Patent Description:
Refrigeration systems are often used to provide cooling to temperature controlled display devices (e.g., cases, merchandisers, etc.) in supermarkets and other similar facilities. Vapor compression refrigeration systems are a type of refrigeration system which provide such cooling by circulating a fluid refrigerant (e.g., a liquid and/or vapor) through a thermodynamic vapor compression cycle. In a vapor compression cycle, the refrigerant is typically (<NUM>) compressed to a high temperature/pressure state (e.g., by a compressor of the refrigeration system), (<NUM>) cooled/condensed to a lower temperature state (e.g., in a gas cooler or condenser which absorbs heat from the refrigerant), (<NUM>) expanded to a lower pressure (e.g., through an expansion valve), and (<NUM>) evaporated to provide cooling by absorbing heat into the refrigerant. <CIT>discloses an apparatus and method to cool compressors, condensing coils, and similar devices. The compressor or condensing coil is cooled by the delivery of water, which may be ambient temperature or chilled. In one embodiment, the water is delivered to a mesh filter or screen via one or more mist spray nozzles. Water conduits may be integrated with the filter frame. The method to control the delivery of the water is designed to conserve water. The control circuit comprises a microcontroller device which contains programming that receives inputs, including but not limited to, outside ambient air temperature, condenser liquid line temperature, relative humidity and electric current, and uses said inputs to provide a stepwise level of control ("solenoid open time") of water delivery commensurate with outside air temperature and relative humidity.

According to the invention there is provided a cooling device, a CO<NUM> refrigeration system and a method of providing an evaporative gas cooler for a refrigeration system as defined by the appended claims.

Following below are more detailed descriptions of various concepts related to, and implementations of, methods, apparatuses, and for providing cooling using an evaporative cooling device. The various concepts introduced above and discussed in greater detail below may be implemented in any of a number of ways, as the described concepts are not limited to any particular manner of implementation. Examples of specific implementations and applications are provided primarily for illustrative purposes.

Providing a target, such as a temperature controlled case, with cooling is often performed in order to store products, such as refrigerated goods or frozen goods, in the target. In some applications, the target is cooled by a cooling system which circulates a refrigerant through a circuit path and includes a gas cooler for cooling or condensing a high-temperature refrigerant. The gas cooler may include heat exchanger coils and moisture pads. The moisture pads may be wetted with a device which drips water down through the moisture pads.

In some situations, the cooling systems generate excess water and runoff from the moisture pads which may be drained or recirculated back to drip-emitters at the top of the moisture pads. For example, the water flowing through the moisture pads may not be completely absorbed by the moisture pads or evaporated by the airflow drawn through the pads. As a result, the amount of water necessary for the moisture pads to be adequately wetted and able to provide sufficient cooling may require excess water to flow through the moisture pads. In another situation, spraying water droplets on the moisture pads may cause water to "blow-through" the moisture pad, which decreases efficiency and creates excess runoff, which may result in coil saturation, which leads to formation of scale, corrosion materials, etc..

Implementations described herein are related to a cooling device for a refrigeration system. The cooling device includes a water supply line feeding electrostatic spray nozzles that atomize the water droplets and electrostatically charge the droplets. Electrostatically charging the droplets may provide improved moisture pad coverage and water retention on the moisture pads, as the droplets are capable of being attracted to oppositely charged moisture pads. The cooling device may include a moisture sensing element which provides a feedback signal to a variable flowrate control device on the water supply line to the nozzles to minimize water usage and runoff.

Referring generally to the FIGURES, the refrigeration system is shown by way of examples as a CO<NUM> refrigeration system and components thereof, according to various exemplary embodiments. The CO<NUM> refrigeration system may be a vapor compression refrigeration system which uses primarily carbon dioxide (i.e., CO<NUM>) as a refrigerant. In some implementations, the CO<NUM> refrigeration system may be used to provide cooling for temperature controlled display devices in a supermarket or other similar facility. The CO<NUM> refrigeration system can include a CO<NUM> refrigerant circuit. The CO<NUM> refrigerant circuit can include evaporators, low-temperature (LT) and medium-temperature (MT) compressors, gas coolers, a receiver, and expansion valves. The CO<NUM> refrigerant circuit can be configured to circulate CO<NUM> as a refrigerant to provide cooling to the evaporators.

In some embodiments, the CO<NUM> refrigeration system includes a receiving tank (e.g., a flash tank, a refrigerant reservoir, etc.) containing a mixture of CO<NUM> liquid and CO<NUM> vapor, a gas bypass valve, and a parallel compressor. The gas bypass valve may be arranged in series with one or more MT compressors of the CO<NUM> refrigeration system. The gas bypass valve provides a mechanism for controlling the CO<NUM> refrigerant pressure within the receiving tank by venting excess CO<NUM> vapor to the suction side of the CO<NUM> refrigeration system MT compressors. The parallel compressor may be arranged in parallel with both the gas bypass valve and with other compressors of the CO<NUM> refrigeration system. The parallel compressor provides an alternative or supplemental means for controlling the pressure within the receiving tank.

Advantageously, the CO<NUM> refrigeration system includes a controller for monitoring and controlling the pressure, temperature, and/or flow of the CO<NUM> refrigerant throughout the CO<NUM> refrigeration system. The controller can operate both the gas bypass valve and the parallel compressor (e.g., according to the various control processes described herein) to efficiently regulate the pressure of the CO<NUM> refrigerant within the receiving tank. Additionally, the controller can interface with other instrumentation associated with the CO<NUM> refrigeration system (e.g., measurement devices, timing devices, pressure sensors, temperature sensors, etc.) and provide appropriate control signals to a variety of operable components of the CO<NUM> refrigeration system (e.g., compressors, valves, power supplies, flow diverters, etc.) to regulate the pressure, temperature, and/or flow at other locations within the CO<NUM> refrigeration system. Advantageously, the controller may be used to facilitate efficient operation of the CO<NUM> refrigeration system, reduce energy consumption, and improve system performance.

