less than 200 microns may not have enough mass after evaporative cooling to effectively form snow at the point of mixing with the ice nuclei. Also, droplet size of less than 200 microns may allow wind conditions and convective air currents to adversely affect the ability to direct snow production to a desired area. Droplet size of greater than 1000 microns produce a less desirable ski surface.
An additional parameter necessary to snow formation is the ratio of ice nuclei to water droplets. It has been determined that a ratio of ice nuclei to water droplets in a range of about 0.7:1 to about 1.2:1 resulted in improved conversion of bulk water to snow for snowmaking. In one embodiment, it has been determined that a ratio of ice nuclei to water droplets greater than or equal to 1:1 results in improved conversion of bulk water to snow for snowmaking.
In one embodiment, water droplets are sprayed out of nozzles 78 under pressure of about 300 pounds per square inch (2067 kilopascals). The volume of flow, droplet size and number of droplets of liquid from the nozzles 78 may be controlled by valves incorporated into the individual nozzles 78, or the nozzles 78 may be controlled only by the flow of pressurized fluid in the manifold, or a combination thereof. By controlling the flow of liquid from the nozzles 78, the amount of bulk water used to form snow may be controlled. A plurality of peripheral V-jet nozzles 78 are arranged in three concentric circles forming outer ring system 85 at the circumference of cylindrical housing outlet 56, where they are in fluid communication with a pressurized water supply.
In another embodiment, liquid is supplied to nozzles 78 under a pressure between about 175 pounds per square inch (psi) and 600 psi to form liquid droplets, which are injected into the propelled fluid. In another embodiment, liquid is supplied to nozzles 78 at a pressure of between about 250 psi and about 500 psi. In yet another embodiment, liquid is supplied to the nozzles 78 at a pressure of about 300 psi.
Still referring to FIG. 9, structure 84 is located proximate outlet 56 and projects radially inward from housing 36. Structure 84 includes three nozzles 78, which are the same as peripheral nozzles 78 in distribution system 84. Nozzles 78 located on structure 84 further inject liquid droplets into the fluidflow. These nozzles 78 may also be referred to as axial nozzles 78. Structure 84 further includes three snow particle generators 80, otherwise known as nucleators, which operate in a range of about 90 psi to about 120 psi, for injecting ice particles into the fluidflow. Nozzles 78 and snow particle generators 80 are in fluid communication with valve assembly 82 via manifold 81. Manifold 81 provides pressurized liquid at between about 200 psi to about 600 psi to structure 84 for distribution to nozzles 78 and snow particle generators 80 disposed thereon. Manifold 81 also provides pressurized liquid at between about 200 psi to about 600 psi to distribution system 85. During operation, liquid droplets sprayed under pressure from the axial nozzles 78 impinge upon liquid droplets sprayed from the peripheral nozzles 78, and the resulting sheer stresses cause the liquid droplets to further fragment thereby facilitating nucleation. In one embodiment, the spray pattern of the nozzles 78 in the structure 84 and the distribution system 85 may vary. In one embodiment, the spray pattern of the nozzles 78 on the structure 84 may be between about 15 degrees and about 65 degrees. In another embodiment, the spray pattern of the nozzles 78 on the structure 84 may be between about 25 degrees and about 50 degrees. In yet another embodiment, the spray pattern of the nozzles 78 on the structure 84 may be between about 25 degrees and about 40 degrees. In another embodiment, the spray pattern of the nozzles 78 on the structure 84 may be about 25 degrees. In yet another embodiment the nozzles 78 in the structure 84 may produce a hollow conical or cylindrical spray pattern. In still another embodiment, the spray pattern of the nozzles 78 on the structure 84 may be about 65 degrees and the spray pattern of the nozzles 78 on the distribution system 85 may be between about 40 degrees and about 50 degrees.
FIG. 10 is a perspective view of structure 84. As can be seen in FIG. 10, structure 84 is tapered toward the interior of housing 36 to facilitate fluidflow around structure 84 during operation of snowmaking apparatus 10 and to prevent unproductive fluid swirling motions near snow particle generators 80 which prevents the snow particle generators from icing. The tapered geometry also provides an airstream around the snow particle generators, which improves the mixing of the ice particles into the fluidflow. In the exemplary embodiment, three axial nozzles 78 and three snow particle generators 80 are mounted on a surface of structure 84 oriented away from the interior of housing 36 in the same direction as fluidflow direction arrow 74 (FIG. 8). In another embodiment, the structure 84 may include one or more axial nozzles 78 and one or more snow particle generators 80. FIG. 11 is an enlarged view of structure 84 showing snow particle generator 80 and nozzle 78 disposed on structure 84.