Before discussing further details of the CO<NUM> refrigeration system and/or the components thereof, it should be noted that references to "front," "back," "rear," "upward," "downward," "inner," "outer," "right," and "left" in this description are merely used to identify the various elements as they are oriented in the FIGURES. These terms are not meant to limit the element which they describe, as the various elements may be oriented differently in various applications.

It should further be noted that for purposes of this disclosure, the term "coupled" means the joining of two members directly or indirectly to one another. Such joining may be stationary in nature or moveable in nature and/or such joining may allow for the flow of fluids, transmission of forces, electrical signals, or other types of signals or communication between the two members. Such joining may be achieved with the two members or the two members and any additional intermediate members being integrally formed as a single unitary body with one another or with the two members or the two members and any additional intermediate members being attached to one another. Such joining may be permanent in nature or alternatively may be removable or releasable in nature.

Referring now to <FIG>, a CO<NUM> refrigeration system <NUM> is shown according to an exemplary embodiment. According to other embodiments, the refrigeration system may be configured to use other refrigerants, such as hydrofluorocarbons, ammonia, etc., and associate cooling device such as condensers, fluid coolers, etc. The illustrated CO<NUM> refrigeration system <NUM> may be a vapor compression refrigeration system which uses primarily carbon dioxide as a refrigerant. CO<NUM> refrigeration system <NUM> and is shown to include a system of pipes, conduits, or other fluid channels (e.g., fluid conduits <NUM>, <NUM>, <NUM>, <NUM>, and <NUM>) for transporting the carbon dioxide between various thermodynamic components of the refrigeration system. The thermodynamic components of CO<NUM> refrigeration system <NUM> are shown to include a gas cooler/condenser <NUM>, a high pressure valve <NUM>, a receiving tank <NUM>, a gas bypass valve <NUM>, a medium-temperature ("MT") system portion <NUM>, and a low-temperature ("LT") system portion <NUM>.

Gas cooler/condenser <NUM> may be a heat exchanger, fan-coil unit, or other similar device for removing heat from the CO<NUM> refrigerant. According to other embodiments that may use different refrigerants, the gas cooler/condenser may be a fluid cooler or condensing unit. Gas cooler/condenser <NUM> is shown receiving CO<NUM> vapor from fluid conduit <NUM>. In some embodiments, the CO<NUM> vapor in fluid conduit <NUM> may have a pressure within a range from approximately <NUM> bar to approximately <NUM> bar (i.e., about <NUM> psig to about <NUM> psig), depending on ambient temperature and other operating conditions. In some embodiments, gas cooler/condenser <NUM> may partially or fully condense CO<NUM> vapor into liquid CO<NUM> (e.g., if system operation is in a subcritical region). The condensation process may result in fully saturated CO<NUM> liquid or a liquid-vapor mixture (e.g., having a thermodynamic quality between <NUM> and <NUM>). In other embodiments, gas cooler/condenser <NUM> may cool the CO<NUM> vapor (e.g., by removing superheat) without condensing the CO<NUM> vapor into CO<NUM> liquid (e.g., if system operation is in a supercritical region). In some embodiments, the cooling/condensation process is an isobaric process. Gas cooler/condenser <NUM> is shown outputting the cooled and/or condensed CO<NUM> refrigerant into fluid conduit <NUM>. The gas cooler/condenser <NUM> may include the evaporative gas cooler described herein.

High pressure valve <NUM> receives the cooled and/or condensed CO<NUM> refrigerant from fluid conduit <NUM> and outputs the CO<NUM> refrigerant to fluid conduit <NUM>. High pressure valve <NUM> may control the pressure of the CO<NUM> refrigerant in gas cooler/condenser <NUM> by controlling an amount of CO<NUM> refrigerant permitted to pass through high pressure valve <NUM>. In some embodiments, high pressure valve <NUM> is a high pressure thermal expansion valve (e.g., if the pressure in fluid conduit <NUM> is greater than the pressure in fluid conduit <NUM>). In such embodiments, high pressure valve <NUM> may allow the CO<NUM> refrigerant to expand to a lower pressure state. The expansion process may be an isenthalpic and/or adiabatic expansion process, resulting in a flash evaporation of the high pressure CO<NUM> refrigerant to a lower pressure, lower temperature state. The expansion process may produce a liquid/vapor mixture (e.g., having a thermodynamic quality between <NUM> and <NUM>). In some embodiments, the CO<NUM> refrigerant expands to a pressure of approximately <NUM> bar (e.g., about <NUM> psig), which corresponds to a temperature of approximately <NUM>° F. The CO<NUM> refrigerant then flows from fluid conduit <NUM> into receiving tank <NUM>.

Receiving tank <NUM> (e.g., receiver, receiver tank, etc.) collects the CO<NUM> refrigerant from fluid conduit <NUM>. In some embodiments, receiving tank <NUM> may be a flash tank or other fluid reservoir. Receiving tank <NUM> includes a CO<NUM> liquid portion and a CO<NUM> vapor portion and may contain a partially saturated mixture of CO<NUM> liquid and CO<NUM> vapor. In some embodiments, receiving tank <NUM> separates the CO<NUM> liquid from the CO<NUM> vapor. The CO<NUM> liquid may exit receiving tank <NUM> through fluid conduits <NUM>. Fluid conduits <NUM> may be liquid headers leading to either MT system portion <NUM> or LT system portion <NUM>. The CO<NUM> vapor may exit receiving tank <NUM> through fluid conduit <NUM>. Fluid conduit <NUM> is shown leading the CO<NUM> vapor to gas bypass valve <NUM>.