FIG. 12 illustrates an enlarged, more detailed view of an exemplary snow particle generator 80. Snow particle generator 80 includes a threaded connection 86, which connects snow particle generator 80 to structure 84, and O-rings 88, which provide a sealing connection to liquid and fluid conduits or channels within structure 84. Snow particle generator 80 further includes a filter screen 90 and an outlet 92. Liquid enters snow particle generator 80 through filter screen 90, and fluid enters through inlet 98. Filter screen 90 prevents liquid-bourn debris from entering snow particle generator 80 and thereby obstructing outlet 92. Within snow particle generator 80, pressurized fluid and liquid are mixed and then expelled from outlet 92 in the form of a fog or cloud of small ice particles. A detailed description of snow particle generator 80 is disclosed in U.S. Pat. No. 6,508,412, which is incorporated herein in the entirety by reference.
FIG. 13 illustrates an enlarged, more detailed view of exemplary nozzle 80. Nozzle 80 includes a threaded connection 94, which connects nozzle 80 to structure 84, an inlet 97 and an outlet 99. Fluid enters nozzle 80 through inlet 97 and exits nozzle 80 through outlet 99 in a flat spray pattern having an angle 96.
FIGS. 14 and 16 illustrate a side and a front view, respectively, of structure 84. Additionally, FIGS. 15 and 17 illustrate of a top cut-away view and bottom view of structure 84, respectively. As can be seen in FIGS. 15 and 17, at least one liquid channel 100 and a compressed fluid channel 102 are disposed within structure 84. Fasteners 104 fasten structure 84 to manifold 81 (FIG. 9). Fasteners 104 may include any permanent or removable secure mechanical connection, such as bolts, wing nuts, clasps and clamps. In another embodiment, structure 84 may be assembled to manifold 81 by welding, gluing or other joining method. A removable fastener 104 facilitates routine maintenance, cleaning, and repair. Gaskets 104 are disposed around the fasteners 104 to provide a seal. A gasket 124 is provided between structure 84 and manifold 81 to provide a seal. A liquid conduit 106 distributes liquid from manifold 81 to liquid channel 100.
FIG. 18 is a cross-sectional view of structure 84. As can be seen in FIG. 18, at least one liquid channel 100 provides pressurized liquid to nozzles 78 and snow particle generators 80 disposed on structure 84. In this exemplary embodiment, at least one liquid channel 100 includes a front liquid channel 100A and a rear liquid channel 100B disposed in proximity and on opposite sides of compressed fluid channel 102. In another embodiment, structure 84 may include two or more liquid channels 100. The pressurized liquid in liquid channels 100A, 100B prevents icing in the compressed fluid channel 102 during operation. Snow particle generators 80 are provided with compressed fluid by compressed fluid channel 102. Snow particle generators 80 and nozzles 78 are thus in fluid communication with a central pressurized liquid supply (not shown) via fluid channel 100. Compressed fluid channel 102 is in fluid communication with compressor 26 (FIG. 2) via compression lines (not shown).
FIG. 19 is a schematic illustration of a cut-away view an exemplary distribution system 85. Distribution system 85 includes a front ring panel 86 (FIG. 9) and a rear ring panel (not shown). Front ring panel 86 and rear ring panel are joined together to define an inner liquid channel or ring 108, a middle liquid ring 110, and an outer liquid ring 112. Inner liquid ring 108, middle liquid ring 110 and outer liquid ring 112 may be formed by machining or otherwise forming a groove in front ring panel 86, rear ring panel, or both front ring panel 86 and rear ring panel. An inner sealing ring 114 and outer sealing ring 116 are disposed between front ring panel 86 and rear ring panel to prevent liquid leakage from distribution system 85. Fasteners 118 are provided to hold front ring panel 86 and rear ring panel in physical contact. Fasteners 118 may be spot welds, nuts, bolts, or other permanent or removable fastener.
Inner liquid ring 108 is in fluid communication with inner ring peripheral nozzles 78A, middle liquid ring 110 is in fluid communication with middle ring peripheral nozzles 78B, and outer liquid ring 112 is in fluid communication with outer ring peripheral nozzles 78C. Inner liquid ring 108 is also in fluid communication with inner fluid ring connection 126A, middle fluid ring 110 is also in fluid communication with middle fluid ring connection 126B, and outer fluid ring 112 is also in fluid communication with outer fluid ring connection 126C. In one exemplary embodiment peripheral nozzles 78A, 78B, and 78C are radially oriented inward towards housing central axis 121 along spray direction 120 by an inclination angle as discussed above.