Gas bypass valve <NUM> is shown receiving the CO<NUM> vapor from fluid conduit <NUM> and outputting the CO<NUM> refrigerant to MT system portion <NUM>. In some embodiments, gas bypass valve <NUM> may be operated to regulate or control the pressure within receiving tank <NUM> (e.g., by adjusting an amount of CO<NUM> refrigerant permitted to pass through gas bypass valve <NUM>). For example, gas bypass valve <NUM> may be adjusted (e.g., variably opened or closed) to adjust the mass flow rate, volume flow rate, or other flow rates of the CO<NUM> refrigerant through gas bypass valve <NUM>. Gas bypass valve <NUM> may be opened and closed (e.g., manually, automatically, by a controller, etc.) as needed to regulate the pressure within receiving tank <NUM>.

In some embodiments, gas bypass valve <NUM> includes a sensor for measuring a flow rate (e.g., mass flow, volume flow, etc.) of the CO<NUM> refrigerant through gas bypass valve <NUM>. In other embodiments, gas bypass valve <NUM> includes an indicator (e.g., a gauge, a dial, etc.) from which the position of gas bypass valve <NUM> may be determined. This position may be used to determine the flow rate of CO<NUM> refrigerant through gas bypass valve <NUM>, as such quantities may be proportional or otherwise related.

In some embodiments, gas bypass valve <NUM> may be a thermal expansion valve (e.g., if the pressure on the downstream side of gas bypass valve <NUM> is lower than the pressure in fluid conduit <NUM>). According to one embodiment, the pressure within receiving tank <NUM> is regulated by gas bypass valve <NUM> to a pressure of approximately <NUM> bar, which corresponds to about <NUM>°F. Advantageously, this pressure/temperature state (i.e., approximately <NUM> bar, approximately <NUM>°F ) may facilitate the use of copper tubing/piping for the downstream CO<NUM> lines of the system. Additionally, this pressure/temperature state may allow such copper tubing to operate in a substantially frost-free manner.

Still referring to <FIG>, MT system portion <NUM> is shown to include one or more expansion valves <NUM>, one or more MT evaporators <NUM>, and one or more MT compressors <NUM>. In various embodiments, any number of expansion valves <NUM>, MT evaporators <NUM>, and MT compressors <NUM> may be present. Expansion valves <NUM> may be electronic expansion valves or other similar expansion valves. Expansion valves <NUM> are shown receiving liquid CO<NUM> refrigerant from fluid conduit <NUM> and outputting the CO<NUM> refrigerant to MT evaporators <NUM>. Expansion valves <NUM> may cause the CO<NUM> refrigerant to undergo a rapid drop in pressure, thereby expanding the CO<NUM> refrigerant to a lower pressure, lower temperature state. In some embodiments, expansion valves <NUM> may expand the CO<NUM> refrigerant to a pressure of approximately <NUM> bar. The expansion process may be an isenthalpic and/or adiabatic expansion process.

MT evaporators <NUM> are shown receiving the cooled and expanded CO<NUM> refrigerant from expansion valves <NUM>. In some embodiments, MT evaporators may be associated with display cases/devices (e.g., if CO<NUM> refrigeration system <NUM> is implemented in a supermarket setting). MT evaporators <NUM> may be configured to facilitate the transfer of heat from the display cases/devices into the CO<NUM> refrigerant. The added heat may cause the CO<NUM> refrigerant to evaporate partially or completely. According to one embodiment, the CO<NUM> refrigerant is fully evaporated in MT evaporators <NUM>. In some embodiments, the evaporation process may be an isobaric process. MT evaporators <NUM> are shown outputting the CO<NUM> refrigerant via fluid conduits <NUM>, leading to MT compressors <NUM>.

MT compressors <NUM> compress the CO<NUM> refrigerant into a superheated vapor having a pressure within a range of approximately <NUM> bar to approximately <NUM> bar. The output pressure from MT compressors <NUM> may vary depending on ambient temperature and other operating conditions. In some embodiments, MT compressors <NUM> operate in a transcritical mode. In operation, the CO<NUM> discharge gas exits MT compressors <NUM> and flows through fluid conduit <NUM> into gas cooler/condenser <NUM>.

Still referring to <FIG>, LT system portion <NUM> is shown to include one or more expansion valves <NUM>, one or more LT evaporators <NUM>, and one or more LT compressors <NUM>.

In various embodiments, any number of expansion valves <NUM>, LT evaporators <NUM>, and LT compressors <NUM> may be present. In some embodiments, LT system portion <NUM> may be omitted and the CO<NUM> refrigeration system <NUM> may operate with an air conditioning (AC) module interfacing with only MT system <NUM>.

Expansion valves <NUM> may be electronic expansion valves or other similar expansion valves. Expansion valves <NUM> are shown receiving liquid CO<NUM> refrigerant from fluid conduit <NUM> and outputting the CO<NUM> refrigerant to LT evaporators <NUM>. Expansion valves <NUM> may cause the CO<NUM> refrigerant to undergo a rapid drop in pressure, thereby expanding the CO<NUM> refrigerant to a lower pressure, lower temperature state. The expansion process may be an isenthalpic and/or adiabatic expansion process. In some embodiments, expansion valves <NUM> may expand the CO<NUM> refrigerant to a lower pressure than expansion valves <NUM>, thereby resulting in a lower temperature CO<NUM> refrigerant. Accordingly, LT system portion <NUM> may be used in conjunction with a freezer system or other lower temperature display cases.

LT evaporators <NUM> are shown receiving the cooled and expanded CO<NUM> refrigerant from expansion valves <NUM>. In some embodiments, LT evaporators may be associated with display cases/devices (e.g., if CO<NUM> refrigeration system <NUM> is implemented in a supermarket setting). LT evaporators <NUM> may be configured to facilitate the transfer of heat from the display cases/devices into the CO<NUM> refrigerant. The added heat may cause the CO<NUM> refrigerant to evaporate partially or completely. In some embodiments, the evaporation process may be an isobaric process. LT evaporators <NUM> are shown outputting the CO<NUM> refrigerant via fluid conduit <NUM>, leading to LT compressors <NUM>.

LT compressors <NUM> compress the CO<NUM> refrigerant. In some embodiments, LT compressors <NUM> may compress the CO<NUM> refrigerant to a pressure of approximately <NUM> bar (e.g., about <NUM> psig) having a saturation temperature of approximately <NUM>° F (e.g., about - <NUM>). LT compressors <NUM> are shown outputting the CO<NUM> refrigerant through fluid conduit <NUM>. Fluid conduit <NUM> may be fluidly connected with the suction (e.g., upstream) side of MT compressors <NUM>.

In some embodiments, the CO<NUM> vapor that is bypassed through gas bypass valve <NUM> is mixed with the CO<NUM> refrigerant gas exiting MT evaporators <NUM> (e.g., via fluid conduit <NUM>). The bypassed CO<NUM> vapor may also mix with the discharge CO<NUM> refrigerant gas exiting LT compressors <NUM> (e.g., via fluid conduit <NUM>). The combined CO<NUM> refrigerant gas may be provided to the suction side of MT compressors <NUM>.

Referring now to <FIG>, a refrigerant cooling device shown as a gas cooler <NUM> (e.g., adiabatic gas cooler, evaporative gas cooler, adiabatic gas condenser, evaporative gas condenser, gas condenser, etc.) is shown according to an exemplary embodiment. The gas cooler <NUM> can include the gas cooler/condenser <NUM> described above. The gas cooler <NUM> may include one or more heat exchanger coils <NUM>. For example, the heat exchanger coil <NUM> can include a coil, microchannel coil, condenser coil, tube coil, cooling coil, or fin coil. The heat exchanger coil <NUM> can include multiple tubes through which refrigerant flows. The heat exchanger coil <NUM> can receive ambient cool air drawn over the heat exchanger coil <NUM> by a fan. According to one embodiment, the gas cooler <NUM> may include a plurality of heat exchanger coils <NUM>. The heat exchanger coil <NUM> may be arranged in a "V" shape.

To enhance the cooling efficiency of heat exchanger coils <NUM>, the gas cooler <NUM> may include one or more moisture panels such as a first moisture panel <NUM> and a second moisture panel <NUM>. The first moisture panel <NUM> (e.g., first adiabatic panel, first adiabatic pad, first adiabatic moisture pad, first moisture pad, first cooling pad, etc.) can be disposed external to the heat exchanger coils <NUM>. The first moisture panel <NUM> may be used to generate pre-cooled air by an evaporative cooling process. For example, ambient air may pass through the first moisture panel <NUM> before the ambient air passes through the heat exchanger coils <NUM>. As the ambient air passes through the first moisture panel <NUM>, the ambient air cools as the moisture in the first moisture panel <NUM> evaporates and becomes pre-cooled air. The gas cooler <NUM> may include one or more moisture pads adjacent to the one or more cooling coils. For example, a plurality of moisture pads can be disposed adjacent to a plurality of cooling coils. According to the illustrated embodiment of <FIG>, the first moisture panel <NUM> is disposed outwardly and co-extensively with each heat exchanger coil <NUM>. The first moisture panel <NUM> can provide an evaporative cooling effect when air is drawn through the first moisture panel <NUM>. The first moisture panel <NUM> can increase the cooling efficiency of the heat exchanger coils <NUM>.

In addition, the gas cooler <NUM> may include a second moisture panel <NUM> (e.g., second adiabatic panel, second adiabatic pad, second adiabatic moisture pad, second moisture pad, second cooling pad, etc.) disposed external to the heat exchanger coils <NUM>. The second moisture panel <NUM> may be used to generate pre-cooled air by an evaporative cooling process. For example, ambient air may pass through the second moisture panel <NUM> before the ambient air passes through the heat exchanger coils <NUM>. As the ambient air passes through the second moisture panel <NUM>, the ambient air cools as the moisture in the second moisture panel <NUM> evaporates and becomes pre-cooled air. According to the illustrated embodiment of <FIG>, the second moisture panel <NUM> is disposed outwardly and co-extensively with each heat exchanger coil <NUM>. The second moisture panel <NUM> can provide an evaporative cooling effect when air is drawn through the second moisture panel <NUM>. The second moisture panel <NUM> can increase the cooling efficiency of the heat exchanger coils <NUM>.

The second moisture panel <NUM> can be separated from the first moisture panel <NUM> by a distance <NUM>. For example, the first moisture panel <NUM> can be separated from the second moisture panel <NUM> by a distance <NUM> at a base of the first moisture panel <NUM> and a base of the second moisture panel <NUM>. The first moisture panel <NUM> can be separated from the second moisture panel <NUM> by a distance <NUM> at a center of the first moisture panel <NUM> and a center of the second moisture panel <NUM>. The first moisture panel <NUM> can be separated from the second moisture panel <NUM> by a distance <NUM> at a top of the first moisture panel <NUM> and a top of the second moisture panel <NUM>.

The gas cooler <NUM> may also include one or more fans <NUM>. The fans <NUM> draw ambient air or pre-cooled air through the heat exchanger coils <NUM>, thereby cooling and condensing the refrigerant and providing cooling to the CO<NUM> refrigeration system <NUM>. The gas cooler <NUM> may include one or more motors that power the fans <NUM>. The fans <NUM> draw air through moisture panels and subsequently through the heat exchanger coils <NUM>. The fans <NUM> are shown located above the heat exchanger coils <NUM>. The first moisture panel <NUM> can provide an evaporative cooling effect to the heat exchanger coil <NUM> when air is drawn through the first moisture panel <NUM> by the fans <NUM>. The second moisture panel <NUM> can provide an evaporative cooling effect to the heat exchanger coil <NUM> when air is drawn through the second moisture panel <NUM> by the fans <NUM>.