In an alternative embodiment, liquid rings 108, 110, and 112 are each made from three independent circular pipes (not shown) that form distribution system 85. In yet another embodiment, each of three liquid rings 108, 110, and 112 may be operated independently of one another, with or without simultaneous operation of structure 84.
FIG. 20 shows a top view of manifold 81. As can be seen in FIG. 20, manifold 81 includes a liquid channel 110 that provides pressurized liquid to liquid channel 100A of structure 84 (FIG. 18). Liquid channel 110 also provides pressurized liquid to liquid reservoir 106, which provides pressurized liquid to liquid channel 100A of structure 84 (FIG. 18). The manifold 81 further includes a compressed fluid channel 102 a, which is in fluid communication with compressed fluid channel 102 of structure 84 (FIG. 18), and fasteners 104 for joining manifold 81 with structure 84 (FIG. 18).
FIG. 21 shows a front view of manifold 81 taken where manifold 81 is joined to the outer ring system 85. Referring to FIGS. 19 and 21, manifold 81 further includes additional liquid channels 110. The liquid channels 110, labeled liquid channels 110 b and 110 c, along with liquid channel 110 a, are in fluid communication with middle liquid ring connection 126B, and outer liquid ring connection 126C, and inner liquid ring connection 126A. FIG. 21 also shows fasteners 104, which join manifold 81 to outer ring system 85 (FIG. 19).
FIG. 22 shows a bottom view of manifold 81. As can be seen in FIG. 22, manifold 81 includes a bottom surface 81C having access to liquid channels 110 and fluid channel 102 a. The manifold bottom surface 81C is corresponds to a top surface (not shown) of valve assembly 82 (FIG. 9), which provides a pressurized liquid and compressed fluid to liquid channels 110 and fluid channel 102A, respectively.
In one embodiment, valve assembly 82 is configured to regulate pressurized liquid to the middle liquid ring connection 126B and inner liquid ring connection 126A while permitting pressurized liquid to flow to the structure 85 and outer liquid ring connection 126C unregulated, or in other words, without valving.
FIG. 23 shows a side view of manifold 81. As can be seen in FIG. 23, manifold 81 includes additional fasteners 104 for assembling manifold 81 to housing 36.
FIG. 24 is a schematic illustration of an exemplary liquid/ice/snow spray pattern 100 of snowmaking apparatus 10 during operation. As can be seen in FIG. 24, nozzles 78 on distribution system 85 and structure 84 and snow particle generators on structure 84 contribute to the liquid/ice/snow spray pattern 100 to form artificial snow. Whereas most existing snowmaking apparatus at 28 degrees Fahrenheit (−2 degrees Celsius) (wet bulb) can process a maximum (max) 15-20 gallons/minute (gal/min) into artificial snow, in one embodiment, snowmaking apparatus 10 has formed up to about 30 gal/min maximum at 28 degrees F. (wet bulb) and up to about 140 gal/min max at 18 deg. F. (wet bulb) into snow. In another exemplary embodiment, snowmaking apparatus 10 forms up to about 150 gal/min at 18 degrees F. (wet bulb) into snow. In yet another exemplary embodiment, a snowmaking apparatus 10 having a structure 84 having three particle generators 80 and two nozzles 78 and no distribution system 85, formed snow at between about 8 gal/min to about 39 gal/min max, at any wet bulb temp below 32 degrees F.
While only certain features and embodiments of the invention have been illustrated and described, many modifications and changes may occur to those skilled in the art (for example, variations in sizes, dimensions, structures, shapes and proportions of the various elements, values of parameters, such as, but not limited to temperatures, pressures, mounting arrangements, use of materials, colors, orientations, etc., without materially departing from the novel teachings and advantages of the subject matter recited in the claims. The order or sequence of any process or method steps may be varied or re-sequenced according to alternative embodiments. It is, therefore, to be understood that the appended claims are intended to cover all such modifications and changes as fall within the true spirit of the invention. Furthermore, in an effort to provide a concise description of the exemplary embodiments, all features of an actual implementation may not have been described (that is, those unrelated to the presently contemplated best mode of carrying out the invention, or those unrelated to enabling the claimed invention). It should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation specific decisions may be made. Such a development effort might be complex and time consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure, without undue experimentation.