Referring now to <FIG>, a cross-section <NUM> of a gas cooler <NUM> is shown according to an exemplary embodiment. The gas cooler <NUM> can include a first nozzle array <NUM> (e.g., first water spray nozzle array, one or more spray nozzles, etc.). The first nozzle array <NUM> can be disposed external to the first moisture panel <NUM>. For example, the first nozzle array <NUM> can be located on the exterior of the first moisture panel <NUM>. The first nozzle array <NUM> can be configured to provide an atomized spray of electrostatically charged water droplets to the first moisture panel <NUM>. The atomized spray of electrostatically charged water droplets and the first moisture panel <NUM> are oppositely charged. For example, the first nozzle array <NUM> can include nozzles, each of which can include a barrel. An electrical charge can be applied to the barrel of each of the nozzles, which applies a charge to the fluid (e.g., water) and/or water droplets. As the fluid is propelled through the nozzle, the water gains an electric charge. For example, the barrel of the nozzle can transfer a negative charge to the droplets (e.g., water droplets, etc.). The first moisture panel <NUM> can be positively charged (or grounded) to create an attractive force to the droplets. The positively charged first moisture panel <NUM> can create an attraction to the negatively charged droplets. Alternatively, the barrel of the nozzle can transfer a positive charge to the droplets (e.g., water droplets, etc.) and the first moisture panel <NUM> can be negatively charged (or grounded). The negatively charged first moisture panel <NUM> can create an attraction to the positively charged droplets. Electrostatically spraying droplets onto the first moisture panel <NUM> can allow more water to land on the charged first moisture panel <NUM>. Electrostatically spraying droplets onto the first moisture panel <NUM> can allow more water to be retained by the first moisture panel <NUM>. Due to the charge, when the water leaves the nozzle, the water is attracted to the first moisture panel <NUM> and "sticks" (e.g., wets, adheres, etc.) to the first moisture panel <NUM>. The attraction improves coverage of wetting on the moisture panels and minimizes dry spots. The attraction also improves the water efficiency by more effectively covering the surface which results in less water usage. The attraction further reduces "blow-through" of moisture through the moisture panels. For example, the electrostatic attraction of the atomized spray of electrostatically charged droplets and the moisture panels substantially prevents blow-through of droplets beyond an inside surface of the moisture panel.

The gas cooler <NUM> can include a second nozzle array <NUM> (e.g., second water spray nozzle array, one or more spray nozzles, etc.). The second nozzle array <NUM> can be disposed external to the second moisture panel <NUM>. For example, the second nozzle array <NUM> can be located on the exterior of the second moisture panel <NUM>. The second nozzle array <NUM> can be configured to provide an atomized spray of electrostatically charged water droplets to the second moisture panel <NUM>. The atomized spray of electrostatically charged water droplets and the second moisture panel <NUM> are oppositely charged. For example, the second nozzle array <NUM> can include nozzles, each of which can include a barrel. An electrical charge can be applied to the barrel of each of the nozzles, which applies a charge to the fluid (e.g., water) and/or water droplets. As the fluid is propelled through the nozzle, the water gains an electric charge. For example, the barrel of the nozzle can transfer a negative charge to the droplets (e.g., water droplets, etc.). The second moisture panel <NUM> can be positively charged (or grounded) to create an attractive force to the droplets. The positively charged second moisture panel <NUM> can create an attraction to the negatively charged droplets. Alternatively, the barrel of the nozzle can transfer a positive charge to the droplets (e.g., water droplets, etc.) and the second moisture panel <NUM> can be negatively charged (or grounded). The negatively charged second moisture panel <NUM> can create an attraction to the positively charged droplets. Electrostatically spraying droplets onto the second moisture panel <NUM> can allow more water to land on the charged second moisture panel <NUM>. Electrostatically spraying droplets onto the first moisture panel <NUM> can allow more water to be retained by the second moisture panel <NUM>. Due to the charge, when the water leaves the nozzle, the water is attracted to the second moisture panel <NUM> and "sticks" (e.g., wets, adheres, etc.) to the second moisture panel <NUM>. In some embodiments, the first nozzle array <NUM> and the second nozzle array <NUM> form a single nozzle array.

The gas cooler <NUM> can also include a moisture sensor <NUM>. The moisture sensor <NUM> can be configured to provide a signal representative of a moisture level from at least one of the first moisture panel <NUM> and/or the second moisture panel <NUM>. For example, the moisture sensor <NUM> can be configured to provide a signal representative of a moisture level from the first moisture panel <NUM>. The moisture sensor <NUM> can also be configured to provide a signal representative of a moisture level from the second moisture panel <NUM>.

In some embodiments, the moisture level is a first moisture level and the moisture sensor is a first moisture sensor. The first moisture sensor can be configured to provide the signal representative of the first moisture level from the first moisture panel <NUM>. In some embodiments, the gas cooler <NUM> can include a second moisture sensor. The second moisture sensor can be configured to provide a signal representative of a second moisture level from the second moisture panel <NUM>. The first moisture sensor can be configured to provide the signal representative of the first moisture level from a first moisture pad of the one or more moisture pads. The second moisture sensor can be configured to provide a signal representative of a second moisture level from a second moisture pad of the one or more moisture pads.

In some embodiments, the moisture sensor <NUM> can be configured to provide the signal representative of the moisture level from at least one of a bottom of the first moisture panel or a bottom of the second moisture panel. For example, the moisture sensor <NUM> can be configured to provide the signal representative of the moisture level from the bottom of the first moisture panel <NUM>. The moisture sensor <NUM> can be configured to provide the signal representative of the moisture level from the bottom of the second moisture panel <NUM>. The moisture sensor <NUM> can be configured to provide the signal representative of the moisture level from a bottom of the one or more moisture pads. In some embodiments, the moisture sensor is configured to provide the signal representative of the moisture level from a drainage receptacle disposed beneath the first moisture panel and the second moisture panel.

The gas cooler <NUM> can also include a controller <NUM>. The controller <NUM> can be communicatively coupled to the moisture sensor <NUM>. The controller <NUM> can be configured to receive the signal representative of the moisture level from at least one of the first moisture panel <NUM> or the second moisture panel <NUM>. For example, the controller <NUM> can be configured to receive the signal representative of the moisture level from the first moisture panel <NUM> and the moisture level from the second moisture panel <NUM>.

In some embodiments, the controller <NUM> can receive a signal representative of the first moisture level and compare the signal to a benchmark value. For example, the benchmark value can represent an adequately wetted (e.g., not over-wetted and not under-wetted) first moisture panel <NUM>. The controller <NUM> can determine that the first moisture level is greater than, less than, or equal to the benchmark value. The controller <NUM> can be configured to receive the signal representative of the first moisture level from the first moisture pad. The controller <NUM> can receive a signal representative of the first moisture level and determine if the signal is within a range (e.g., <NUM>%, <NUM>%, <NUM>%, etc.) of a target moisture level.

In some embodiments, the controller <NUM> can receive a signal representative of the second moisture level and compare the signal to a benchmark value. For example, the benchmark value can represent an adequately wetted (e.g., not over-wetted and not under-wetted) second moisture panel <NUM>. The controller <NUM> can determine that the second moisture level is greater than, less than, or equal to the benchmark value. The controller <NUM> can be configured to receive the signal representative of the second moisture level from the second moisture pad. The controller <NUM> can receive a signal representative of the second moisture level and determine if the signal is within a range (e.g., <NUM>%, <NUM>%, <NUM>%, etc.) of a target moisture level.

The controller <NUM> can be configured to control a supply of water to at least one of the first moisture panel <NUM> or the second moisture panel <NUM> (e.g., individually or in combination) in response to the signal representative of the moisture level. For example, the controller <NUM> can be configured to collectively control a supply of water to the first moisture panel <NUM> in response to the signal representative of the moisture level and control a supply of water to the second moisture panel <NUM> in response to the signal representative of the moisture level. For example, the controller <NUM> can decrease the supply of water to the one or more moisture pads in response to a signal that the moisture level is higher than a benchmark level. The controller <NUM> can decrease the supply of water to the one or more moisture pads in response to a signal that indicates the moisture level in the moisture pads exceeds the benchmark level. The controller <NUM> can increase the supply of water to the one or more moisture pads in response to a signal that the moisture level is lower than the benchmark level. The controller <NUM> can retain (e.g., maintain, hold constant, etc.) the supply of water to the moisture pads in response to a signal that the moisture pads is adequately wetted (e.g., not over-wetted and not under-wetted).

Individually, the controller <NUM> can be configured to control the supply of water to the first moisture panel <NUM> in response to the signal representative of the first moisture level. For example, the controller <NUM> can be configured to increase the supply of water to the first moisture panel <NUM> in response to the first moisture level being less than the benchmark value. The controller <NUM> can be configured to decrease the supply of water to the first moisture panel <NUM> in response to the first moisture level being greater than the benchmark value. The controller <NUM> can be configured to maintain the supply of water to the first moisture panel <NUM> in response to the first moisture level being equal to the benchmark value. The controller <NUM> can be configured to control the supply of water to the first moisture pad in response to the signal representative of the first moisture level. The controller <NUM> can be configured to control the supply of water to the first moisture pad in response to the signal representative of both the first moisture level and the second moisture level.

Also, the controller <NUM> can be configured to individually control the supply of water to the second moisture panel <NUM> in response to the signal representative of the second moisture level. For example, the controller <NUM> can be configured to increase the supply of water to the second moisture panel <NUM> in response to the second moisture level being less than the benchmark value. The controller <NUM> can be configured to decrease the supply of water to the second moisture panel <NUM> in response to the second moisture level being greater than the benchmark value. The controller <NUM> can be configured to maintain the supply of water to the second moisture panel <NUM> in response to the second moisture level being equal to the benchmark value. The controller <NUM> can be configured to control the supply of water to the second moisture pad in response to the signal representative of the second moisture level. The controller <NUM> can be configured to control the supply of water to the second moisture pad in response to the signal representative of both the first moisture level and the second moisture level.

The controller <NUM> can be configured to control the supply of water using a variable rate controller <NUM> (e.g., flow control valve, etc.). For example, the variable rate controller <NUM> can adjust the application rate of droplets to an optimal amount for each moisture panel or for a single moisture panel. For example, the variable rate controller <NUM> can provide a higher application rate of droplets to the first moisture panel <NUM> than to the second moisture panel <NUM>. The variable rate controller <NUM> can provide a higher application rate of droplets to the first moisture panel <NUM> than to the second moisture panel <NUM> in response to a signal representative of the moisture level corresponding to the first moisture panel <NUM> being lower than a signal representative of the moisture level corresponding to the second moisture panel <NUM>. The variable rate controller <NUM> can provide a higher application rate of droplets to a first portion of the first moisture panel <NUM> than to a second portion of the first moisture panel <NUM>. The variable rate controller <NUM> can provide a higher application rate of droplets to a first portion of the first moisture panel <NUM> than to a second portion of the first moisture panel <NUM> in response to a signal representative of the moisture level corresponding to the first portion of the first moisture panel <NUM> being lower than a signal representative of the moisture level corresponding to the second portion of the first moisture panel <NUM>.