Claims

1. A method for producing artificial snow, comprising:

providing a mass of propelled fluid through a housing having an inlet and an outlet;

injecting a spray of liquid droplets into the propelled fluid; and

injecting ice crystals and additional liquid droplets into the mass of propelled fluid from a structure disposed within the housing proximate the outlet.

2. The method of claim 1, wherein the spray of liquid droplets is injected into the propelled fluid from a circumferential position proximate the housing outlet.

3. The method of claim 1, wherein the liquid droplets have a mean particle size between about 200 microns and about 1000 microns.

4. The method of claim 1, wherein the liquid droplets have a mean particle size of between about 300 microns and about 900 microns.

5. The method of claim 1, wherein the mass of propelled fluid is provided at between about 6,000 cfm and about 25,000 cfm.

6. The method of claim 1, wherein the additional liquid droplets are injected into the propelled fluid at an inclination angle of between about 5 degrees to about 85 degrees.

7. The method of claim 1, wherein the additional liquid droplets are injected into the propelled fluid at an inclination angle of between about 10 degrees to about 20 degrees.

8. The method of claim 1, wherein the additional liquid droplets are injected into the propelled fluid from at least two concentric circles surrounding the perimeter of the propelled fluid.

9. The method of claim 8, wherein the additional liquid droplets are injected into the propelled fluid from three concentric liquid rings.

10. The method of claim 8, wherein the three concentric rings inject fluid from an inner liquid ring having a nozzle at an inclined angle between about 10 degrees and about 18 degrees, a middle liquid ring having a nozzle at an inclined angle between about 8 degrees and about 15 degrees, and an outer liquid ring having nozzle at an inclined angle between about 5 degrees and about 10.

11. The method of claim 1, wherein the spray of additional liquid droplets are injected with a flat triangular spray pattern of about 15 degrees to about 65 degrees.

12. The method of claim 1, wherein the spray of additional liquid droplets are injected with a flat triangular spray pattern of about 25 degrees to about 50 degrees.

13. The method of claim 1, wherein the ratio of liquid droplets and additional liquid droplets to ice crystals is about 0.7:1.

14. The method of claim 1, wherein the ratio of liquid droplets and additional liquid droplets to ice crystals is between about 0.7:1 to about 1.2:1.

15. The method of claim 1, wherein the liquid droplets, additional liquid droplets and ice crystals inject a liquid into the propelled fluid at a rate of up to about 150 gal/min at 18 degrees F. (wet bulb).