In some embodiments, the controller <NUM> can be configured to supply a voltage to the nozzles of the first nozzle array <NUM> and the second nozzle array <NUM>. The controller <NUM> can select the voltage so as to cause the first nozzle array <NUM> and the second nozzle array <NUM> to provide a target amount of electrostatically charged droplets. The controller <NUM> can select the voltage so as to cause the one or more spray nozzles to provide a target amount of electrostatically charged droplets. For example, the target amount of electrostatically charged droplets can include an amount of electrostatically charged droplets that does not cause excess water to leave the first moisture panel <NUM> and the second moisture panel <NUM>.

In some embodiments, the controller <NUM> can be incorporated into a system level control device (such as a condensing unit rack controller) that is configured to operate the any or all other components of the system such as the evaporator, the compressor, the gas cooler, the receiver, and the expansion valve. For example, the controller <NUM> can be configured to operate the MT evaporators <NUM>. The controller <NUM> can be configured to operate the LT evaporators <NUM>. The controller <NUM> can be configured to operate the MT compressors <NUM>. The controller <NUM> can be configured to operate the LT compressors <NUM>. The controller <NUM> can be configured to operate the gas cooler/condenser <NUM>. The controller <NUM> can be configured to operate the gas cooler <NUM>. The controller <NUM> can be configured to operate the receiving tank <NUM>. The controller <NUM> can be configured to operate the expansion valves <NUM>.

Referring now to <FIG>, a schematic <NUM> of an atomized spray of electrostatically charged droplets is shown according to an exemplary embodiment. The first nozzle array <NUM> and the second nozzle array <NUM> each include a plurality of nozzles <NUM>. The nozzles can include a liquid stream <NUM> (e.g., liquid line, etc.). The liquid stream <NUM> can include a stream of liquid (e.g., water, etc.). The nozzle <NUM> can also include an air stream <NUM> (e.g., air line, etc.). The air stream <NUM> can include a stream of air. The air stream <NUM> can be a laminar air stream when the air is inside the nozzle <NUM>, and can be a turbulent air stream when the air exits the nozzle <NUM>.

The liquid stream <NUM> and the air stream <NUM> can meet at a tip of the nozzle. For example, the low pressure and high volume air flow can atomize the liquid into droplets <NUM>. The droplets <NUM> can be uniform in size. The droplets <NUM> can pass through an electric field. For example, an electrode <NUM> of the nozzle <NUM> can apply a charge (e.g., positive charge, negative charge, etc.) to the droplets <NUM>. The droplets <NUM> can be carried towards a spray target <NUM> (e.g., first moisture panel <NUM>, second moisture panel <NUM>, etc.). The spray target <NUM> may have an opposite charge than that of the droplets <NUM>. For example, the spray target <NUM> can have a positive charge and the droplets <NUM> can have a negative charge. Alternatively, the spray target <NUM> can have a negative charge and the droplets <NUM> can have a positive charge. The charged droplets <NUM> are attracted to the oppositely charged spray target <NUM>.

<FIG> is a block diagram of an example method <NUM> of providing an evaporative gas cooler for a CO2 refrigeration system. In a similar manner, according to other embodiments, an adiabatic, evaporative cooler may be provided as a condenser or fluid cooler, etc. in a refrigeration system using other refrigerants, such as a hydrofluorocarbon or ammonia, etc. In brief summary, the method <NUM> can include providing heat exchanger coils <NUM>. The method <NUM> can include installing moisture panels <NUM>. The method <NUM> can also include installing nozzle arrays <NUM>. The method <NUM> further includes configuring a moisture sensor <NUM>, and providing a controller <NUM>. The method <NUM> can also include receiving moisture level signals <NUM>, and controlling a supply of water <NUM>.

The method <NUM> can also include providing heat exchanger coils <NUM>. The heat exchanger coil may include a microchannel coil, condenser coil, tube coil, cooling coil, or fin coil.

The method <NUM> further includes installing moisture panels <NUM>, such as a first moisture panel external to the heat exchanger coil and a second moisture panel external to and near the heat exchanger coils.

The method <NUM> also includes installing nozzle arrays <NUM>, such as a first nozzle array external to the first moisture panel and a second nozzle array external to the second moisture panel. The nozzle arrays provide an atomized spray of electrostatically charged droplets to the moisture panels.

The method <NUM> also includes installing a moisture sensor <NUM> to provide a signal representative of a moisture level from the first moisture panel and/or the second moisture panel (individually or in combination).

The method <NUM> also includes providing a controller <NUM> communicatively coupled to the moisture sensor. In some embodiments, the method <NUM> can include supplying, by the controller, a voltage to the first nozzle array and the second nozzle array. The method <NUM> can include selecting, by the controller, the voltage so as to cause the first nozzle array and the second nozzle array to provide a target amount of electrostatically charged droplets.

The method <NUM> can include receiving moisture level signals <NUM>. Receiving moisture level signals can include receiving, by the controller, the signal representative of the moisture level from the first moisture panel and/or the second moisture panel.

The method <NUM> can include controlling a supply of water <NUM>. Controlling a supply of water can include controlling, by the controller, a supply of water to one or both of the first moisture panel or the second moisture panel in response to the signal representative of the moisture level.

<FIG> is a block diagram of an example method <NUM> of operating an adiabatic gas cooler. The method <NUM> can begin with receiving a signal by the controller <NUM>. The signal can be representative of a moisture level from one or more moisture panels, such as a signal representative of a first moisture level from a first moisture panel and/or a signal representative of a second moisture level from a second moisture panel. The signal can also be representative of a moisture level from both a first moisture panel and a second moisture panel.

The method <NUM> continues with determining, by the controller <NUM>, if the moisture level is within a range (e.g., <NUM>%, <NUM>%, <NUM>%, etc.) of a target moisture level <NUM>. If the controller <NUM> determines that the moisture level is within the range of the target moisture level, the method <NUM> restarts (e.g., ends and continues to block <NUM> again, etc.).

If the controller <NUM> determines that the moisture level is not within the range of the target moisture level, the method <NUM> continues in block <NUM> with determining, by the controller <NUM>, if the moisture level is greater than the maximum value of the target range. If the controller <NUM> determines that the moisture level is greater than the maximum value of the target range, the method <NUM> continues in block <NUM> with decreasing, by the controller, the supply of water provided to the moisture panels. For example, the moisture level being greater than the maximum value of the target range may indicate that the moisture panels are receiving excess moisture. The method <NUM> then restarts (e.g., ends and continues to block <NUM> again, etc.).

If the controller <NUM> determines that the moisture level is not greater than the maximum value of the target range, the method <NUM> continues in block <NUM> with increasing, by the controller, the supply of water provided to the moisture panels. For example, the moisture level being less than the minimum value of the target range may indicate that the moisture panels are not receiving enough moisture. The method <NUM> then restarts (e.g., ends and continues to block <NUM> again, etc.).

The construction and arrangement of the elements of the CO<NUM> refrigeration system with an adiabatic electrostatic gas cooler as shown in the exemplary embodiments are illustrative only. Although only a few embodiments have been described in detail in this disclosure, many modifications are possible (e.g., variations in sizes, dimensions, structures, shapes and proportions of the various elements, values of parameters, mounting arrangements, use of materials, colors, orientations, etc.). For example, the position of elements may be reversed or otherwise varied and the nature or number of discrete elements or positions may be altered or varied. Accordingly, all such modifications are intended to be included within the scope of the present disclosure. The order or sequence of any process or method steps may be varied or re-sequenced according to alternative embodiments. Other substitutions, modifications, changes, and omissions may be made in the design, operating conditions and arrangement of the exemplary embodiments without departing from the scope of the present disclosure.

The present disclosure contemplates methods, systems and program products on any machine-readable media for accomplishing various operations. The embodiments of the present disclosure may be implemented using existing computer processors, or by a special purpose computer processor for an appropriate system, incorporated for this or another purpose, or by a hardwired system. Embodiments within the scope of the present disclosure include program products comprising machine-readable media for carrying or having machine-executable instructions or data structures stored thereon. Such machine-readable media can be any available media that can be accessed by a general purpose or special purpose computer or other machine with a processor. By way of example, such machine-readable media can comprise RAM, ROM, EPROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium which can be used to carry or store desired program code in the form of machine-executable instructions or data structures and which can be accessed by a general purpose or special purpose computer or other machine with a processor. When information is transferred or provided over a network or another communications connection (either hardwired, wireless, or a combination of hardwired or wireless) to a machine, the machine properly views the connection as a machine-readable medium. Thus, any such connection is properly termed a machine-readable medium. Combinations of the above are also included within the scope of machine-readable media. Machine-executable instructions include, for example, instructions and data which cause a general purpose computer, special purpose computer, or special purpose processing machines to perform a certain function or group of functions.

Although the figures show a specific order of method steps, the order of the steps may differ from what is depicted. Also two or more steps may be performed concurrently or with partial concurrence. Such variation will depend on the software and hardware systems chosen and on designer choice. All such variations are within the scope of the disclosure. Likewise, software implementations could be accomplished with standard programming techniques with rule based logic and other logic to accomplish the various connection steps, processing steps, comparison steps and decision steps.

Any references to implementations or elements or acts of the systems and methods herein referred to in the singular can include implementations including a plurality of these elements, and any references in plural to any implementation or element or act herein can include implementations including only a single element.

Any implementation disclosed herein may be combined with any other implementation, and references to "an implementation," "some implementations," "an alternate implementation," "various implementations," "one implementation" or the like are not necessarily mutually exclusive and are intended to indicate that a particular feature, structure, or characteristic described in connection with the implementation may be included in at least one implementation. Such terms as used herein are not necessarily all referring to the same implementation. Any implementation may be combined with any other implementation, inclusively or exclusively, in any manner consistent with the aspects and implementations disclosed herein.

References to "or" may be construed as inclusive so that any terms described using "or" may indicate any of a single, more than one, and all of the described terms. References to at least one of a conjunctive list of terms may be construed as an inclusive OR to indicate any of a single, more than one, and all of the described terms. For example, a reference to "at least one of 'A' and 'B'" can include only 'A', only 'B', as well as both 'A' and 'B'. Elements other than 'A' and 'B' can also be included.

The systems and methods described herein may be embodied in other specific forms without departing from the characteristics thereof. The foregoing implementations are illustrative rather than limiting of the described systems and methods.

Claim 1:
A cooling device for a refrigeration system, comprising:
one or more heat exchanger coils (<NUM>);
a first moisture panel (<NUM>) disposed external to the one or more heat exchanger coils (<NUM>);
a second moisture panel (<NUM>) disposed external to the one or more heat exchanger coils (<NUM>), the second moisture panel (<NUM>) separated from the first moisture panel (<NUM>) by a distance (<NUM>);
a first nozzle array (<NUM>) disposed external to the first moisture panel (<NUM>) and configured to provide an atomized spray of electrostatically charged droplets to the first moisture panel (<NUM>);
a second nozzle array (<NUM>) disposed external to the second moisture panel (<NUM>) and configured to provide an atomized spray of electrostatically charged droplets to the second moisture panel (<NUM>);
a moisture sensor (<NUM>) configured to provide a signal representative of a moisture level from at least one of the first moisture panel (<NUM>) or the second moisture panel (<NUM>); and
a controller (<NUM>) communicatively coupled to the moisture sensor (<NUM>), the controller (<NUM>) configured to:
receive the signal representative of the moisture level from at least one of the first moisture panel (<NUM>) or the second moisture panel (<NUM>); and
control a supply of water to at least one of the first moisture panel (<NUM>) or the second moisture panel (<NUM>) in response to the signal representative of the moisture level.